Unable to lint federation v2 schemas in v4 graphql-eslint

[InsidersByte]

Issue workflow progress

Progress of the issue based on the Contributor Workflow

• [ ] 1. The issue provides a reproduction available on GitHub, Stackblitz or CodeSandbox

  For example, you can start off by editing the 'basic' example on Stackblitz.

  Please make sure the graphql-eslint version under package.json matches yours.

• [ ] 2. A failing test has been provided

• [ ] 3. A local solution has been provided

• [ ] 4. A pull request is pending review

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Describe the bug

When attempting to lint a federation v2 schema with v4 of graphql-eslint that includes a federation directive e.g. @key. It fails with the error below.

Parsing error: Error while loading schema: Unknown directive "@key".

Unknown directive "@link".

It was possible to lint with v3 of graphql-eslint by setting parserOptions.schemaOptions.assumeValid to true, but it doesn't seem possible to do this in v4.

To Reproduce Steps to reproduce the behavior:

You can see an example failing schema here on the playground.

Expected behavior

To be able to lint federation v2 schemas.

Environment:

• @graphql-eslint/eslint-plugin: 4.2.1

Additional context

I did see both of the following and while they are related it might not be the only way to resolve this issue hence I raised another one. Feel free to close if you think its appropriate:

• https://github.com/dimaMachina/graphql-eslint/issues/1824
• https://github.com/dimaMachina/graphql-eslint/pull/2049

[dimaMachina]

try 4.3.0-alpha-20241204113935-074a093b359d2947f263679eac8596958876a3b6

graphql-eslint should parse federation subgraphs without parse errors and you could even use known-directives rule which previously reported errors about unknown @link directive.

But for linting federation subgraphs schemas optional peer dependency @apollo/subgraph should be installed (you'll get runtime error in case of missing it)

[InsidersByte]

I just tried it and it worked great!

Thanks