graphql-engine/server/src-lib/Hasura/RemoteSchema/SchemaCache/Build.hs

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scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
{-# LANGUAGE Arrows #-}
module Hasura.RemoteSchema.SchemaCache.Build
( buildRemoteSchemas,
addRemoteSchemaP2Setup,
)
where
import Control.Arrow.Extended
import Control.Arrow.Interpret
import Control.Monad.Trans.Control (MonadBaseControl)
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
import Data.Aeson
import Data.ByteString.Lazy qualified as BL
import Data.Environment qualified as Env
import Data.HashMap.Strict.Extended qualified as M
import Data.Text.Extended
import Hasura.Base.Error
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
import Hasura.GraphQL.RemoteServer
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
import Hasura.Incremental qualified as Inc
import Hasura.Prelude
import Hasura.RQL.DDL.Schema.Cache.Common
import Hasura.RQL.DDL.Schema.Cache.Permission
import Hasura.RQL.Types.Metadata.Object
import Hasura.RQL.Types.Roles
import Hasura.RQL.Types.Roles.Internal (CheckPermission (..))
import Hasura.RQL.Types.SchemaCache
import Hasura.RQL.Types.SchemaCache.Build
import Hasura.RemoteSchema.Metadata
import Hasura.RemoteSchema.SchemaCache.Permission (resolveRoleBasedRemoteSchema)
import Hasura.RemoteSchema.SchemaCache.Types
harmonize network manager handling ## Description ### I want to speak to the `Manager` Oh boy. This PR is both fairly straightforward and overreaching, so let's break it down. For most network access, we need a [`HTTP.Manager`](https://hackage.haskell.org/package/http-client-0.1.0.0/docs/Network-HTTP-Client-Manager.html). It is created only once, at the top level, when starting the engine, and is then threaded through the application to wherever we need to make a network call. As of main, the way we do this is not standardized: most of the GraphQL execution code passes it "manually" as a function argument throughout the code. We also have a custom monad constraint, `HasHttpManagerM`, that describes a monad's ability to provide a manager. And, finally, several parts of the code store the manager in some kind of argument structure, such as `RunT`'s `RunCtx`. This PR's first goal is to harmonize all of this: we always create the manager at the root, and we already have it when we do our very first `runReaderT`. Wouldn't it make sense for the rest of the code to not manually pass it anywhere, to not store it anywhere, but to always rely on the current monad providing it? This is, in short, what this PR does: it implements a constraint on the base monads, so that they provide the manager, and removes most explicit passing from the code. ### First come, first served One way this PR goes a tiny bit further than "just" doing the aforementioned harmonization is that it starts the process of implementing the "Services oriented architecture" roughly outlined in this [draft document](https://docs.google.com/document/d/1FAigqrST0juU1WcT4HIxJxe1iEBwTuBZodTaeUvsKqQ/edit?usp=sharing). Instead of using the existing `HasHTTPManagerM`, this PR revamps it into the `ProvidesNetwork` service. The idea is, again, that we should make all "external" dependencies of the engine, all things that the core of the engine doesn't care about, a "service". This allows us to define clear APIs for features, to choose different implementations based on which version of the engine we're running, harmonizes our many scattered monadic constraints... Which is why this service is called "Network": we can refine it, moving forward, to be the constraint that defines how all network communication is to operate, instead of relying on disparate classes constraint or hardcoded decisions. A comment in the code clarifies this intent. ### Side-effects? In my Haskell? This PR also unavoidably touches some other aspects of the codebase. One such example: it introduces `Hasura.App.AppContext`, named after `HasuraPro.Context.AppContext`: a name for the reader structure at the base level. It also transforms `Handler` from a type alias to a newtype, as `Handler` is where we actually enforce HTTP limits; but without `Handler` being a distinct type, any code path could simply do a `runExceptT $ runReader` and forget to enforce them. (As a rule of thumb, i am starting to consider any straggling `runReaderT` or `runExceptT` as a code smell: we should not stack / unstack monads haphazardly, and every layer should be an opaque `newtype` with a corresponding run function.) ## Further work In several places, i have left TODOs when i have encountered things that suggest that we should do further unrelated cleanups. I'll write down the follow-up steps, either in the aforementioned document or on slack. But, in short, at a glance, in approximate order, we could: - delete `ExecutionCtx` as it is only a subset of `ServerCtx`, and remove one more `runReaderT` call - delete `ServerConfigCtx` as it is only a subset of `ServerCtx`, and remove it from `RunCtx` - remove `ServerCtx` from `HandlerCtx`, and make it part of `AppContext`, or even make it the `AppContext` altogether (since, at least for the OSS version, `AppContext` is there again only a subset) - remove `CacheBuildParams` and `CacheBuild` altogether, as they're just a distinct stack that is a `ReaderT` on top of `IO` that contains, you guessed it, the same thing as `ServerCtx` - move `RunT` out of `RQL.Types` and rename it, since after the previous cleanups **it only contains `UserInfo`**; it could be bundled with the authentication service, made a small implementation detail in `Hasura.Server.Auth` - rename `PGMetadaStorageT` to something a bit more accurate, such as `App`, and enforce its IO base This would significantly simply our complex stack. From there, or in parallel, we can start moving existing dependencies as Services. For the purpose of supporting read replicas entitlement, we could move `MonadResolveSource` to a `SourceResolver` service, as attempted in #7653, and transform `UserAuthenticationM` into a `Authentication` service. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7736 GitOrigin-RevId: 68cce710eb9e7d752bda1ba0c49541d24df8209f
2023-02-22 18:53:52 +03:00
import Hasura.Services
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
import Hasura.Session
import Hasura.Tracing qualified as Tracing
-- Resolves a user specified `RemoteSchemaMetadata` into information rich `RemoteSchemaCtx`
-- However, given the nature of remote relationships, we cannot fully 'resolve' them, so
-- we resolve of remote relationships as much as possible.
