This fixes the simple HLint warnings, and adds a few suppressions to avoid noise.
The suppressions don't really solve the problems, but I think the warnings here are quite benign and I'm uncomfortable with how likely I would be to introduce a bug during refactoring.
In the case of _pg-client_ and _resource-pool_, we can't use the recommended functions anyway, and there doesn't seem to be a way to tell HLint to ignore entire packages.
I have updated the `make` targets to only fail if errors or warnings are found, not suggestions. This brings it in line with the CI job.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8910
GitOrigin-RevId: 596277b4ae5833876fc3f43875208c1279518a59
The simplification will allow us to avoid a few `MonadError QErr m` constsraints in the future - this effect can be created locally instead of reusing a global one.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8729
GitOrigin-RevId: 851e28b1f5bfe4c47da43fa324714a941ef25c57
## Description
This change adds support for nested object fields in HGE IR and Schema Cache, the Data Connectors backend and API, and the MongoDB agent.
### Data Connector API changes
- The `/schema` endpoint response now includes an optional set of GraphQL type definitions. Table column types can refer to these definitions by name.
- Queries can now include a new field type `object` which contains a column name and a nested query. This allows querying into a nested object within a field.
### MongoDB agent changes
- Add support for querying into nested documents using the new `object` field type.
### HGE changes
- The `Backend` type class has a new type family `XNestedObjects b` which controls whether or not a backend supports querying into nested objects. This is currently enabled only for the `DataConnector` backend.
- For backends that support nested objects, the `FieldInfo` type gets a new constructor `FINestedObject`, and the `AnnFieldG` type gets a new constructor `AFNestedObject`.
- If the DC `/schema` endpoint returns any custom GraphQL type definitions they are stored in the `TableInfo` for each table in the source.
- During schema cache building, the function `addNonColumnFields` will check whether any column types match custom GraphQL object types stored in the `TableInfo`. If so, they are converted into `FINestedObject` instead of `FIColumn` in the `FieldInfoMap`.
- When building the `FieldParser`s from `FieldInfo` (function `fieldSelection`) any `FINestedObject` fields are converted into nested object parsers returning `AFNestedObject`.
- The `DataConnector` query planner converts `AFNestedObject` fields into `object` field types in the query sent to the agent.
## Limitations
### HGE not yet implemented:
- Support for nested arrays
- Support for nested objects/arrays in mutations
- Support for nested objects/arrays in order-by
- Support for filters (`where`) in nested objects/arrays
- Support for adding custom GraphQL types via track table metadata API
- Support for interface and union types
- Tests for nested objects
### Mongo agent not yet implemented:
- Generate nested object types from validation schema
- Support for aggregates
- Support for order-by
- Configure agent port
- Build agent in CI
- Agent tests for nested objects and MongoDB agent
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7844
GitOrigin-RevId: aec9ec1e4216293286a68f9b1af6f3f5317db423
### Description
This PR removes `ServerConfigCtx` and `HasServerConfigCtx`. Instead, it favours different approaches:
- when the code was only using one field, it passes that field explicitly (usually `SQLGenCtx` or `CheckFeatureFlag`)
- when the code was using several fields, but in only one function, it inlines
- for the cache build, it introduces `CacheStaticConfig` and `CacheDynamicConfig`, which are subsets of `AppEnv` and `AppContext` respectively
The main goal of this is to help with the modularization of the engine: as `ServerConfigCtx` had fields whose types were imported from several unrelated parts of the engine, using it tied together parts of the engine that should not be aware of one another (such as tying together `Hasura.LogicalModel` and `Hasura.GraphQL.Schema`).
The bulk of this PR is a change to the cache build, as a follow up to #8509: instead of giving the entire `ServerConfigCtx` as a incremental rule argument, we only give the new `CacheDynamicConfig` struct, which has fewer fields. The other required fields, that were coming from the `AppEnv`, are now given via the `HasCacheStaticConfig` constraint, which is a "subset" of `HasAppEnv`.
(Some further work could include moving `StringifyNumbers` out of `GraphQL.Schema.Options`, given how it is used all across the codebase, including in `RQL.DML`.)
