## Description
Some of the documentation/organizational changes I was putting into the suggestions for #3624 were a bit too convoluted for GitHub's suggestion interface, so I'm putting them here instead.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3910
Co-authored-by: Solomon <24038+solomon-b@users.noreply.github.com>
GitOrigin-RevId: 06e0cb08bd18e7f8b21452df0697cfd80bc56fde
### Motivation
#2338 introduced a way to validate REST queries against the metadata after a change, to properly report any inconsistency that would emerge from a change in the underlying structure of our schema. However, the way this was done was quite complex and error-prone. Namely: we would use the generated schema parsers to statically execute an introspection query, similar to the one we use for remote schemas, then parse the resulting bytestring as it were coming from a remote schema.
This led to several issues: the code was using remote schema primitives, and was associated with remote schema code, despite being unrelated, which led to absurd situations like creating fake `Variable`s whose type was also their name. A lot of the code had to deal with the fact that we might fail to re-parse our own schema. Additionally, some of it was dead code, that for some reason GHC did not warn about? But more fundamentally, this architecture decision creates a dependency between unrelated pieces of the engine: modifying the internal processing of root fields or the introspection of remote schemas now risks impacting the unrelated `OpenAPI` feature.
### Description
This PR decouples that process from the remote schema introspection logic and from the execution engine by making `Analyse` and `OpenAPI` work on the generic `G.SchemaIntrospection` instead. To accomplish this, it:
- adds `GraphQL.Parser.Schema.Convert`, to convert from our "live" schema back to a flat `SchemaIntrospection`
- persists in the schema cache the `admin` introspection generated when building the schema, and uses it both for validation and for generating the `OpenAPI`.
### Known issues and limitations
This adds a bit of memory pressure to the engine, as we persist the entire schema in the schema cache. This might be acceptable in the short-term, but we have several potential ideas going forward should this be a problem:
- cache the result of `Analyze`: when it becomes possible to build the `OpenAPI` purely with the result of `Analyze` without any additional schema information, then we could cache that instead, reducing the footprint
- caching the `OpenAPI`: if it doesn't need to change every time the endpoint is queried, then it should be possible to cache the entire `OpenAPI` object instead of the schema
- cache a copy of the `FieldParsers` used to generate the schema: as those are persisted through the GraphQL `Context`, and are the only input required to generate the `Schema`, making them accessible in the schema cache would allow us to have the exact same feature with no additional memory cost, at the price of a slightly slower and more complicated process (need to rebuild the `Schema` every time we query the OpenAPI endpoint)
- cache nothing at all, and rebuild the admin schema from scratch every time.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3962
Co-authored-by: paritosh-08 <85472423+paritosh-08@users.noreply.github.com>
GitOrigin-RevId: a8b9808170b231fdf6787983b4a9ed286cde27e0
### Description
This is it! This PR enables the Metadata API for remote relationships from remote schemas, adds tests, ~~adds documentation~~, adds an entry to the Changelog. This is the release PR that enables the feature.
### Checklist
- [ ] Tests:
- [x] RS-to-Postgres (high level)
- [x] RS-to-RS (high level)
- [x] From RS specifically (testing for edge cases)
- [x] Metadata API tests
- [ ] Unit testing the actual engine?
- [x] Changelog entry
- [ ] Documentation?
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3974
Co-authored-by: Vamshi Surabhi <6562944+0x777@users.noreply.github.com>
Co-authored-by: Vishnu Bharathi <4211715+scriptnull@users.noreply.github.com>
Co-authored-by: jkachmar <8461423+jkachmar@users.noreply.github.com>
GitOrigin-RevId: c9aebf12e6eebef8d264ea831a327b968d4be9d2
### Description
This very small PR fixes an error introduced in #3811, when changing the collision detection code: we were properly doing collision detection for remote schemas for the unauthenticated context, and also removing remote relationships... but then we were not using the result to build the schema.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3986
GitOrigin-RevId: 26a5553bf82574f2764fd594b0616dfea95a4757
- remove an unused return value
- untangle database query logic slightly
- rename printErrExit functions, and use them more consistently
- simplify the top-level exception handling
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3900
GitOrigin-RevId: a6727c6f899aed00e6a04bd822727341fd51acc4
### Description
This PR extends the `RemoteSchema` parsers to also include remote relationships. This include a significant refactoring of the top level schema building blocks, since remote schemas can no longer be built in isolation: they have to be built within the same run of `MonadSchema` as the sources. It is originally taken from the changes in #3069 and was slightly adapted.
I highly recommend turning OFF whitespace in the Github UI for `Schema.hs`, since I've adjusted the indentation of two large functions.
### Warning
Given the lack of a feature flag, this PR technically **enables the feature**. While the metadata API is not plugged in, a savvy user could use `replace_metadata` to set a metadata that contains remote joins from remote schemas, and they would be enabled. Is this acceptable?