buildRemoteSchemas ::
( ArrowChoice arr,
Inc.ArrowDistribute arr,
ArrowWriter (Seq (Either InconsistentMetadata MetadataDependency)) arr,
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
Inc.ArrowCache m arr,
MonadIO m,
MonadBaseControl IO m,
server: delete the `Cacheable` type class in favor of `Eq` What is the `Cacheable` type class about? ```haskell class Eq a => Cacheable a where unchanged :: Accesses -> a -> a -> Bool default unchanged :: (Generic a, GCacheable (Rep a)) => Accesses -> a -> a -> Bool unchanged accesses a b = gunchanged (from a) (from b) accesses ``` Its only method is an alternative to `(==)`. The added value of `unchanged` (and the additional `Accesses` argument) arises _only_ for one type, namely `Dependency`. Indeed, the `Cacheable (Dependency a)` instance is non-trivial, whereas every other `Cacheable` instance is completely boilerplate (and indeed either generated from `Generic`, or simply `unchanged _ = (==)`). The `Cacheable (Dependency a)` instance is the only one where the `Accesses` argument is not just passed onwards. The only callsite of the `unchanged` method is in the `ArrowCache (Rule m)` method. That is to say that the `Cacheable` type class is used to decide when we can re-use parts of the schema cache between Metadata operations. So what is the `Cacheable (Dependency a)` instance about? Normally, the output of a `Rule m a b` is re-used when the new input (of type `a`) is equal to the old one. But sometimes, that's too coarse: it might be that a certain `Rule m a b` only depends on a small part of its input of type `a`. A `Dependency` allows us to spell out what parts of `a` are being depended on, and these parts are recorded as values of types `Access a` in the state `Accesses`. If the input `a` changes, but not in a way that touches the recorded `Accesses`, then the output `b` of that rule can be re-used without recomputing. So now you understand _why_ we're passing `Accesses` to the `unchanged` method: `unchanged` is an equality check in disguise that just needs some additional context. But we don't need to pass `Accesses` as a function argument. We can use the `reflection` package to pass it as type-level context. So the core of this PR is that we change the instance declaration from ```haskell instance (Cacheable a) => Cacheable (Dependency a) where ``` to ```haskell instance (Given Accesses, Eq a) => Eq (Dependency a) where ``` and use `(==)` instead of `unchanged`. If you haven't seen `reflection` before: it's like a `MonadReader`, but it doesn't require a `Monad`. In order to pass the current `Accesses` value, instead of simply passing the `Accesses` as a function argument, we need to instantiate the `Given Accesses` context. We use the `give` method from the `reflection` package for that. ```haskell give :: forall r. Accesses -> (Given Accesses => r) -> r unchanged :: (Given Accesses => Eq a) => Accesses -> a -> a -> Bool unchanged accesses a b = give accesses (a == b) ``` With these three components in place, we can delete the `Cacheable` type class entirely. The remainder of this PR is just to remove the `Cacheable` type class and its instances. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6877 GitOrigin-RevId: 7125f5e11d856e7672ab810a23d5bf5ad176e77f
2022-11-21 19:33:56 +03:00
Eq remoteRelationshipDefinition,
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
ToJSON remoteRelationshipDefinition,
harmonize network manager handling ## Description ### I want to speak to the `Manager` Oh boy. This PR is both fairly straightforward and overreaching, so let's break it down. For most network access, we need a [`HTTP.Manager`](https://hackage.haskell.org/package/http-client-0.1.0.0/docs/Network-HTTP-Client-Manager.html). It is created only once, at the top level, when starting the engine, and is then threaded through the application to wherever we need to make a network call. As of main, the way we do this is not standardized: most of the GraphQL execution code passes it "manually" as a function argument throughout the code. We also have a custom monad constraint, `HasHttpManagerM`, that describes a monad's ability to provide a manager. And, finally, several parts of the code store the manager in some kind of argument structure, such as `RunT`'s `RunCtx`. This PR's first goal is to harmonize all of this: we always create the manager at the root, and we already have it when we do our very first `runReaderT`. Wouldn't it make sense for the