Commit Graph

47 Commits

Author SHA1 Message Date
paritosh-08
fd30fb343b server: naming conventions for auto generated fields
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3982
Co-authored-by: Brandon Simmons <210815+jberryman@users.noreply.github.com>
GitOrigin-RevId: f90b2e8f394e7bd69780f003d2d980475f104f42
2022-05-26 11:55:29 +00:00
Rakesh Emmadi
acde210fdc server/bigquery: generate graphql schema for table computed fields
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4460
GitOrigin-RevId: 7b772cd9fba6b612ad05eb1aca1fa13e6ae8556d
2022-05-25 10:25:38 +00:00
Vamshi Surabhi
d5cb312f8b replace SQLOperator with ScalarSelectionArguments
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4426
GitOrigin-RevId: 69beda27ccf4cb47dab80d59ec383704be805bf6
2022-05-03 09:00:01 +00:00
Antoine Leblanc
3cbcbd9291 Remove RQL/Types.hs
## 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
2022-04-27 13:58:47 +00:00
Karthikeyan Chinnakonda
2325755954 server: streaming subscriptions schema generation and tests (incremental PR - 3)
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4259
Co-authored-by: Rikin Kachhia <54616969+rikinsk@users.noreply.github.com>
Co-authored-by: Brandon Simmons <210815+jberryman@users.noreply.github.com>
Co-authored-by: paritosh-08 <85472423+paritosh-08@users.noreply.github.com>
GitOrigin-RevId: 4d1b4ec3c01f3a839f4392d3b77950fc3ab30236
2022-04-22 19:54:11 +00:00
Philip Lykke Carlsen
df36cdac09 Refactor insert mutations IR use of "default values"
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4316
GitOrigin-RevId: 91f80902a2dc2a782821033f455c70c4e96f0950
2022-04-21 16:34:04 +00:00
Rakesh Emmadi
546f4994b6 server/gardening: rename IR insert mutation types
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4116
GitOrigin-RevId: ca3dd951dff7ee840eb3787900fcc32ada7d8879
2022-04-01 06:44:08 +00:00
Auke Booij
f026d44438 Role-invariant schema constructors
We build the GraphQL schema by combining building blocks such as `tableSelectionSet` and `columnParser`. These building blocks individually build `{InputFields,Field,}Parser` objects. Those object specify the valid GraphQL schema.

Since the GraphQL schema is role-dependent, at some point we need to know what fragment of the GraphQL schema a specific role is allowed to access, and this is stored in `{Sel,Upd,Ins,Del}PermInfo` objects.

We have passed around these permission objects as function arguments to the schema building blocks since we first started dealing with permissions during the PDV refactor - see hasura/graphql-engine@5168b99e46 in hasura/graphql-engine#4111. This means that, for instance, `tableSelectionSet` has as its type:
```haskell
tableSelectionSet ::
  forall b r m n.
  MonadBuildSchema b r m n =>
  SourceName ->
  TableInfo b ->
  SelPermInfo b ->
  m (Parser 'Output n (AnnotatedFields b))
```

There are three reasons to change this.

1. We often pass a `Maybe (xPermInfo b)` instead of a proper `xPermInfo b`, and it's not clear what the intended semantics of this is. Some potential improvements on the data types involved are discussed in issue hasura/graphql-engine-mono#3125.
2. In most cases we also already pass a `TableInfo b`, and together with the `MonadRole` that is usually also in scope, this means that we could look up the required permissions regardless: so passing the permissions explicitly undermines the "single source of truth" principle. Breaking this principle also makes the code more difficult to read.
3. We are working towards role-based parsers (see hasura/graphql-engine-mono#2711), where the `{InputFields,Field,}Parser` objects are constructed in a role-invariant way, so that we have a single object that can be used for all roles. In particular, this means that the schema building blocks _need_ to be constructed in a role-invariant way. While this PR doesn't accomplish that, it does reduce the amount of role-specific arguments being passed, thus fixing hasura/graphql-engine-mono#3068.

Concretely, this PR simply drops the `xPermInfo b` argument from almost all schema building blocks. Instead these objects are looked up from the `TableInfo b` as-needed. The resulting code is considerably simpler and shorter.

