### Description
The main goal of this PR is, as stated, to remove the circular dependency in the schema building code. This cycle arises from the existence of remote relationships: when we build the schema for a source A, a remote relationship might force us to jump to the schema of a source B, or some remote schema. As a result, we end up having to do a dispatch from a "leaf" of the schema, similar to the one done at the root. In turn, this forces us to carry along in the schema a lot of information required for that dispatch, AND it forces us to import the instances in scope, creating an import loop.
As discussed in #4489, this PR implements the "dependency injection" solution: we pass to the schema a function to call to do the dispatch, and to get a generated field for a remote relationship. That way, this function can be chosen at the root level, and the leaves need not be aware of the overall context.
This PR grew a bit bigger than that, however; in an attempt to try and remove the `SourceCache` from the schema altogether, it changed a lot of functions across the schema building code, to thread along the `SourceInfo b` of the source being built. This avoids having to do cache lookups within a given source. A few cases remain, such as relay, that we might try to tackle in a subsequent PR.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4557
GitOrigin-RevId: 9388e48372877520a72a9fd1677005df9f7b2d72
### Description
There were several functions in `GraphQL.Schema.Common` that were unrelated to the schema building process, and were about metadata manipulation or dependency computation. Having those functions in the schema part of the code forces several places in the code to depend on the schema code, despite being completely unrelated.
This PR moves those functions where they make sense: alongside similar functions in `RQL.Types.*`, and rewrites `getRemoteDependencies` for clarity (it was using the term "indirect dependency" in a way that was inconsistent with the rest of the code).
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4568
GitOrigin-RevId: 948a18cebbb337a8bb6367c1f2d2ef5628209d96
By generalizing the instances, they can be written as attached instance derivations, rather than standalone ones.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4518
GitOrigin-RevId: 7a387911cf6ad46fe6acd36648275d6c2c68ffe3
A very minor cleanup (came out of documenting the architecture of actions). Does what's mentioned in the title.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4451
GitOrigin-RevId: d480ff438256df468df65b43d15f92a30b14b997
## Description
As the name suggests, `DML.Internal` contains internal implementation details of RQL's DML. However, a lot of unrelated parts of the codebase still use some of the code it contains. This PR fixes this, and removes all imports of `RQL.DML.Internal` from outside of `RQL.DML`. Most of the time, this involves moving a function out of `DML.Internal` to an underlying module (see `getRolePermInfo`) or moving a function _back_ into it (see `checkRetCols`).
This PR also clarifies a bit the situation with `withTyAnn` and `withTypeAnn` by renaming the former into `withScalarTypeAnn` and moving them together. Worth noting: there might be a bug lurking in that function, as it doesn't seem to use the proper type annotations for some extension types!
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4380
GitOrigin-RevId: c8ae5b4e8378fefc0bcccf778d97813df727d3cb
## Description
This PR removes `RQL.Types`, which was now only re-exporting a bunch of unrelated modules.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4363
GitOrigin-RevId: 894f29a19bff70b3dad8abc5d9858434d5065417
## Description
This small PR moves all functions in `RQL.Types.hs` to better locations. Most `askX` functions are moved alongside the `unsafe` functions they use. Several other functions are moved closer to their call site. `MetadataM` is moved alongside `Metadata`. This PR also documents the `ask` functions.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4355
GitOrigin-RevId: 0498a7e8f98e7a94af911dd375cad84ace7ddffa
### Description
Small PR that moves code out of `RQL.Types.hs`. Specifically, it moves `HasServerConfigCtx` to where `ServerConfigCtx` is defined. This removes code from `RQL.Types`, makes the dependency on `Server.Types` more explicit, and will make some further cleanups easier.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4336
GitOrigin-RevId: 95bb3467d741763892c4e68a38760497157ba1aa
In hasura/graphql-engine@7547786b2b, we made the logic that does a specific correctness check on the GraphQL schema runnable _post_-startup. However, in order to error out as early as possible, we explicitly do it on startup anyway.
Unfortunately a few instances of that logic were forgotten: until now we only executed it for non-relay authenticated GraphQL schemas.
This re-implements the "conflicting types" check for both the Relay schema, and for the unauthenticated schemas.
One key point where it does _not_ re-implement it is in `buildFullestDBSchema`, which is a very sketchy method that builds a GraphQL schema that is _only_ used internally in order to mark parts of the schema as inconsistent. There are two reasons I do not add the check here:
- This logic should get replaced entirely - see hasura/graphql-engine-mono#3882.
- Having conflicting types in `buildFullestDBSchema` does not imply there is actually a user-facing issue. The only "conflicting types" which are problematic are the ones which result in illegal _user-facing_ GraphQL schemas. `buildFullestDBSchema` is _never_ user-facing.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3885
GitOrigin-RevId: 49517dcbf51bcd97a3890514ec5e47499f770f32
`encJFromAssocList` is broken since it does not appropriately escape the keys of the JSON dictionaries. Presumably it should.
This is a hotfix for a JSON encoding issue. Longer-term solutions are being discussed in hasura/graphql-engine-mono#3736.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4139
GitOrigin-RevId: 27afff319d268a4ec017c8eafd694cc17c2fd7f0
### Motivation
While we strive to write clear code, we have historically struggled at Hasura with having very different styles and standards across the codebase. There's been efforts to standardize our coding style, we have an official styleguide that isn't maintained as closely as it should... We still have some work in front of us.
However, in the last ~year or so, there's been a huge push towards incrementally improving the situation. As part of this we've been blocking PRs that don't add enough comments, or don't improve the files that they touch.
While looking at `Hasura.GraphQL.Analyse`, it became apparent that this file did not meet the engineering standards that I would expect to see addressed during a code review. Some ways in which I think it falls short:
- lack of documentation
- no clear distinction between public / internal components
- "unidiomatic" Haskell code (such as using `Either Result Error`)
While there's no problem with a file looking like this during development, those issues should have been caught at review time. The fact that they weren't indicates a problem in our process that we will need to address: code quality and maintainability is paramount, and we all need to do our part.
### Description
This PR rewrites all of `Hasura.GraphQL.Analyze`, and adapts `Hasura.Server.OpenAPI` accordingly where needed. I've attempted to clarify names and add documentation based on my understanding of the code, and to clean what was unused (such as field variables). I don't think this PR is good enough as is, and I welcome criticism where I got my comments wrong / am happy to help y'all add more.
This PR makes one small change in the way error messages are reported (and adjusts the corresponding test accordingly); each error message is now prefixed with the path within the selection set:
```
⚠️ $.test.foo.bar.baz.mizpelled: field 'mizpelled' not found in object 'Baz'
```
### Note
This PR is currently **on top of #3962**. You can preview the changes in isolation by [diffing the branches](https://github.com/hasura/graphql-engine-mono/compare/nicuveo/clean-rest-endpoint-inconsistency-check..nicuveo/rewrite-analysis).
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3963
Co-authored-by: paritosh-08 <85472423+paritosh-08@users.noreply.github.com>
GitOrigin-RevId: 5ec38e0e753f0c12096a350db0737658495e2f15
### 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 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
### 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
<!-- Thank you for ss in the Title above ^ -->
## Description ✍️
<!-- Please fill this se-->
<!-- 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
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