rest of the code to not manually pass it anywhere, to not store it anywhere, but to always rely on the current monad providing it? This is, in short, what this PR does: it implements a constraint on the base monads, so that they provide the manager, and removes most explicit passing from the code. ### First come, first served One way this PR goes a tiny bit further than "just" doing the aforementioned harmonization is that it starts the process of implementing the "Services oriented architecture" roughly outlined in this [draft document](https://docs.google.com/document/d/1FAigqrST0juU1WcT4HIxJxe1iEBwTuBZodTaeUvsKqQ/edit?usp=sharing). Instead of using the existing `HasHTTPManagerM`, this PR revamps it into the `ProvidesNetwork` service. The idea is, again, that we should make all "external" dependencies of the engine, all things that the core of the engine doesn't care about, a "service". This allows us to define clear APIs for features, to choose different implementations based on which version of the engine we're running, harmonizes our many scattered monadic constraints... Which is why this service is called "Network": we can refine it, moving forward, to be the constraint that defines how all network communication is to operate, instead of relying on disparate classes constraint or hardcoded decisions. A comment in the code clarifies this intent. ### Side-effects? In my Haskell? This PR also unavoidably touches some other aspects of the codebase. One such example: it introduces `Hasura.App.AppContext`, named after `HasuraPro.Context.AppContext`: a name for the reader structure at the base level. It also transforms `Handler` from a type alias to a newtype, as `Handler` is where we actually enforce HTTP limits; but without `Handler` being a distinct type, any code path could simply do a `runExceptT $ runReader` and forget to enforce them. (As a rule of thumb, i am starting to consider any straggling `runReaderT` or `runExceptT` as a code smell: we should not stack / unstack monads haphazardly, and every layer should be an opaque `newtype` with a corresponding run function.) ## Further work In several places, i have left TODOs when i have encountered things that suggest that we should do further unrelated cleanups. I'll write down the follow-up steps, either in the aforementioned document or on slack. But, in short, at a glance, in approximate order, we could: - delete `ExecutionCtx` as it is only a subset of `ServerCtx`, and remove one more `runReaderT` call - delete `ServerConfigCtx` as it is only a subset of `ServerCtx`, and remove it from `RunCtx` - remove `ServerCtx` from `HandlerCtx`, and make it part of `AppContext`, or even make it the `AppContext` altogether (since, at least for the OSS version, `AppContext` is there again only a subset) - remove `CacheBuildParams` and `CacheBuild` altogether, as they're just a distinct stack that is a `ReaderT` on top of `IO` that contains, you guessed it, the same thing as `ServerCtx` - move `RunT` out of `RQL.Types` and rename it, since after the previous cleanups **it only contains `UserInfo`**; it could be bundled with the authentication service, made a small implementation detail in `Hasura.Server.Auth` - rename `PGMetadaStorageT` to something a bit more accurate, such as `App`, and enforce its IO base This would significantly simply our complex stack. From there, or in parallel, we can start moving existing dependencies as Services. For the purpose of supporting read replicas entitlement, we could move `MonadResolveSource` to a `SourceResolver` service, as attempted in #7653, and transform `UserAuthenticationM` into a `Authentication` service. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7736 GitOrigin-RevId: 68cce710eb9e7d752bda1ba0c49541d24df8209f
2023-02-22 18:53:52 +03:00
MonadError QErr m,
ProvidesNetwork m
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
) =>
Env.Environment ->
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles, Maybe (HashMap RemoteSchemaName BL.ByteString)),
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
[RemoteSchemaMetadataG remoteRelationshipDefinition]
)
`arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject)
buildRemoteSchemas env =
buildInfoMapPreservingMetadata _rsmName mkRemoteSchemaMetadataObject buildRemoteSchema
where
-- We want to cache this call because it fetches the remote schema over
-- HTTP, and we dont want to re-run that if the remote schema definition
-- hasnt changed.