One way to interpret this change is as follows. Before this PR, we figured out permissions at the top-level in `Hasura.GraphQL.Schema`, passing down the obtained `xPermInfo` objects as required. After this PR, we have a bottom-up approach where the schema building blocks themselves decide whether they want to be included for a particular role.

So this moves some permission logic out of `Hasura.GraphQL.Schema`, which is very complex.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3608
GitOrigin-RevId: 51a744f34ec7d57bc8077667ae7f9cb9c4f6c962
2022-02-17 08:17:17 +00:00
Auke Booij
c4cdacf989 First attempt at deduplicating permission filters
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3362
Co-authored-by: Chris Parks <592078+cdparks@users.noreply.github.com>
GitOrigin-RevId: 802c099c26ff024e6cf594ea0317480e260486e9
2022-02-03 16:14:44 +00:00
Rakesh Emmadi
fbfdf9a04d server/mssql: restrict "count" aggregate query on multiple columns
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3354
GitOrigin-RevId: d9890782ff8e3ea40ec52c0da82e43ecf5c36d2b
2022-01-18 14:54:46 +00:00
Vamshi Surabhi
cca3831180 simplified schema cache representation of remote relationships
This PR pretty much does the same thing to remote relationship types in schemacache as what #2979 did to remote relationship types in the IR. On main remote relationships are represented by types of form `T from to`.  This PR changes it to `T from` which makes it a lot more reusable.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3037
GitOrigin-RevId: 90a5c9e2346c8dc2da6ec5b8c970d6c863d2afb8
2021-12-21 23:15:50 +00:00
Auke Booij
e805fc01f3 Avoid NonNullableType
This refactors the AST of GraphQL types so that we don't need `NonNullableType`.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3178
GitOrigin-RevId: 6513c8ea0a3cf4ad3ca7d8ef9ca996912fd5eedc
2021-12-20 17:03:28 +00:00
Philip Lykke Carlsen
2fbcd783e7 Refactor XOnConflict and ExtraInsertData
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/3055
GitOrigin-RevId: 06f7f92f0e09695f5f7bc02df457d3b96ac9f5f6
2021-12-09 09:06:56 +00:00
Vamshi Surabhi
23e1cb218a simplification of generalized joins execution
This PR simplifies the types that represent a remote relationship in IR so that they can be reused in other parts (in remote schema types) which could have remote relationships.

The comments on the PR explain the main changes.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2979
GitOrigin-RevId: 559c51d9d6ae79e2183ce4347018741b9096ac74
2021-12-07 13:12:57 +00:00
David Overton
5bfce057c6 Refactor remote schema customization
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2771
GitOrigin-RevId: 0c90136f956df3f4552140e6ca3d2f4766f8b3f5
2021-11-30 00:38:27 +00:00
Philip Lykke Carlsen
63ee663626 Excise query tags from backend schema
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2960
GitOrigin-RevId: ff6418609117abc8e0410c0897f2af9779cecf16
2021-11-25 21:08:54 +00:00
Philip Lykke Carlsen
984955d194 (Fix #2795) Add haddock documentation to schema generation and helpers
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2806
GitOrigin-RevId: 24005d471d469076f03390ca32442a6a3ebbce44
2021-11-10 00:38:40 +00:00
Philip Lykke Carlsen
3f8013abcb Fix #2741: Mechanically excise updateOperators from class BackendSchema
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2743
GitOrigin-RevId: c1e56bf66e5e0743e3c5b53a23a5b8a7d85ddf85
2021-11-08 18:13:16 +00:00
Brandon Simmons
b167120f96 server: add explicit export lists in OSS server and enforce with warning
We'll see if this improves compile times at all, but I think it's worth
doing as at least the most minimal form of module documentation.

