graphql-engine/server
Antoine Leblanc 5920134dcb Decouple Analyse and OpenAPI from remote schema introspection and internal execution details.
### 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
2022-03-22 07:37:49 +00:00
..
bench-wrk server, pro: actually reformat the code-base using ormolu 2021-09-23 22:57:37 +00:00
benchmarks ci: hide old benchmark reports for PRs with many comments 2022-02-24 20:09:17 +00:00
documentation server/tests: unify HASURA_BIGQUERY_SERVICE_KEY and HASURA_BIGQUERY_SERVICE_ACCOUNT env vars 2022-03-14 07:50:35 +00:00
packaging ci: add support for linux/arm64 docker image 2021-12-09 09:34:22 +00:00
src-exec Yeet some default-extensions 2022-03-16 00:40:17 +00:00
src-lib Decouple Analyse and OpenAPI from remote schema introspection and internal execution details. 2022-03-22 07:37:49 +00:00
src-rsr ci: tag release v2.3.1 and v2.4.0-beta.2 2022-03-17 07:44:42 +00:00
src-test Yeet some default-extensions 2022-03-16 00:40:17 +00:00
tests/integration Yeet some default-extensions 2022-03-16 00:40:17 +00:00
tests-hspec server: refactor the term "live query" to "subscription" 2022-03-21 10:40:49 +00:00
tests-py (Fix #8267) Handle subscriptions in MSSQL when results exceed 2048 characters 2022-03-21 12:16:14 +00:00
.dockerignore update packages (#251) 2018-08-08 13:10:13 +05:30
.gitignore server/citus: feature branch 2021-05-21 02:47:51 +00:00
commit_diff.txt Rewrite GraphQL schema generation and query parsing (close #2801) (#4111) 2020-08-21 12:27:01 -05:00
COMPILING-ON-M1.md update contributing and compiling on m1 2022-01-21 11:21:49 +00:00
CONTRIBUTING.md server/gardening: move local hoogle setup from Makefile to bash script 2022-03-16 10:44:01 +00:00
graphql-engine.cabal Decouple Analyse and OpenAPI from remote schema introspection and internal execution details. 2022-03-22 07:37:49 +00:00
Makefile ci: misc. cleanup, naming 2022-01-03 06:26:39 +00:00
STYLE.md server, CI: use ormolu as a formatter for Haskell sources 2021-09-23 21:23:21 +00:00
testing-guidelines.md server: testing guidelines 2022-03-08 09:53:27 +00:00