@hazeljs/graphql

GraphQL server and client for HazelJS with decorator-based schema and typed client.

Installation

npm install @hazeljs/graphql @hazeljs/core

Server Usage

1. Define Object Types (optional, for complex return types)

import { ObjectType, Field } from '@hazeljs/graphql';

@ObjectType()
class User {
  @Field()
  id: string;

  @Field()
  name: string;
}

2. Create Resolvers

import { Injectable } from '@hazeljs/core';
import { Resolver, Query, Mutation, Arg } from '@hazeljs/graphql';

@Injectable()
@Resolver()
export class UserResolver {
  @Query()
  hello() {
    return 'Hello, GraphQL!';
  }

  @Query()
  user(@Arg('id') id: string) {
    return { id, name: 'John Doe' };
  }

  @Mutation()
  createUser(@Arg('name') name: string) {
    return { id: '1', name };
  }
}

3. Register GraphQL Module

import { HazelModule } from '@hazeljs/core';
import { GraphQLModule } from '@hazeljs/graphql';
import { UserResolver } from './user.resolver';

@HazelModule({
  imports: [
    GraphQLModule.forRoot({
      path: '/graphql',
      resolvers: [UserResolver],
    }),
  ],
})
export class AppModule {}

4. Start the App

import { HazelApp } from '@hazeljs/core';

const app = new HazelApp(AppModule);
app.listen(3000);
// GraphQL available at http://localhost:3000/graphql

Client Usage

import { GraphQLClient } from '@hazeljs/graphql';

const client = new GraphQLClient({
  url: 'http://localhost:3000/graphql',
});

// Query
const data = await client.query(`
  query {
    hello
    user(id: "1") { id name }
  }
`);

// Mutation
const result = await client.mutate(`
  mutation {
    createUser(name: "Alice") { id name }
  }
`);

Decorators Reference

Server

• @ObjectType(name?) - Mark class as GraphQL object type
• @Field(name?) - Mark property/method as field
• @Resolver(name?) - Mark class as resolver
• @Query(name?) - Mark method as Query field
• @Mutation(name?) - Mark method as Mutation field
• @Arg(name, type?) - Mark parameter as GraphQL argument

Client

• @GraphQLClientClass(url, headers?) - Mark class as GraphQL client
• @GraphQLQuery() - Mark method as query executor
• @GraphQLMutation() - Mark method as mutation executor