This was accomplished by first compiling everything with
-ddump-minimal-imports, and then a bunch of scripting (with help from
ormolu)

**EDIT** it doesn't seem to improve CI compile times but the noise floor is high as it looks like we're not caching library dependencies anymore

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2730
GitOrigin-RevId: 667eb8de1e0f1af70420cbec90402922b8b84cb4
2021-11-04 16:09:38 +00:00
David Overton
aac64f2c81 Source typename customization (close graphql-engine#6974)
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/1616
GitOrigin-RevId: f7eefd2367929209aa77895ea585e96a99a78d47
2021-10-29 14:43:14 +00:00
Rakesh Emmadi
09ae6af337 server/mssql: insert SQL generation and execution
>

### Description
>
Insert mutations for MSSQL backend. This PR implements execution logic.

### Changelog

- [x] `CHANGELOG.md` is updated with user-facing content relevant to this PR. If no changelog is required, then add the `no-changelog-required` label.

### Affected components

- [x] Server
- [x] Tests

### Related Issues
->
Close https://github.com/hasura/graphql-engine-mono/issues/2114

### Steps to test and verify
>
Track a MSSQL table and perform the generated insert mutation to test.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2248
Co-authored-by: Abby Sassel <3883855+sassela@users.noreply.github.com>
Co-authored-by: Philip Lykke Carlsen <358550+plcplc@users.noreply.github.com>
GitOrigin-RevId: 936f138c80d7a928180e6e7b0c4da64ecc1f7ebc
2021-10-01 12:53:15 +00:00
Robert
11a454c2d6 server, pro: actually reformat the code-base using ormolu
This commit applies ormolu to the whole Haskell code base by running `make format`.

For in-flight branches, simply merging changes from `main` will result in merge conflicts.
To avoid this, update your branch using the following instructions. Replace `<format-commit>`
by the hash of *this* commit.

$ git checkout my-feature-branch
$ git merge <format-commit>^    # and resolve conflicts normally
$ make format
$ git commit -a -m "reformat with ormolu"
$ git merge -s ours post-ormolu

https://github.com/hasura/graphql-engine-mono/pull/2404

GitOrigin-RevId: 75049f5c12f430c615eafb4c6b8e83e371e01c8e
2021-09-23 22:57:37 +00:00
Naveen Naidu
3d95c67748 server/query-tags: implement new metadata specification and API
https://github.com/hasura/graphql-engine-mono/pull/2203

GitOrigin-RevId: 6169fcce0c6dccaec055bf8e723e9aa7c19a7f0c
2021-09-23 12:38:56 +00:00
Rakesh Emmadi
7ca48decfb server/mssql: integrate insert mutation schema parser for MSSQL backend
>

### Description
>
This PR is an incremental work towards [enabling insert mutations on MSSQL](https://github.com/hasura/graphql-engine-mono/pull/1974). In this PR, we generate insert mutation schema parser for MSSQL backend.

### Changelog

- [ ] `CHANGELOG.md` is updated with user-facing content relevant to this PR. If no changelog is required, then add the `no-changelog-required` label.

### Affected components

- [x] Server

https://github.com/hasura/graphql-engine-mono/pull/2141

GitOrigin-RevId: 8595008dece35f7fded9c52e134de8b97b64f53f
2021-08-31 13:35:49 +00:00
Auke Booij
7bead93827 server: remove remnants of query plan caching (fix #1795)
Query plan caching was introduced by - I believe - hasura/graphql-engine#1934 in order to reduce the query response latency. During the development of PDV in hasura/graphql-engine#4111, it was found out that the new architecture (for which query plan caching wasn't implemented) performed comparably to the pre-PDV architecture with caching. Hence, it was decided to leave query plan caching until some day in the future when it was deemed necessary.

Well, we're in the future now, and there still isn't a convincing argument for query plan caching. So the time has come to remove some references to query plan caching from the codebase. For the most part, any code being removed would probably not be very well suited to the post-PDV architecture of query execution, so arguably not much is lost.

Apart from simplifying the code, this PR will contribute towards making the GraphQL schema generation more modular, testable, and easier to profile. I'd like to eventually work towards a situation in which it's easy to generate a GraphQL schema parser *in isolation*, without being connected to a database, and then parse a GraphQL query *in isolation*, without even listening any HTTP port. It is important that both of these operations can be examined in detail, and in isolation, since they are two major performance bottlenecks, as well as phases where many important upcoming features hook into.

