NestJS GraphQL: Getting Started

What you get

Drop @relayerjs/nestjs-graphql into a NestJS project and get a complete code-first GraphQL API:

• Full CRUD - queries (list, findById, count, aggregate) and mutations (create, update, delete)
• Auto-generated types - ObjectType, WhereInput, OrderByInput, CreateInput, UpdateInput, Connection, Edge, PageInfo
• Three pagination modes - flat cursor (default), offset, or Relay-style cursor with edges
• Rich filtering - per-type operators, AND/OR/NOT combinators, relation filters (some/every/none)
• Ordering - multi-field sorting, nested relation ordering
• Aggregation - groupBy, count, sum, avg, min, max
• Selection optimization - only fetches fields the client actually requested
• Lifecycle hooks - beforeCreate, afterFind, etc.
• Typed context - extract request data and use it for row-level scoping

All type-safe, all configurable.

Installation

npm install @relayerjs/nestjs-graphql @relayerjs/core @relayerjs/drizzle @relayerjs/nestjs-common

Assumes a working NestJS GraphQL setup (@nestjs/graphql, @nestjs/apollo, graphql, graphql-scalars).

Quick start

1. Define your entity

entities/post.entity.ts

import { createRelayerEntity } from '@relayerjs/drizzle';

import * as schema from '../schema';

export class PostEntity extends createRelayerEntity(schema, 'posts') {}

Need computed fields? Extend the class:

const UserBase = createRelayerEntity(schema, 'users');

export class UserEntity extends UserBase {
  @UserBase.computed({
    resolve: ({ table, sql }) => sql`${table.firstName} || ' ' || ${table.lastName}`,
  })
  fullName!: string;
}

2. Create an entity map

entities/entity-map.ts

export const entities = { users: UserEntity, posts: PostEntity };
export type EM = typeof entities;

3. Register the module

app.module.ts

import { RelayerGraphqlModule } from '@relayerjs/nestjs-graphql';

@Module({
  imports: [
    RelayerGraphqlModule.forRoot({
      db,
      schema,
      entities: [UserEntity, PostEntity],
      defaultRelationLimit: 50,
    }),
    UsersModule,
    PostsModule,
  ],
})
export class AppModule {}

4. Create a service

@Injectable()
export class UsersService extends RelayerService<UserEntity, EM> {
  constructor(@InjectRelayer() r: RelayerInstance<EM>) {
    super(r, UserEntity);
  }
}

5. Create a resolver

import { GqlResolver, RelayerResolver } from '@relayerjs/nestjs-graphql';

@GqlResolver(UserEntity, { name: 'User' })
export class UsersResolver extends RelayerResolver<UserEntity, EM> {
  constructor(usersService: UsersService) {
    super(usersService);
  }
}

That’s it. One decorator, full GraphQL CRUD:

Type	Name	Description
Query	users	Cursor-paginated list
Query	user(id: ID!)	Find by ID
Query	usersCount(where: ...)	Count matching records
Query	usersAggregate(...)	Aggregation with groupBy
Mutation	createUser(data: ...)	Create one
Mutation	updateUser(id: ID!, ...)	Update one
Mutation	deleteUser(id: ID!)	Delete one

All GraphQL types are generated automatically: User, UserWhereInput, UserOrderByInput, CreateUserInput, UpdateUserInput, UserCursorResult, PageInfo, UserAggregate, plus scalar filter inputs.

What’s next

For the full API reference (resolver configuration, pagination modes, filtering operators, hooks, typed context, field selection), see the @relayerjs/nestjs-graphql README.