WIP: Integrate Federation Into Schema Builder

[shmulik-klein]

Initial PR for #521

[t1]

Sorry for not coming back to this earlier, I was on vacation. How far do you think you are? I'm just exploring the code a bit.

[shmulik-klein]

Sorry for not coming back to this earlier, I was on vacation. How far do you think you are? I'm just exploring the code a bit.

Sorry for the late reply.

Not too far, I was trying to replace the event listening on io/smallrye/graphql/federation/impl/Federation.java:111 into an explicit call to generate the federated schema before the schema is build on io/smallrye/graphql/bootstrap/Bootstrap.java:174.

[t1]

@shmulik-klein: the federation topic is getting more traction in my current project. Can you find some time to work on this in the near future? I completely understand how limited time is.

[robp94]

@t1 I added another pr at https://github.com/t1/graphql-federation-demo/pull/6.

There is still a problem left. On start up, there is a crash at https://github.com/smallrye/smallrye-graphql/blob/12ea1257a46c68c90851b59eaa53b92ce22340b2/server/federation/runtime/src/main/java/io/smallrye/graphql/federation/impl/Federation.java#L144 The problem is the line above https://github.com/smallrye/smallrye-graphql/blob/12ea1257a46c68c90851b59eaa53b92ce22340b2/server/federation/runtime/src/main/java/io/smallrye/graphql/federation/impl/Federation.java#L143 Without it, the war demo does work again. Do we need this for something, or could we remove it?

For Quarkus there is a second problem (maybe more). The Federation.class needs the jandex index. The index is created in the quarkus extension https://github.com/quarkusio/quarkus/blob/e24742a2f3da1572e7529dfd67b36f90abc7f704/extensions/smallrye-graphql/deployment/src/main/java/io/quarkus/smallrye/graphql/deployment/SmallRyeGraphQLProcessor.java#L209 and stored in the ScanningContext But when it is needed it is not there anymore since we have a different current. Do you maybe have an idea how to fix this, or who could have an idea?

[johgoe]

@robp94 Just an idea: if https://github.com/quarkusio/quarkus/issues/20802 is fixed

a configuration like

quarkus.smallrye-graphql.events.enabled=true
quarkus.smallrye-graphql.schema-include-scalars=true
quarkus.index-dependency.graphql-federation-runtime.group-id=io.smallrye
quarkus.index-dependency.graphql-federation-runtime.artifact-id=smallrye-graphql-federation-api
quarkus.index-dependency.graphql-federation-api.group-id=io.smallrye
quarkus.index-dependency.graphql-federation-api.artifact-id=smallrye-graphql-federation-api

and maven dependencies like

      <dependency>
        <groupId>io.smallrye</groupId>
        <artifactId>smallrye-graphql-federation-api</artifactId>
        <version>1.3.4</version>
      </dependency>
      <dependency>
        <groupId>io.smallrye</groupId>
        <artifactId>smallrye-graphql-federation-runtime</artifactId>
        <version>1.3.4</version>
      </dependency>

should fix the quarkus problems on startup.

[t1]

We discussed this in our regular MP GraphQL meeting. As we will merge the complete federation stuff into the core, some things will get much easier; we probably won't even need a federation specific Quarkus extension. I can't quite get my head around what this will look like, but @phillip-kruger might be better at describing what path we need to follow.

I'm also not sure how we can collaborate on this best, as @shmulik-klein doesn't seem to find the time to work on this, which is perfectly okay. But maybe we can bring this into a mergeable state, merge it and create a new PR. Or should we spawn a branch?

[johgoe]

In our project we got a working quarkus server with federation, with some technical tricks like working with a 2nd jandex index and manipulation of the schema in the federation gateway itself. Because of that we find some cases that hat not been working before in Smallrye Federation. I pushed this changes without the 2nd index to https://github.com/smallrye/smallrye-graphql/pull/1135 Maybe it can help.

[phillip-kruger]

@t1 - this looks more like what we need to do - update the model to contain info on federation, and use that info in Bootstrap

[robp94]

@jmartisk @phillip-kruger since federation is now supported I think this could be closed.