Implementation

The following have been removed:
- The entirety of `server/src-lib/Hasura/GraphQL/Execute/Plan.hs`
- The core phases of query parsing and execution no longer have any references to query plan caching. Note that this is not to be confused with query *response* caching, which is not affected by this PR. This includes removal of the types:
- - `Opaque`, which is replaced by a tuple. Note that the old implementation was broken and did not adequately hide the constructors.
- - `QueryReusability` (and the `markNotReusable` method). Notably, the implementation of the `ParseT` monad now consists of two, rather than three, monad transformers.
- Cache-related tests (in `server/src-test/Hasura/CacheBoundedSpec.hs`) have been removed .
- References to query plan caching in the documentation.
- The `planCacheOptions` in the `TenantConfig` type class was removed. However, during parsing, unrecognized fields in the YAML config get ignored, so this does not cause a breaking change. (Confirmed manually, as well as in consultation with @sordina.)
- The metrics no longer send cache hit/miss messages.

There are a few places in which one can still find references to query plan caching:

- We still accept the `--query-plan-cache-size` command-line option for backwards compatibility. The `HASURA_QUERY_PLAN_CACHE_SIZE` environment variable is not read.

https://github.com/hasura/graphql-engine-mono/pull/1815

GitOrigin-RevId: 17d92b254ec093c62a7dfeec478658ede0813eb7
2021-07-27 11:52:43 +00:00
Evie Ciobanu
4b0f5f09c9 server: add IR support for DB-to-DB joins
GJ IR changes cherry-picked from the original GJ branch. There is a separate (can be merged independently) PR for metadata changes (#1727) and there will be a different PR upcoming PR for execution changes.

https://github.com/hasura/graphql-engine-mono/pull/1810

Co-authored-by: Vamshi Surabhi <6562944+0x777@users.noreply.github.com>
GitOrigin-RevId: c31956af29dc9c9b75d002aba7d93c230697c5f4
2021-07-26 13:05:53 +00:00
Antoine Leblanc
8a77386fcf server: IR for DB-DB joins
### Description

This PR adds the required IR for DB to DB joins, based on @paf31 and @0x777 's `feature/db-to-db` branch.

To do so, it also refactors the IR to introduce a new type parameter, `r`, which is used to recursively constructs the `v` parameter of remote QueryDBs. When collecting remote joins, we replace `r` with `Const Void`, indicating at the type level that there cannot be any leftover remote join.

Furthermore, this PR refactors IR.Select for readability, moves some code from IR.Root to IR.Select to avoid having to deal with circular dependencies, and makes it compile by adding `error` in all new cases in the execution pipeline.

The diff doesn't make it clear, but most of Select.hs is actually unchanged. Declarations have just been reordered by topic, in the following order:
- type declarations
- instance declarations
- type aliases
- constructor functions
- traverse functions

https://github.com/hasura/graphql-engine-mono/pull/1580

Co-authored-by: Phil Freeman <630306+paf31@users.noreply.github.com>
GitOrigin-RevId: bbdcb4119cec8bb3fc32f1294f91b8dea0728721
2021-06-17 23:13:05 +00:00
Antoine Leblanc
9a8a211367 server: remove XDistinct, cleanup table arguments
https://github.com/hasura/graphql-engine-mono/pull/1028

GitOrigin-RevId: dae3d46097520f6838b7e95cdda1ab8d53dc9700
2021-06-15 15:54:12 +00:00
Vamshi Surabhi
e8e4f30dd6 server: support remote relationships on SQL Server and BigQuery (#1497)
Remote relationships are now supported on SQL Server and BigQuery. The major change though is the re-architecture of remote join execution logic. Prior to this PR, each backend is responsible for processing the remote relationships that are part of their AST.

This is not ideal as there is nothing specific about a remote join's execution that ties it to a backend. The only backend specific part is whether or not the specification of the remote relationship is valid (i.e, we'll need to validate whether the scalars are compatible).

The approach now changes to this:

1. Before delegating the AST to the backend, we traverse the AST, collect all the remote joins while modifying the AST to add necessary join fields where needed.

1. Once the remote joins are collected from the AST, the database call is made to fetch the response. The necessary data for the remote join(s) is collected from the database's response and one or more remote schema calls are constructed as necessary.