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
buildRemoteSchema = Inc.cache proc ((invalidationKeys, orderedRoles, storedIntrospection), remoteSchema@(RemoteSchemaMetadata name defn _comment permissions relationships)) -> do
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
Inc.dependOn -< Inc.selectKeyD name invalidationKeys
remoteSchemaContextParts <-
(|
withRecordInconsistency
( liftEitherA <<< bindA
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
-< runExceptT
case M.lookup name =<< storedIntrospection of
Nothing -> noopTrace $ addRemoteSchemaP2Setup env name defn
Just rawIntro -> do
rsDef <- validateRemoteSchemaDef env defn
(ir, rsi) <- stitchRemoteSchema rawIntro name rsDef
pure (ir, rawIntro, rsi)
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
)
|) (mkRemoteSchemaMetadataObject remoteSchema)
case remoteSchemaContextParts of
Nothing -> returnA -< Nothing
Just (introspection, rawIntrospection, remoteSchemaInfo) -> do
-- we then resolve permissions
resolvedPermissions <- buildRemoteSchemaPermissions -< ((name, introspection, orderedRoles), fmap (name,) permissions)
-- resolve remote relationships
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
let transformedRelationships = relationships <&> \RemoteSchemaTypeRelationships {..} -> PartiallyResolvedRemoteRelationship _rstrsName <$> _rstrsRelationships
remoteSchemaContext =
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
RemoteSchemaCtx
{ _rscName = name,
_rscIntroOriginal = introspection,
_rscInfo = remoteSchemaInfo,
_rscRawIntrospectionResult = rawIntrospection,
_rscPermissions = resolvedPermissions,
_rscRemoteRelationships = transformedRelationships
}
returnA -< Just remoteSchemaContext
-- TODO continue propagating MonadTrace up calls so that we can get tracing
-- for remote schema introspection. This will require modifying CacheBuild.
noopTrace = Tracing.runTraceTWithReporter Tracing.noReporter Tracing.sampleNever "buildSchemaCacheRule"
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
mkRemoteSchemaMetadataObject remoteSchema =
MetadataObject (MORemoteSchema (_rsmName remoteSchema)) (toJSON remoteSchema)
-- | Resolves a RemoteSchemaPermission metadata object into a 'GraphQL schema'.
buildRemoteSchemaPermissions ::
( ArrowChoice arr,
Inc.ArrowDistribute arr,
ArrowWriter (Seq (Either InconsistentMetadata MetadataDependency)) arr,
server: plumb `StoredIntrospection` while building the Schema Cache We'd like to be able to build a Schema Cache from only serializable data. We already have Metadata. The data that's missing to build a Schema Cache is referred to as "stored introspection", and this includes: - DB introspection - User-defined enum values (i.e. contents of specific DB tables) - Remote schema introspection This PR introduces a new `StoredIntrospection` container that holds that data, and plumbs it through to the right parts of the schema cache building process, so that stored introspection can be used as a substitute for fresh introspection requests against live data sources. The serialization of `StoredIntrospection` is intended to be straightforward: just take the serialized source introspection results, and put them in an appropriate JSON object. Though I don't think that this PR achieves that entirely. In order for `StoredIntrospection` to be deserializable (through `aeson` instances), while keeping the required code changes low, this piggy-backs off of the `ResolvedSource` data type. `ResolvedSource` is _almost_ exactly what we want, and _almost_ deserializable, so this PR brings it across the finish line by moving a few things out of that type, and adding a `FromJSON (RawFunctionInfo b)` context to the `Backend` type class. [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-270]: https://hasurahq.atlassian.net/browse/PLAT-270?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ [PLAT-276]: https://hasurahq.atlassian.net/browse/PLAT-276?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7053 GitOrigin-RevId: 5001b4ea086195cb5e65886747eac2a0a657b64c
2023-01-20 17:51:11 +03:00
ArrowKleisli m arr,
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
MonadError QErr m
) =>
-- this ridiculous duplication of [(RemoteSchemaName, RemoteSchemaPermissionMetadata)]
-- instead of just [RemoteSchemaName] is because buildInfoMap doesn't pass `e` to the
-- mkMetadataObject function. However, that change is very invasive.
