Apollo Federation not working

[mengqing]

Bug report

Describe the bug

After enabling federation option, Federation service definition is not being generated

Expected behavior

It should return the federation service definition

Screenshots

If applicable, add screenshots to help explain your problem.

Code snippets

// path: ./config/plugins.js

module.exports = {
  //
  graphql: {
    config: {
      endpoint: '/graphql',
      shadowCRUD: true,
      playgroundAlways: false,
      depthLimit: 7,
      amountLimit: 100,
      federation: true,
      apolloServer: {
        tracing: false,
      },
    },
  },
};

query __ApolloGetServiceDefinition__ {
  _service {
    sdl
  }
}

{
  "errors": [
    {
      "message": "Cannot query field \"_service\" on type \"Query\".",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "extensions": {
        "code": "GRAPHQL_VALIDATION_FAILED",
        "exception": {
          "stacktrace": [
            "GraphQLError: Cannot query field \"_service\" on type \"Query\"."
          ]
        }
      }
    }
  ]
}

System

• Node.js version: v16.13.0
• NPM version: 8.3.0
• Strapi version: v4
• Database: postgres
• Operating system:

Additional context

Add any other context about the problem here.

[mengqing]

It seems that this PR #6146 from v3 does not exist in v4. Does anyone know the reason for that?

[derrickmehaffy]

@Convly I'm honestly not sure here, can you share any information. I only see that we have the apollo federation package installed but it's not referenced anywhere in the code-base:

strapi/packages/plugins/graphql/package.json

Line 30 in b1df5a6

"@apollo/federation": "^0.28.0",

I assume we plan to add federation support at some point in the future but I don't believe it's been built in yet, just like subscriptions. We were only preparing for it.

---

@mengqing in v4 we completely rewrote the entire graphql plugin from the ground up so we didn't get the chance to rebuild all of the v3 features. Time constraints

[Convly]

@derrickmehaffy It's exactly that. We plan to add it when we'll have enough bandwidth, but we had to make compromises to release the V4 GQL plugin. Both federation & aggregates queries have been cut out of the release but will be implemented sooner or later.

[derrickmehaffy]

@derrickmehaffy It's exactly that. We plan to add it when we'll have enough bandwidth, but we had to make compromises to release the V4 GQL plugin. Both federation & aggregates queries have been cut out of the release but will be implemented sooner or later.

Cool, that's what I thought. Thanks for the clarification JS 🙏

[mengqing]

@derrickmehaffy @Convly Thanks for clearing this up for me. For now, I had to use a third-party plugin to transform the schema into a federated specification.

[derrickmehaffy]

Hey all, we are currently moving many feature requests to our new feedback and feature request website to help clean up the GitHub issues and make it easier for us to review bug reports and fix them.

I have moved this feature to the following URL: https://feedback.strapi.io/developer-experience/p/add-graphql-federation-v4
If you are interested in this feature please feel free to go there and add more comments and/or upvote it there.

For now I will close this and lock it so that all new information goes into our new feedback website.
Thanks!

[kentnek]

@derrickmehaffy @Convly Thanks for clearing this up for me. For now, I had to use a third-party plugin to transform the schema into a federated specification.

Hi @mengqing, may I know which plugin you used to add federation and how to integrate it with strapi? Thanks!

[mengqing]

@kentnek I use graphql-transform-federation to transform the strapi schema into a federated spec

[kentnek]

@kentnek I use graphql-transform-federation to transform the strapi schema into a federated spec

Hi @mengqing, I also found that transform plugin but I'm not sure how to add that to my existing Strapi instance. Do you add it as a Strapi extension? Any code example would be greatly appreciated!

[mengqing]

I basically followed this blog to achieve what I needed

[kentnek]

@mengqing Thank you for the link. I tried to use it in my project but got this error while running:

Cannot find module '@apollo/federation/dist/types'
Error: Cannot find module '@apollo/federation/dist/types'
Require stack:
- ...\node_modules\graphql-transform-federation\dist\transform-federation.js

It looks like the transform plugin needs GraphQL 15 and below:

graphql-transform-federation@2.2.0" has incorrect peer dependency "graphql@^14.0.0 || ^15.0.0".

My project is using GraphQL 16.5.0. May I ask if you encounter the same issue?

[Jeff-Tian]

@mengqing Thank you for the link. I tried to use it in my project but got this error while running:

Cannot find module '@apollo/federation/dist/types'
Error: Cannot find module '@apollo/federation/dist/types'
Require stack:
- ...\node_modules\graphql-transform-federation\dist\transform-federation.js

It looks like the transform plugin needs GraphQL 15 and below:

graphql-transform-federation@2.2.0" has incorrect peer dependency "graphql@^14.0.0 || ^15.0.0".

My project is using GraphQL 16.5.0. May I ask if you encounter the same issue?

I met the exact same issue. I tried troubleshooting the problem using graphql-transform-federation but to no avail. In the end, I decided to fork it and made some changes before publishing it to @jeff-tian/graphql-transform-federation. This new version resolved the issue for me, and I hope it helps others who encountered the same problem.