1. The remote schema calls are then executed and the data from the database and from the remote schemas is joined to produce the final response.

### Known issues

1. Ideally the traversal of the IR to collect remote joins should return an AST which does not include remote join fields. This operation can be type safe but isn't taken up as part of the PR.

1. There is a lot of code duplication between `Transport/HTTP.hs` and `Transport/Websocket.hs` which needs to be fixed ASAP. This too hasn't been taken up by this PR.

1. The type which represents the execution plan is only modified to handle our current remote joins and as such it will have to be changed to accommodate general remote joins.

1. Use of lenses would have reduced the boilerplate code to collect remote joins from the base AST.

1. The current remote join logic assumes that the join columns of a remote relationship appear with their names in the database response. This however is incorrect as they could be aliased. This can be taken up by anyone, I've left a comment in the code.

### Notes to the reviewers

I think it is best reviewed commit by commit.

1. The first one is very straight forward.

1. The second one refactors the remote join execution logic but other than moving things around, it doesn't change the user facing functionality.  This moves Postgres specific parts to `Backends/Postgres` module from `Execute`. Some IR related code to `Hasura.RQL.IR` module.  Simplifies various type class function signatures as a backend doesn't have to handle remote joins anymore

1. The third one fixes partial case matches that for some weird reason weren't shown as warnings before this refactor

1. The fourth one generalizes the validation logic of remote relationships and implements `scalarTypeGraphQLName` function on SQL Server and BigQuery which is used by the validation logic. This enables remote relationships on BigQuery and SQL Server.

https://github.com/hasura/graphql-engine-mono/pull/1497

GitOrigin-RevId: 77dd8eed326602b16e9a8496f52f46d22b795598
2021-06-11 03:27:39 +00:00
Antoine Leblanc
2d8ac777b3 server: introduce new custom scalars and remove offsetParser
GitOrigin-RevId: 5db058a7ae8f57bdc7e9844fcdd94e31ce11d961
2021-06-10 16:14:21 +00:00
Antoine Leblanc
8c3808f2bc server: make runMonadSchema backend agnostic
GitOrigin-RevId: ce4e36aedade18d47d035b90a69b9c545ea7d6ed
2021-06-09 13:03:08 +00:00
Karthikeyan Chinnakonda
9a99923fef server: support adding a tracked function as a computed field and vice versa
GitOrigin-RevId: 2f4db0b716d493ce245d9fa7e37e11382f18cd67
2021-05-20 06:29:24 +00:00
David Overton
ddad668f07 Fix/custom table name
GitOrigin-RevId: 5004717ac7d9e848ca186a1cdf52e375547034bf
2021-05-18 13:37:27 +00:00
Antoine Leblanc
2152911e24 server: introduce Hasura.Base (take 2)
GitOrigin-RevId: 0dd10f1ccd338b1cf382ebff59b6ee7f209d39a1
2021-05-11 15:19:33 +00:00
Antoine Leblanc
dd1192ca2c server: cleanup of language extensions [gardening]
GitOrigin-RevId: d862c724715cb8a4c2f37d2e0e525d12c46b18eb
2021-04-16 06:55:56 +00:00
Antoine Leblanc
1a4aad4ba1 server: introduce option to revert to v1 boolean collapse behaviour
GitOrigin-RevId: af6c944270301d8b17618a706ab328a28c0e51dc
2021-04-08 08:26:18 +00:00
Rakesh Emmadi
9ef603360c server: generalize schema cache building (#496)
Co-authored-by: Vamshi Surabhi <vamshi@hasura.io>
Co-authored-by: Vladimir Ciobanu <admin@cvlad.info>
Co-authored-by: Antoine Leblanc <antoine@hasura.io>
Co-authored-by: Stylish Haskell Bot <stylish-haskell@users.noreply.github.com>
GitOrigin-RevId: 9d631878037637f3ed2994b5d0525efd978f7b8f
2021-02-14 06:08:46 +00:00
Vladimir Ciobanu
6b7b68504a server: improve the UX around SourceInfo
GitOrigin-RevId: 47f7e9b7daa3f89771dd3883e9f6050274827e27
2021-02-08 16:31:17 +00:00
Antoine Leblanc
e449cf9990 server: finish generalizing mutations
GitOrigin-RevId: 645eefadee35f1642eee805e20161417ab38b949
2021-02-08 10:40:51 +00:00
Antoine Leblanc
83701fb63e server: changes to support other backends
GitOrigin-RevId: ec0ad47957ab6f9a0855623fffedb23924e7c75d
2021-02-03 16:25:17 +00:00
Antoine Leblanc
6494229f54 server: generalize functions (#393)
Co-authored-by: Vamshi Surabhi <0x777@users.noreply.github.com>
GitOrigin-RevId: 5d2140152a2a18601c785ea80a7689cbe3bd277e
2021-01-25 10:13:54 +00:00
Antoine Leblanc
4815fcd500 server: progress on generic metadata
This PR generalizes a bunch of metadata structures.