((RemoteSchemaName, IntrospectionResult, OrderedRoles), [(RemoteSchemaName, RemoteSchemaPermissionMetadata)]) `arr` M.HashMap RoleName IntrospectionResult
buildRemoteSchemaPermissions = proc ((remoteSchemaName, originalIntrospection, orderedRoles), permissions) -> do
metadataPermissionsMap <- do
buildInfoMap (_rspmRole . snd) mkRemoteSchemaPermissionMetadataObject buildRemoteSchemaPermission
-<
(originalIntrospection, permissions)
-- convert to the intermediate form `CheckPermission` whose `Semigroup`
-- instance is used to combine permissions
let metadataCheckPermissionsMap = CPDefined <$> metadataPermissionsMap
allRolesUnresolvedPermissionsMap <-
bindA
-<
foldM
( \accumulatedRolePermMap (Role roleName (ParentRoles parentRoles)) -> do
rolePermission <- onNothing (M.lookup roleName accumulatedRolePermMap) $ do
parentRolePermissions <-
for (toList parentRoles) $ \role ->
onNothing (M.lookup role accumulatedRolePermMap) $
throw500 $
"remote schema permissions: bad ordering of roles, could not find the permission of role: " <>> role
let combinedPermission = sconcat <$> nonEmpty parentRolePermissions
pure $ fromMaybe CPUndefined combinedPermission
pure $ M.insert roleName rolePermission accumulatedRolePermMap
)
metadataCheckPermissionsMap
(_unOrderedRoles orderedRoles)
-- traverse through `allRolesUnresolvedPermissionsMap` to record any inconsistencies (if exists)
resolvedPermissions <-
interpretWriter
-< for (M.toList allRolesUnresolvedPermissionsMap) \(roleName, checkPermission) -> do
let inconsistentRoleEntity = InconsistentRemoteSchemaPermission remoteSchemaName
resolvedCheckPermission <- resolveCheckPermission checkPermission roleName inconsistentRoleEntity
return (roleName, resolvedCheckPermission)
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
returnA -< catMaybes $ M.fromList resolvedPermissions
where
buildRemoteSchemaPermission = proc (originalIntrospection, (remoteSchemaName, remoteSchemaPerm)) -> do
let RemoteSchemaPermissionMetadata roleName defn _ = remoteSchemaPerm
metadataObject = mkRemoteSchemaPermissionMetadataObject (remoteSchemaName, remoteSchemaPerm)
schemaObject = SORemoteSchemaPermission remoteSchemaName roleName
providedSchemaDoc = _rspdSchema defn
addPermContext err = "in remote schema permission for role " <> roleName <<> ": " <> err
(|
withRecordInconsistency
( do
(resolvedSchemaIntrospection, dependency) <-
liftEitherA <<< bindA
-<
runExceptT $ modifyErr addPermContext $ resolveRoleBasedRemoteSchema roleName remoteSchemaName originalIntrospection providedSchemaDoc
recordDependencies -< (metadataObject, schemaObject, pure dependency)
returnA -< resolvedSchemaIntrospection
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
)
|) metadataObject
mkRemoteSchemaPermissionMetadataObject ::
(RemoteSchemaName, RemoteSchemaPermissionMetadata) ->
MetadataObject
mkRemoteSchemaPermissionMetadataObject (rsName, (RemoteSchemaPermissionMetadata roleName defn _)) =
let objectId = MORemoteSchemaPermissions rsName roleName
in MetadataObject objectId $ toJSON defn
addRemoteSchemaP2Setup ::
harmonize network manager handling ## Description ### I want to speak to the `Manager` Oh boy. This PR is both fairly straightforward and overreaching, so let's break it down. For most network access, we need a [`HTTP.Manager`](https://hackage.haskell.org/package/http-client-0.1.0.0/docs/Network-HTTP-Client-Manager.html). It is created only once, at the top level, when starting the engine, and is then threaded through the application to wherever we need to make a network call. As of main, the way we do this is not standardized: most of the GraphQL execution code passes it "manually" as a function argument throughout the code. We also have a custom monad constraint, `HasHttpManagerM`, that describes a monad's ability to provide a manager. And, finally, several parts of the code store the manager in some kind of argument structure, such as `RunT`'s `RunCtx`. This PR's first goal is to harmonize all of this: we always create the manager at the root, and we already have it when we do our very first `runReaderT`. Wouldn't it make sense for the rest of the code to not manually pass it anywhere, to not store it anywhere, but to always rely on the current monad providing it? This is, in short, what this PR does: it implements a constraint on the base monads, so that they provide the manager, and removes most explicit passing from the code. ### First come, first served One way this PR goes a tiny bit further than "just" doing the aforementioned harmonization is that it starts the process of implementing the "Services oriented architecture" roughly outlined in this [draft document](https://docs.google.com/document/d/1FAigqrST0juU1WcT4HIxJxe1iEBwTuBZodTaeUvsKqQ/edit?usp=sharing). Instead of using the existing `HasHTTPManagerM`, this PR revamps it into the `ProvidesNetwork` service. The idea is, again, that we should make all "external" dependencies of the