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3811
GitOrigin-RevId: a5b00f865cdb8890b0fc02b139c2ebd48929f138
### Description
This small PR improves the representation of an endpoint method from `Text` to an enum of the supported methods. Additionally, it cleans some of the instances defined on surrounding types (such as Postgres-specific instances on Endpoint types).
Due to a name conflict, this makes `RQL.Types.Endpoint` impossible to re-export from `RQL.Types`, which in turn forces several other modules to import it explicitly, which I think is fine since we want to ultimately get rid of `RQL.Types`.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3965
GitOrigin-RevId: 33869007d0d818ddf486fb61d1f6099f9dad7570
<!-- Thank you for ss in the Title above ^ -->
## Description ✍️
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<!-- Describe the changes from a user's perspective -->
Add some documentation on `ActionFieldG` type.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3945
GitOrigin-RevId: d9543ed7a8fe3ccfe9f5267c3a2ac71fb040f4db
### Description
This PR cleans `processRemoteJoins` by splitting the code, introducing comments, and applied the same strategies than #3810 did. Most importantly, it introduces a new module `RemoteJoin.Source`, made to be very similar to `RemoteJoin.RemoteSchema`, that exposes the required tooling to make a join call to a source, which decluters `Join`. Furthermore, this PR uses the same "dependency injection" to make the core of `Join` free from IO: this opens the door to testing the join engine in the unit tests.
None of the functions were modified when moved from their old module to the new one, but there's no way to easily see this in a diff.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3894
GitOrigin-RevId: 1e7c43006f092326e061f9ba12674e207b628bef
### Description
This PR moves Hasura-specific schema functions from `Hasura.GraphQL.Parser.Class` into `Hasura.GraphQL.Schema.Common`. It also removes the two corresponding monad aliases, and consequently harmonizes several parts of the code to use the same common constraint.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3947
GitOrigin-RevId: 40985a7d86da97a311bd480f9a57cc18c350c2a8
## Description
We go through the module `Hasura.Backends.MSSQL.FromIr` and split it into separate self-contained units, which we document.
Note that this PR has a slightly opinionated follow-up PR #3909 .
### Related Issues
Fix#3666
### Solution and Design
The module `FromIr` has given rise to:
* `FromIr.Expression`
* `FromIr.Query`
* `FromIr.Delete`
* `FromIr.Insert`
* `FromIr.Update`
* `FromIr.SelectIntoTempTable`
And `Execute.MutationResponse` has become `FromIr.MutationResponse` (after some slight adaptation of types).
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3908
GitOrigin-RevId: 364acf1bcdf74f2e19464c31cdded12bd8e9aa59
### Description
This PR improves the `Collect` module by re-ordering the functions to make clear what is public API and what is internal implementation. Furthermore, it makes use of `traverseOf` and `traverseFields` to reduce duplication. To do so, it also introduces a few more lenses in the rest of the codebase, and uses this opportunity to harmonize some structures that were not following our naming convention.
While the diff is massive, a lot of it is just code moving around; the file is now divided into separate sections:
- entry points: IR types for which we want to run the collection
- internal monadic structure
- internal traversals: functions that do nothing but drill down further
- actual transformations: the three cases where we do actually have work to do: selection sets on which we do want to insert join columns, extract remote relationships... those functions are left unchanged by this PR
- internal helpers
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3863
GitOrigin-RevId: f7cbecfae9eed9737b62acfa5848bfcf9d4651f6
### Description
#3810 was merged with comments still open; this small PR does a few minute clean-ups to address some remaining nits.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3941
GitOrigin-RevId: 3d15eb399828123640a73247b848bc4ddff02c38
### Description
This very small PR introduces `unionWithM`, to allow hashmap union that might fail, and uses it to transform an `error` into a `throw500`. It also reorders `HashMap.Strict.Extended` to group all "union" functions together.
There is, however, a broader question of whether we should encourage the proliferation of such functions. If so, we might also want to consider:
- `mapWithKeyM`, to remove the `unsafeMkName` of `RemoteJoin.Collect`
- `forWithKey`, as a flipped version of `traverseWithKey`
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3917
GitOrigin-RevId: a488d5bf04a73878b9e42f27ede36199bb4c920a
### Description
This PR adds the ability to perform remote joins from remote schemas in the engine. To do so, we alter the definition of an `ExecutionStep` targeting a remote schema: the `ExecStepRemote` constructor now expects a `Maybe RemoteJoins`. This new argument is used when processing the execution step, in the transport layer (either `Transport.HTTP` or `Transport.WebSocket`).
For this `Maybe RemoteJoins` to be extracted from a parsed query, this PR also extends the `Execute.RemoteJoin.Collect` module, to implement "collection" from a selection set. Not only do those new functions extract the remote joins, but they also apply all necessary transformations to the selection sets (such as inserting the necessary "phantom" fields used as join keys).
Finally in `Execute.RemoteJoin.Join`, we make two changes. First, we now always look for nested remote joins, regardless of whether the join we just performed went to a source or a remote schema; and second we adapt our join tree logic according to the special cases that were added to deal with remote server edge cases.