Most importantly, it changes `SourceCache` to hold existentially quantified values:
```
data BackendSourceInfo =
  forall b. Backend b => BackendSourceInfo (SourceInfo b)

type SourceCache = HashMap SourceName BackendSourceInfo
```

This changes a *lot* of things throughout the code. For now, all code using the schema cache explicitly casts sources to Postgres, meaning that if any non-Postgres `SourceInfo` makes it to the cache, it'll be ignored.

That means that after this PR is submitted, we can split work between two different aspects:
  - creating `SourceInfo` for other backends
  - handling those other sources down the line

GitOrigin-RevId: fb9ea00f32e840fc33c5467896fb1dfa5283ab42
2021-01-20 00:32:45 +00:00
hasura-bot
98ccd81704 Server: Remote relationships permissions
GITHUB_PR_NUMBER: 6125
GITHUB_PR_URL: https://github.com/hasura/graphql-engine/pull/6125

Co-authored-by: Karthikeyan Chinnakonda <15602904+codingkarthik@users.noreply.github.com>
GitOrigin-RevId: 53d0671e6335dad1af7cb00e3e05e7021a910673
2021-01-19 20:57:58 +00:00
Antoine Leblanc
0d194724ee server: generalize update schema
### Description

This PR updates the graphql schema to be backend-agnostic. To do so, it also moves the definition of operators to `BackendSchema`, to be specified differently per backend.

GitOrigin-RevId: 35b9d2d1bff93fb68b872d6ab0d3d12ec12c1b93
2021-01-08 19:46:34 +00:00
Rakesh Emmadi
29f2ddc289 server: support separate metadata database and server code setup for multi sources (#197)
This is an incremental PR towards https://github.com/hasura/graphql-engine/pull/5797

Co-authored-by: Anon Ray <ecthiender@users.noreply.github.com>
GitOrigin-RevId: a6cb8c239b2ff840a0095e78845f682af0e588a9
2020-12-28 12:56:55 +00:00
hasura-bot
115f2cb621 server: don't memoize backend scalar type reps through WithScalarType (#136)
Co-authored-by: Auke Booij <auke@hasura.io>
GITHUB_PR_NUMBER: 6281
GITHUB_PR_URL: https://github.com/hasura/graphql-engine/pull/6281
GitOrigin-RevId: b7ab3352af21175f0065f1bc2304a1232f6a5580
2020-12-03 12:22:24 +00:00
Auke Booij
3c3ed55914 server: schema that grows (#105)
This PR makes a bunch of schema generation code in Hasura.GraphQL.Schema backend-agnostic, by moving the backend-specific parts into a new BackendSchema type class. This way, the schema generation code can be reused for other backends, simply by implementing new instances of the BackendSchema type class.

This work is now in a state where the schema generators are sufficiently generic to accept the implementation of a new backend. That means that we can start exposing MS SQL schema. Execution is not implemented yet, of course.
The branch currently does not support computed fields or Relay. This is, in a sense, intentional: computed field support is normally baked into the schema generation (through the fieldSelection schema generator), and so this branch shows a programming technique that allows us to expose certain GraphQL schema depending on backend support. We can write support for computed fields and Relay at a later stage.

Co-authored-by: Antoine Leblanc <antoine@hasura.io>
GitOrigin-RevId: df369fc3d189cbda1b931d31678e9450a6601314
2020-12-01 15:51:13 +00:00