Import Fails to Import Interface of Union's Types Across Multiple Files

[tlivings]

Issue workflow progress

Progress of the issue based on the Contributor Workflow

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

~Note: I am reporting a bug but have not been able to reproduce in an isolated fashion yet.~ See https://github.com/tlivings/graphql-tools/tree/reproduce-5436 failing test.

Attempting to load schema using the GraphQLFileLoader and import statements.

Use case: A type's field is a union of types that implement interfaces.

Error: Unknown type "XXXX". Did you mean "XXXXXX", ...?
          at assertValidSDL (xxxx/node_modules/graphql/validation/validate.js:135:11)
          at buildASTSchema (xxxx/node_modules/graphql/utilities/buildASTSchema.js:44:34)
          at makeExecutableSchema (xxxx/node_modules/@graphql-tools/schema/cjs/makeExecutableSchema.js:73:47)
          at mergeSchemas (xxxx/node_modules/@graphql-tools/schema/cjs/merge-schemas.js:32:63)
          at getSchemaFromSources (xxxx/node_modules/@graphql-tools/load/cjs/schema.js:57:46)
          at loadSchema (xxxx/node_modules/@graphql-tools/load/cjs/schema.js:19:12)

To Reproduce Steps to reproduce the behavior:

See the failing test case for https://github.com/tlivings/graphql-tools/tree/reproduce-5436.

Expected behavior

Environment:

• @graphql-tools/load: 7.8.14

[tlivings]

Updated — I think I have a failing test for when using unions:

# schema
import U from 'u.graphql'

type A {
  field: U
}

# u.graphql

interface I {
  field3: String
}

type A {
  field1: String
}

type B implements I {
  field2: String
  field3: String
}

union U = A | B

If a nested union's type implements an interface that interface won't be imported...

[tlivings]

Here is a failing test: https://github.com/tlivings/graphql-tools/tree/reproduce-5436

[tlivings]

Hi @ardatan — is there anything additional I can provide? The way I reproduced was in the posted fork and then opening in codespaces and running the test.

I've also been trying to debug this but haven't found root cause yet. If you have any insight into the issue, I'd be happy to work on a PR!

[tlivings]

Updated the example in issue

[tlivings]

I have a potential fix I am trying out. It seems like addDefinition does not recursively try adding transitive dependencies.

[tlivings]

Basically:

 // Call addDefinition recursively to add all dependent documents
if ('name' in definition && definition.name) {
  const documentName = definition.name.value;
  const dependencyDefinitionForDocument = allImportedDefinitionsMap.get(documentName);
  dependencyDefinitionForDocument?.forEach(node => {
    if (node !== definition) {
      addDefinition(node, definitionName, definitionSet);
    }
});

For the test case's union, one of the types has an interface which will not be present in allImportedDefinitionsMap.get(documentName) and as a result, fail.

Only potentialTransitiveDefinitionsMap will contain the definitions it depends on.

[ardatan]

Thank you for all the details you've given so far. I tried to extract the tests from the commits in the branch you shared, but I couldn't. Could you please create a PR with this failing test?

[tlivings]

Done ☝️

[tlivings]

I've taken a stab at solving this issue within this code base: https://github.com/tlivings/graphql-import

It is indeed fixed, but likely doesn't support import the same way and is not typescript (which allows me easier manipulation of graphql ASTs etc).

I don't know if / when I will be able to see if I can apply something similar to the issue here though. I might simply offer it as an alternative graphql file loader for now (although currently it is unpublished).