engine, all things that the core of the engine doesn't care about, a "service". This allows us to define clear APIs for features, to choose different implementations based on which version of the engine we're running, harmonizes our many scattered monadic constraints... Which is why this service is called "Network": we can refine it, moving forward, to be the constraint that defines how all network communication is to operate, instead of relying on disparate classes constraint or hardcoded decisions. A comment in the code clarifies this intent. ### Side-effects? In my Haskell? This PR also unavoidably touches some other aspects of the codebase. One such example: it introduces `Hasura.App.AppContext`, named after `HasuraPro.Context.AppContext`: a name for the reader structure at the base level. It also transforms `Handler` from a type alias to a newtype, as `Handler` is where we actually enforce HTTP limits; but without `Handler` being a distinct type, any code path could simply do a `runExceptT $ runReader` and forget to enforce them. (As a rule of thumb, i am starting to consider any straggling `runReaderT` or `runExceptT` as a code smell: we should not stack / unstack monads haphazardly, and every layer should be an opaque `newtype` with a corresponding run function.) ## Further work In several places, i have left TODOs when i have encountered things that suggest that we should do further unrelated cleanups. I'll write down the follow-up steps, either in the aforementioned document or on slack. But, in short, at a glance, in approximate order, we could: - delete `ExecutionCtx` as it is only a subset of `ServerCtx`, and remove one more `runReaderT` call - delete `ServerConfigCtx` as it is only a subset of `ServerCtx`, and remove it from `RunCtx` - remove `ServerCtx` from `HandlerCtx`, and make it part of `AppContext`, or even make it the `AppContext` altogether (since, at least for the OSS version, `AppContext` is there again only a subset) - remove `CacheBuildParams` and `CacheBuild` altogether, as they're just a distinct stack that is a `ReaderT` on top of `IO` that contains, you guessed it, the same thing as `ServerCtx` - move `RunT` out of `RQL.Types` and rename it, since after the previous cleanups **it only contains `UserInfo`**; it could be bundled with the authentication service, made a small implementation detail in `Hasura.Server.Auth` - rename `PGMetadaStorageT` to something a bit more accurate, such as `App`, and enforce its IO base This would significantly simply our complex stack. From there, or in parallel, we can start moving existing dependencies as Services. For the purpose of supporting read replicas entitlement, we could move `MonadResolveSource` to a `SourceResolver` service, as attempted in #7653, and transform `UserAuthenticationM` into a `Authentication` service. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7736 GitOrigin-RevId: 68cce710eb9e7d752bda1ba0c49541d24df8209f
2023-02-22 18:53:52 +03:00
(QErrM m, MonadIO m, ProvidesNetwork m, Tracing.MonadTrace m) =>
scaffolding for remote-schemas module The main aim of the PR is: 1. To set up a module structure for 'remote-schemas' package. 2. Move parts by the remote schema codebase into the new module structure to validate it. ## Notes to the reviewer Why a PR with large-ish diff? 1. We've been making progress on the MM project but we don't yet know long it is going to take us to get to the first milestone. To understand this better, we need to figure out the unknowns as soon as possible. Hence I've taken a stab at the first two items in the [end-state](https://gist.github.com/0x777/ca2bdc4284d21c3eec153b51dea255c9) document to figure out the unknowns. Unsurprisingly, there are a bunch of issues that we haven't discussed earlier. These are documented in the 'open questions' section. 1. The diff is large but that is only code moved around and I've added a section that documents how things are moved. In addition, there are fair number of PR comments to help with the review process. ## Changes in the PR ### Module structure Sets up the module structure as follows: ``` Hasura/ RemoteSchema/ Metadata/ Types.hs SchemaCache/ Types.hs Permission.hs RemoteRelationship.hs Build.hs MetadataAPI/ Types.hs Execute.hs ``` ### 1. Types representing metadata are moved Types that capture metadata information (currently scattered across several RQL modules) are moved into `Hasura.RemoteSchema.Metadata.Types`. - This new module only depends on very 'core' modules such as `Hasura.Session` for the notion of roles and `Hasura.Incremental` for `Cacheable` typeclass. - The requirement on database modules is avoided by generalizing the remote schemas metadata to accept an arbitrary 'r' for a remote relationship definition. ### 2. SchemaCache related types and build logic have been moved Types that represent remote schemas information in SchemaCache are moved into `Hasura.RemoteSchema.SchemaCache.Types`. Similar