Controllers

Controllers in NestJS CRUD Automator are automatically generated based on your configuration. The @ApiController decorator transforms a simple controller class into a fully functional CRUD API with all necessary endpoints, DTOs, and Swagger documentation.

Basic Controller Setup

The minimal controller configuration requires only an entity and service:

user.controller.ts


import { Controller } from "@nestjs/common";
import { ApiController, EApiRouteType } from "@elsikora/nestjs-crud-automator";
import { UserEntity } from "./user.entity";
import { UserService } from "./user.service";
 
@Controller("users")
@ApiController<UserEntity>({
  entity: UserEntity,
  name: "Users",
  routes: {
    [EApiRouteType.CREATE]: {},
    [EApiRouteType.GET]: {},
    [EApiRouteType.GET_LIST]: {},
    [EApiRouteType.UPDATE]: {},
    [EApiRouteType.DELETE]: {},
  },
})
export class UserController {
  constructor(public service: UserService) {}
}

This generates the following endpoints:

POST /users - Create a new user
GET /users/:id - Get a user by ID
GET /users - Get a paginated list of users
PATCH /users/:id - Update a user
DELETE /users/:id - Delete a user

Route Configuration

Enabling and Disabling Routes

Control which routes are available:


@ApiController<UserEntity>({
  entity: UserEntity,
  name: "Users",
  routes: {
    [EApiRouteType.CREATE]: {},
    [EApiRouteType.GET]: {},
    [EApiRouteType.GET_LIST]: {},
    // UPDATE and DELETE routes are not configured, so they are disabled
  },
})

Or explicitly disable a route:


routes: {
  [EApiRouteType.DELETE]: {
    isEnabled: false,
  },
}

Custom Path

Override the default controller path:


@Controller("api/v1/users")
@ApiController<UserEntity>({
  entity: UserEntity,
  path: "api/v1/users", // Custom path
  name: "Users",
  routes: { /* ... */ },
})

Authentication and Authorization

Add authentication guards to specific routes:

user.controller.ts


import { JwtAuthGuard } from "../auth/guards/jwt-auth.guard";
 
@ApiController<UserEntity>({
  entity: UserEntity,
  name: "Users",
  routes: {
    [EApiRouteType.CREATE]: {
      authentication: {
        guard: JwtAuthGuard,
        bearerStrategies: ["jwt"],
      },
    },
    [EApiRouteType.UPDATE]: {
      authentication: {
        guard: JwtAuthGuard,
        bearerStrategies: ["jwt"],
      },
    },
    [EApiRouteType.DELETE]: {
      authentication: {
        guard: JwtAuthGuard,
        bearerStrategies: ["jwt"],
      },
    },
    [EApiRouteType.GET]: {}, // Public
    [EApiRouteType.GET_LIST]: {}, // Public
  },
})

Request Transformers

Automatically transform request data before processing:


import {
  EApiControllerRequestTransformerType,
  TRANSFORMER_VALUE_DTO_CONSTANT
} from "@elsikora/nestjs-crud-automator";
 
@ApiController<PostEntity>({
  entity: PostEntity,
  routes: {
    [EApiRouteType.CREATE]: {
      request: {
        transformers: {
          [EApiDtoType.BODY]: [
            {
              key: "authorId",
              type: EApiControllerRequestTransformerType.DYNAMIC,
              value: TRANSFORMER_VALUE_DTO_CONSTANT.AUTHORIZED_ENTITY,
              shouldSetValueEvenIfMissing: true,
            },
            {
              key: "createdAt",
              type: EApiControllerRequestTransformerType.STATIC,
              value: () => new Date(),
            },
          ],
        },
      },
    },
  },
})

Transformer types:

STATIC - Set a constant value
DYNAMIC - Extract value from request context (authenticated user, headers, IP)

Response Transformers

Transform response data before returning to client:


routes: {
  [EApiRouteType.GET]: {
    response: {
      transformers: [
        {
          key: "fullName",
          value: (entity) => `${entity.firstName} ${entity.lastName}`,
        },
      ],
    },
  },
}

Loading Relations

Configure automatic relation loading:


import { EApiControllerLoadRelationsStrategy } from "@elsikora/nestjs-crud-automator";
 
@ApiController<PostEntity>({
  entity: PostEntity,
  routes: {
    [EApiRouteType.GET]: {
      request: {
        relations: {
          shouldLoadRelations: true,
          relationsLoadStrategy: EApiControllerLoadRelationsStrategy.AUTO,
          servicesLoadStrategy: EApiControllerLoadRelationsStrategy.AUTO,
          relationsToLoad: ["author", "comments"],
        },
      },
      response: {
        relations: ["author", "comments"],
      },
    },
  },
})
export class PostController {
  constructor(
    public service: PostService,
    // Inject related services for loading
    public authorService: UserService,
    public commentsService: CommentService,
  ) {}
}

Strategies:

AUTO - Automatically detect and load relations
MANUAL - Explicitly specify which relations to load

Custom DTOs

Replace auto-generated DTOs with custom ones:


import { CreateUserDto } from "./dto/create-user.dto";
import { UpdateUserDto } from "./dto/update-user.dto";
import { UserResponseDto } from "./dto/user-response.dto";
 
@ApiController<UserEntity>({
  entity: UserEntity,
  routes: {
    [EApiRouteType.CREATE]: {
      dto: {
        body: CreateUserDto,
        response: UserResponseDto,
      },
    },
    [EApiRouteType.UPDATE]: {
      dto: {
        body: UpdateUserDto,
        response: UserResponseDto,
      },
    },
  },
})

Auto DTO Configuration

Customize auto-generated DTOs:


import {
  AllOrNoneOfListedPropertiesValidator
} from "@elsikora/nestjs-crud-automator";
 
@ApiController<UserEntity>({
  entity: UserEntity,
  routes: {
    [EApiRouteType.CREATE]: {
      autoDto: {
        [EApiDtoType.BODY]: {
          validators: [
            {
              constraintClass: AllOrNoneOfListedPropertiesValidator,
              options: ["firstName", "lastName"],
            },
          ],
        },
      },
    },
  },
})

Request Validation

Add custom request validators:


routes: {
  [EApiRouteType.CREATE]: {
    request: {
      validators: [
        {
          constraintClass: CustomValidator,
          options: ["field1", "field2"],
        },
      ],
    },
  },
}

Swagger Configuration

Customize Swagger documentation:


routes: {
  [EApiRouteType.CREATE]: {
    swagger: {
      summary: "Create a new user",
      description: "Creates a new user with the provided data",
      tags: ["Users", "Admin"],
    },
  },
}

Custom Decorators

Add additional decorators to routes:


import { UseInterceptors } from "@nestjs/common";
import { FileInterceptor } from "@nestjs/platform-express";
 
routes: {
  [EApiRouteType.CREATE]: {
    decorators: [
      UseInterceptors(FileInterceptor('avatar')),
    ],
  },
}

Observable Controllers

Enable subscriber hooks by marking the controller as observable:


import {
  ApiController,
  ApiControllerObservable
} from "@elsikora/nestjs-crud-automator";
 
@Controller("posts")
@ApiController({ /* ... */ })
@ApiControllerObservable()
export class PostController {
  constructor(public service: PostService) {}
}

Next Steps

Services - Configure service layer
DTOs - Understand DTO generation
Authentication - Implement auth guards
Subscriber System - Add hooks to intercept operations