@galaxy-stack/orbit-graphql-federation

Apollo Federation v2 support for distributed GraphQL.

Installation

bun add @galaxy-stack/orbit-graphql @galaxy-stack/orbit-graphql-federation

Features

• Federation v2 directives
• Subgraph schema generation
• Entity resolution
• External type extension
• Reference resolvers

Subgraph Setup

import { Module } from '@galaxy-stack/orbit-common';
import { GraphQLFederationModule } from '@galaxy-stack/orbit-graphql-federation';

@Module({
  imports: [
    GraphQLFederationModule.forRoot({
      autoSchemaFile: true,
    }),
  ],
})
export class UsersModule {}

Entity Definition

import { ObjectType, Field, Directive } from '@galaxy-stack/orbit-graphql';

@ObjectType()
@Directive('@key(fields: "id")')
export class User {
  @Field()
  id: number;

  @Field()
  name: string;
}

Reference Resolver

import { Resolver, ResolveReference } from '@galaxy-stack/orbit-graphql-federation';

@Resolver(() => User)
export class UsersResolver {
  @ResolveReference()
  resolveReference(ref: { id: number }) {
    return this.usersService.findById(ref.id);
  }
}

Extending External Types

@ObjectType()
@Directive('@extends')
@Directive('@key(fields: "id")')
export class User {
  @Field()
  @Directive('@external')
  id: number;

  @Field(() => [Post])
  posts: Post[];
}

Directives

Directive	Description
@key	Define entity primary key
@extends	Extend external type
@external	Mark field as external
@requires	Specify field dependencies
@provides	Declare provided fields