to `H.RS.Metadata.Types`, this module depends on 'core' modules except for `Hasura.GraphQL.Parser.Variable`. It has something to do with remote relationships but I haven't spent time looking into it. The validation of 'remote relationships to remote schema' is also something that needs to be looked at. Rips out the logic that builds remote schema's SchemaCache information from the monolithic `buildSchemaCacheRule` and moves it into `Hasura.RemoteSchema.SchemaCache.Build`. Further, the `.SchemaCache.Permission` and `.SchemaCache.RemoteRelationship` have been created from existing modules that capture schema cache building logic for those two components. This was a fair amount of work. On main, currently remote schema's SchemaCache information is built in two phases - in the first phase, 'permissions' and 'remote relationships' are ignored and in the second phase they are filled in. While remote relationships can only be resolved after partially resolving sources and other remote schemas, the same isn't true for permissions. Further, most of the work that is done to resolve remote relationships can be moved to the first phase so that the second phase can be a very simple traversal. This is the approach that was taken - resolve permissions and as much as remote relationships information in the first phase. ### 3. Metadata APIs related types and build logic have been moved The types that represent remote schema related metadata APIs and the execution logic have been moved to `Hasura.RemoteSchema.MetadataAPI.Types` and `.Execute` modules respectively. ## Open questions: 1. `Hasura.RemoteSchema.Metadata.Types` is so called because I was hoping that all of the metadata related APIs of remote schema can be brought in at `Hasura.RemoteSchema.Metadata.API`. However, as metadata APIs depended on functions from `SchemaCache` module (see [1](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L55) and [2](https://github.com/hasura/graphql-engine-mono/blob/ceba6d62264603ee5d279814677b29bcc43ecaea/server/src-lib/Hasura/RQL/DDL/RemoteSchema.hs#L91), it made more sense to create a separate top-level module for `MetadataAPI`s. Maybe we can just have `Hasura.RemoteSchema.Metadata` and get rid of the extra nesting or have `Hasura.RemoteSchema.Metadata.{Core,Permission,RemoteRelationship}` if we want to break them down further. 1. `buildRemoteSchemas` in `H.RS.SchemaCache.Build` has the following type: ```haskell buildRemoteSchemas :: ( ArrowChoice arr, Inc.ArrowDistribute arr, ArrowWriter (Seq CollectedInfo) arr, Inc.ArrowCache m arr, MonadIO m, HasHttpManagerM m, Inc.Cacheable remoteRelationshipDefinition, ToJSON remoteRelationshipDefinition, MonadError QErr m ) => Env.Environment -> ( (Inc.Dependency (HashMap RemoteSchemaName Inc.InvalidationKey), OrderedRoles), [RemoteSchemaMetadataG remoteRelationshipDefinition] ) `arr` HashMap RemoteSchemaName (PartiallyResolvedRemoteSchemaCtxG remoteRelationshipDefinition, MetadataObject) ``` Note the dependence on `CollectedInfo` which is defined as ```haskell data CollectedInfo = CIInconsistency InconsistentMetadata | CIDependency MetadataObject -- ^ for error reporting on missing dependencies SchemaObjId SchemaDependency deriving (Eq) ``` this pretty much means that remote schemas is dependent on types from databases, actions, .... How do we fix this? Maybe introduce a typeclass such as `ArrowCollectRemoteSchemaDependencies` which is defined in `Hasura.RemoteSchema` and then implemented in graphql-engine? 1. The dependency on `buildSchemaCacheFor` in `.MetadataAPI.Execute` which has the following signature: ```haskell buildSchemaCacheFor :: (QErrM m, CacheRWM m, MetadataM m) => MetadataObjId -> MetadataModifier -> ``` This can be easily resolved if we restrict what the metadata APIs are allowed to do. Currently, they operate in an unfettered access to modify SchemaCache (the `CacheRWM` constraint): ```haskell runAddRemoteSchema :: ( QErrM m, CacheRWM m, MonadIO m, HasHttpManagerM m, MetadataM m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m EncJSON ``` This should instead be changed to restrict remote schema APIs to only modify remote schema metadata (but has access to the remote schemas part of the schema cache), this dependency is completely removed. ```haskell runAddRemoteSchema :: ( QErrM m, MonadIO m, HasHttpManagerM m, MonadReader RemoteSchemasSchemaCache m, MonadState RemoteSchemaMetadata m, Tracing.MonadTrace m ) => Env.Environment -> AddRemoteSchemaQuery -> m RemoteSchemeMetadataObjId ``` The idea is that the core graphql-engine would call these functions and then call `buildSchemaCacheFor`. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6291 GitOrigin-RevId: 51357148c6404afe70219afa71bd1d59bdf4ffc6
2022-10-21 06:13:07 +03:00
Env.Environment ->
RemoteSchemaName ->
RemoteSchemaDef ->
m (IntrospectionResult, BL.ByteString, RemoteSchemaInfo)
addRemoteSchemaP2Setup env name def = do