Additionally, this PR refactors / cleans / documents `Execute.RemoteJoin.RemoteServer`. This is not required as part of this change and could be moved to a separate PR if needed (a similar cleanup of `Join` is done independently in #3894). It also introduces a draft of a new documentation page for this project, that will be refined in the release PR that ships the feature (either #3069 or a copy of it).
While this PR extends the engine, it doesn't plug such relationships in the schema, meaning that, as of this PR, the new code paths in `Join` are technically unreachable. Adding the corresponding schema code and, ultimately, enabling the metadata API will be done in subsequent PRs.
### Keeping track of concrete type names
The main change this PR makes to the existing `Join` code is to handle a new reserved field we sometimes use when targeting remote servers: the `__hasura_internal_typename` field. In short, a GraphQL selection set can sometimes "branch" based on the concrete "runtime type" of the object on which the selection happens:
```graphql
query {
author(id: 53478) {
... on Writer {
name
articles {
title
}
}
... on Artist {
name
articles {
title
}
}
}
}
```
If both of those `articles` are remote joins, we need to be able, when we get the answer, to differentiate between the two different cases. We do this by asking for `__typename`, to be able to decide if we're in the `Writer` or the `Artist` branch of the query.
To avoid further processing / customization of results, we only insert this `__hasura_internal_typename: __typename` field in the query in the case of unions of interfaces AND if we have the guarantee that we will processing the request as part of the remote joins "folding": that is, if there's any remote join in this branch in the tree. Otherwise, we don't insert the field, and we leave that part of the response untouched.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3810
GitOrigin-RevId: 89aaf16274d68e26ad3730b80c2d2fdc2896b96c
…rmance
It makes sense to try to utilize multiple threads for metadata
operations since we expect them to come one at a time (and likely at
lower load periods anyway).
As noted, although we build roles in parallel now, the admin role is
still a bottleneck. For replace_metadata on huge_schema, on my machine
I get:
BEFORE: 22.7 sec
AFTER: 13.5 sec
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3911
GitOrigin-RevId: 4d4ee6ac8b5506603e70e4fc666a3aacc054d493
### Description
Several libraries define `catMaybes` as `mapMaybe id`. We had it defined in `Data.HashMap.Strict.Extended` already. This small PR also defines it in `Extended` modules for other containers and replaces every occurrence of `mapMaybe id` accordingly.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3884
GitOrigin-RevId: d222a2ca2f4eb9b725b20450a62a626d3886dbf4
In hasura/graphql-engine#5144, we noticed that having remote relationships in the schema is problematic for Relay. In particular, we don't support remote schemas in Relay at all, and because of this, remote relationships were also broken.
The fix was easy: when we're building the schema for Relay, whenever we encounter a remote relationship in our configuration, we simply skip building that field. The implementation was easy: (see hasura/graphql-engine#5145)
```diff
- SFRemoteRelationship info -> pure $ mkRemoteRelationshipFld info
+ SFRemoteRelationship info ->
+ -- https://github.com/hasura/graphql-engine/issues/5144
+ if isRelay then [] else pure $ mkRemoteRelationshipFld info
```
A test case was added in that PR to prevent us from accidentally re-including remote relationships in the Relay schema. (However, it now looks like that test case does not function correctly.)
The above code was later refactored in #3037, making use of the `MaybeT` effect. However, this effect was not used correctly, so that the result of the check was ignored.
This fixes the code to use the `MaybeT` effect correctly.
CC @0x777 @rakeshkky
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3868
GitOrigin-RevId: e528303e01eacf60173cba1eec1898986cf12359
### Description
There were several places in the codebase where we would either implement a generic container, or express the need for one. This PR extracts / creates all relevant containers, and adapts the relevant parts of the code to make use of said new generic containers. More specifically, it introduces the following modules:
- `Data.Set.Extended`, for new functions on `Data.Set`
- `Data.HashMap.Strict.Multi`, for hash maps that accept multiple values
- `Data.HashMap.Strict.NonEmpty`, for hash maps that can never be constructed as empty
- `Data.Trie`, for a generic implementation of a prefix tree
This PR makes use of those new containers in the following parts of the code:
- `Hasura.GraphQL.Execute.RemoteJoin.Types`
- `Hasura.RQL.Types.Endpoint*`
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3828
GitOrigin-RevId: e6c1b971bcb3f5ab66bc91d0fa4d0e9df7a0c6c6
The only purpose was enabling the developer API by default. I don't
think that justifies a flag and CPP usage.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3820
GitOrigin-RevId: 058c9a7b03e5e164ef88e35c42f50bae3c42b5b6
### Description
This PR is one further step towards remote joins from remote schemas. It introduces a custom partial AST to represent queries to remote schemas in the IR: we now need to augment what used to be a straightforward GraphQL AST with additional information for remote join fields.
This PR does the minimal amount of work to adjust the rest of the code accordingly, using `Void` in all places that expect a type representing remote relationships.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3794
GitOrigin-RevId: 33fc317731aace71f82ad158a1951ea93350d6cc
