[aws-appsync] Code first object type implementation of multiple interfaces generates invalid graphql output

Using the code-first strategy: when an ObjectType implements several InterfaceType, the generated schema produces a syntax error since the interfaces are appended via , instead of &.

Reproduction Steps

Given the following code:

const myInterface1 = new InterfaceType('MyInterface1', {
  definition: {
    // ...
  }
});

const myInterface2 = new InterfaceType('MyInterface2', {
  definition: {
    // ...
  }
});

const myObjectType = new ObjectType('MyObjectType', {
  interfaceTypes: [myInterface1, myInterface2],
  // ...
});

What did you expect to happen?

Output should be

interface MyInterface1 {
  # ...
}

interface MyInterface2 {
  # ...
}

type MyObjectType implements MyInterface1 & MyInterface2 {
  # ...
}

What actually happened?

Instead the code outputs the following, which is invalid graphql code:

interface MyInterface1 {
  # ...
}

interface MyInterface2 {
  # ...
}

type MyObjectType implements MyInterface1, MyInterface2 {
  # ...
}

Environment

• CLI Version :
• Framework Version: 1.63.0
• Node.js Version:
• OS :
• Language (Version):

Other

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This is 🐛 Bug Report

[chargome]

@BryanPan342 So far it has helped me a lot writing my (rather complex) GraphQL schema in a more modular and clear way. The only thing I am missing is the final schema output somewhere in my project, is there a straightforward way to do this? Good work!

[BryanPan342]

@chargome glad to hear you have been having a good experience so far 😊

The only thing I am missing is the final schema output somewhere in my project, is there a straightforward way to do this?

check out this sample app i made!

It’s not complete with functional resolvers at the moment, but I added a bit of code to cdk-app.ts to spit out the generated schema 😃

https://github.com/BryanPan342/starwars-code-first/blob/master/bin/starwars-code-first.ts#L7-L20