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8513
GitOrigin-RevId: 818cbcd71494e3cd946b06adbb02ca328a8a298e
This PR reverts the following two commits:
1. https://github.com/hasura/graphql-engine-mono/pull/8287
2. https://github.com/hasura/graphql-engine-mono/pull/8467
We are undoing a migration that was done on `hdb_catalog.event_log` table which was done in d4ae6a517da63f2f43567dc16fda135b3cd1d7e6 . And as such, users who were using event triggers on that version will come across the error:
```json
{"detail":{"info":{"code":"not-supported","error":"Expected source catalog version <= 3, but the current version is 4","path":"$"},"kind":"catalog_migrate"},"level":"error","timestamp":"2023-03-28T10:17:24.289+0530","type":"startup"}
{"code":"not-supported","error":"Expected source catalog version <= 3, but the current version is 4","path":"$"}
```
To fix these errors please run the following SQL on the source where event triggers were created on:
```
UPDATE hdb_catalog.hdb_source_catalog_version SET version = 3, upgraded_on= NOW();
ALTER table hdb_catalog.event_log ALTER COLUMN created_at SET DEFAULT NOW();
ALTER table hdb_catalog.event_invocation_logs ALTER COLUMN created_at SET DEFAULT NOW();
```
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8534
GitOrigin-RevId: b6bbcce0163c8beed80619d3cea056e643b8c180
## Description
This PR is a incremental step towards achieving the goal of #8344. It is a less ambitious version of #8484.
This PR removes all references to `HasServerConfigCtx` from the cache build and removes `ServerConfigCtx` from `CacheBuildParams`, making `ServerConfigCtx` an argument being passed around manually instead. This has several benefits: by making it an arrow argument, we now properly integrate the fields that change over time in the dependency framework, as they should be, and we can clean up some of the top-level app code.
## Implementation
In practice, this PR introduces a `HasServerConfigCtx` instance for `CacheRWT`, the monad we use to build the cache, so we can retrieve the `ServerConfigCtx` in the implementation of `CacheRWM`. This contributes to reducing the amount of `HasServerConfigCtx` in the code: we can remove `SchemaUpdateT` altogether, and we can remove the `HasServerConfigCtx` instance of `Handler`. This makes `HasServerConfigCtx` almost **an implementation detail of the Metadata API**.
This first step is enough to achieve the goal of #8344: we can now build the schema cache in the app monad, since we no longer rely on `HasServerConfigCtx` to build it.
## Drawbacks
This PR does not attempt to remove the use of `ServerConfigCtx` itself in the schema cache build: doing so would make this PR much much bigger. Ideally, to avoid having all the static fields given as arrow-ish arguments to the cache, we could depend on `HasAppEnv` in the cache build, and use `AppContext` as an arrow argument. But making the cache build depend on the full `AppEnv` and `AppContext` creates a lot of circular imports; and since removing `ServerConfigCtx` itself isn't required to achieve #8344, this PR keeps it wholesale and defers cleaning it to a future PR.
A negative consequence of this is that we need an `Eq` instance on `ServerConfigCtx`, and that instance is inelegant.
## Future work
There are several further steps we can take in parallel after this is merged. First, again, we can make a new version of #8344, removing `CacheBuild`, FINALLY. As for `ServerConfigCtx`, we can split it / rename it to make ad-hoc structures. If it turns out that `ServerConfigCtx` is only ever used for the schema cache build, we could split it between `CacheBuildEnv` and `CacheBuildContext`, which will be subsets of `AppEnv` and `AppContext`, avoiding import loops.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8509
GitOrigin-RevId: 01b37cc3fd3490d6b117701e22fc4ac88b62b6b5
- Derive a few `instance`s
- Delete some dead code (methods and types)
- Delete some `INLINE` pragmas that are unlikely to have a big effect
- Monomorphize Postgres `LISTEN` code to avoid effect juggling
- Generalize some methods in `pg-client` so that others can be simplified
- Handle errors differently for `TxET` to deduplicate code
- Use `hoist` instead of specialized combinators such as `mapActionT`
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/8130
GitOrigin-RevId: bc1e908b6c0869f440a214a76744e92d40fea1e6
This PR is on top of #7789.