rsi <- validateRemoteSchemaDef env def
harmonize network manager handling ## Description ### I want to speak to the `Manager` Oh boy. This PR is both fairly straightforward and overreaching, so let's break it down. For most network access, we need a [`HTTP.Manager`](https://hackage.haskell.org/package/http-client-0.1.0.0/docs/Network-HTTP-Client-Manager.html). It is created only once, at the top level, when starting the engine, and is then threaded through the application to wherever we need to make a network call. As of main, the way we do this is not standardized: most of the GraphQL execution code passes it "manually" as a function argument throughout the code. We also have a custom monad constraint, `HasHttpManagerM`, that describes a monad's ability to provide a manager. And, finally, several parts of the code store the manager in some kind of argument structure, such as `RunT`'s `RunCtx`. This PR's first goal is to harmonize all of this: we always create the manager at the root, and we already have it when we do our very first `runReaderT`. Wouldn't it make sense for the rest of the code to not manually pass it anywhere, to not store it anywhere, but to always rely on the current monad providing it? This is, in short, what this PR does: it implements a constraint on the base monads, so that they provide the manager, and removes most explicit passing from the code. ### First come, first served One way this PR goes a tiny bit further than "just" doing the aforementioned harmonization is that it starts the process of implementing the "Services oriented architecture" roughly outlined in this [draft document](https://docs.google.com/document/d/1FAigqrST0juU1WcT4HIxJxe1iEBwTuBZodTaeUvsKqQ/edit?usp=sharing). Instead of using the existing `HasHTTPManagerM`, this PR revamps it into the `ProvidesNetwork` service. The idea is, again, that we should make all "external" dependencies of the engine, all things that the core of the engine doesn't care about, a "service". This allows us to define clear APIs for features, to choose different implementations based on which version of the engine we're running, harmonizes our many scattered monadic constraints... Which is why this service is called "Network": we can refine it, moving forward, to be the constraint that defines how all network communication is to operate, instead of relying on disparate classes constraint or hardcoded decisions. A comment in the code clarifies this intent. ### Side-effects? In my Haskell? This PR also unavoidably touches some other aspects of the codebase. One such example: it introduces `Hasura.App.AppContext`, named after `HasuraPro.Context.AppContext`: a name for the reader structure at the base level. It also transforms `Handler` from a type alias to a newtype, as `Handler` is where we actually enforce HTTP limits; but without `Handler` being a distinct type, any code path could simply do a `runExceptT $ runReader` and forget to enforce them. (As a rule of thumb, i am starting to consider any straggling `runReaderT` or `runExceptT` as a code smell: we should not stack / unstack monads haphazardly, and every layer should be an opaque `newtype` with a corresponding run function.) ## Further work In several places, i have left TODOs when i have encountered things that suggest that we should do further unrelated cleanups. I'll write down the follow-up steps, either in the aforementioned document or on slack. But, in short, at a glance, in approximate order, we could: - delete `ExecutionCtx` as it is only a subset of `ServerCtx`, and remove one more `runReaderT` call - delete `ServerConfigCtx` as it is only a subset of `ServerCtx`, and remove it from `RunCtx` - remove `ServerCtx` from `HandlerCtx`, and make it part of `AppContext`, or even make it the `AppContext` altogether (since, at least for the OSS version, `AppContext` is there again only a subset) - remove `CacheBuildParams` and `CacheBuild` altogether, as they're just a distinct stack that is a `ReaderT` on top of `IO` that contains, you guessed it, the same thing as `ServerCtx` - move `RunT` out of `RQL.Types` and rename it, since after the previous cleanups **it only contains `UserInfo`**; it could be bundled with the authentication service, made a small implementation detail in `Hasura.Server.Auth` - rename `PGMetadaStorageT` to something a bit more accurate, such as `App`, and enforce its IO base This would significantly simply our complex stack. From there, or in parallel, we can start moving existing dependencies as Services. For the purpose of supporting read replicas entitlement, we could move `MonadResolveSource` to a `SourceResolver` service, as attempted in #7653, and transform `UserAuthenticationM` into a `Authentication` service. PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7736 GitOrigin-RevId: 68cce710eb9e7d752bda1ba0c49541d24df8209f
2023-02-22 18:53:52 +03:00
fetchRemoteSchema env name rsi