### Description
This PR entirely rewrites the API of the Tracing library, to make `interpTraceT` a thing of the past. Before this change, we ran traces by sticking a `TraceT` on top of whatever we were doing. This had several major drawbacks:
- we were carrying a bunch of `TraceT` across the codebase, and the entire codebase had to know about it
- we needed to carry a second class constraint around (`HasReporterM`) to be able to run all of those traces
- we kept having to do stack rewriting with `interpTraceT`, which went from inconvenient to horrible
- we had to declare several behavioral instances on `TraceT m`
This PR rewrite all of `Tracing` using a more conventional model: there is ONE `TraceT` at the bottom of the stack, and there is an associated class constraint `MonadTrace`: any part of the code that happens to satisfy `MonadTrace` is able to create new traces. We NEVER have to do stack rewriting, `interpTraceT` is gone, and `TraceT` and `Reporter` become implementation details that 99% of the code is blissfully unaware of: code that needs to do tracing only needs to declare that the monad in which it operates implements `MonadTrace`.
In doing so, this PR revealed **several bugs in the codebase**: places where we were expecting to trace something, but due to the default instance of `HasReporterM IO` we would actually not do anything. This PR also splits the code of `Tracing` in more byte-sized modules, with the goal of potentially moving to `server/lib` down the line.
### Remaining work
This PR is a draft; what's left to do is:
- [x] make Pro compile; i haven't updated `HasuraPro/Main` yet
- [x] document Tracing by writing a note that explains how to use the library, and the meaning of "reporter", "trace" and "span", as well as the pitfalls
- [x] discuss some of the trade-offs in the implementation, which is why i'm opening this PR already despite it not fully building yet
- [x] it depends on #7789 being merged first
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7791
GitOrigin-RevId: cadd32d039134c93ddbf364599a2f4dd988adea8
## 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
### Description
Each Backend executes queries against the database in a slightly different stack: Postgres uses its own `TXeT`, MSSQL uses a variant of it, BigQuery is simply in `ExceptT QErr IO`... To accommodate those variations, we had originally introduced an `ExecutionMonad b` type family in `BackendExecute`, allowing each backend to describe its own stack. It was then up to that backend's `BackendTransport` instance to implement running said stack, and converting the result back into our main app monad.
However, this was not without complications: `TraceT` is one of them: as it usually needs to be on the top of the stack, converting from one stack to the other implies the use `interpTraceT`, which is quite monstrous. Furthermore, as part of the Entitlement Services work, we're trying to move to a "Services" architecture in which the entire engine runs in one base monad, that delegates features and dependencies to monad constraints; and as a result we'd like to minimize the number of different monad stacks we have to maintain and translate from and to in the codebase.
To improve things, this PR changes `ExecutionMonad b` from an _absolute_ stack to a _relative_ one: i.e.: what needs to be stacked on top of our base monad for the execution. In `Transport`, we then only need to pop the top of the stack, and voila. This greatly simplifies the implementation of the backends, as there's no longer any need to do any stack transformation: MySQL's implementation becomes a `runIdentityT`! This also removes most mentions of `TraceT` from the execution code since it's no longer required: we can rely on the base monad's existing `MonadTrace` constraint.
To continue encapsulating monadic actions in `DBStepInfo` and avoid threading a bunch of `forall` all over the place, this PR introduces a small local helper: `OnBaseMonad`. One only downside of all this is that this requires adding `MonadBaseControl IO m` constraint all over the place: previously, we would run directly on `IO` and lift, and would therefore not need to bring that constraint all the way.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7789
GitOrigin-RevId: e9b2e431c5c47fa9851abf87545c0415ff6d1a12
Basic MongoDB agent. This is intended as a starting point for playing with nested documents in a MongoDB back end. Currently supports basic queries with projections, where expressions, limit and offset. No support for joins, aggregates or mutations.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7840
GitOrigin-RevId: 3f03b8416c95acf2b68da1db56cbe36a513a4bde
