NestJS+TypeORM+PostgreSQL报错：找不到TasksRepository元数据

问题描述 #

尝试为实体创建仓库用于PostgreSQL数据库操作时，持续抛出以下错误：

[Nest] 32358 ERROR [ExceptionsHandler] No metadata for "TasksRepository" was found.

测试控制器接口时返回500内部服务器错误，相关代码如下：

相关代码 #

tasks.module.ts #

import { Module } from '@nestjs/common';
import { TasksController } from './tasks.controller';
import { TasksService } from './tasks.service';
import { TypeOrmModule } from '@nestjs/typeorm';
import { TasksRepository } from './tasks.repository';

@Module({
  imports: [TypeOrmModule.forFeature([TasksRepository])],
  controllers: [TasksController],
  providers: [TasksService]
})
export class TasksModule {}

tasks.repository.ts #

import { EntityRepository, Repository } from "typeorm";
import { Task } from "./tasks.entity";

@EntityRepository(Task)
export class TasksRepository extends Repository<Task> {
    
}

tasks.service.ts #

import { Injectable, NotFoundException } from '@nestjs/common';
import { TaskStatus } from './tasks.enum';
import { CreateTaskDto } from 'src/dto/tasks/create-task.dto';
import { TasksRepository } from './tasks.repository';
import { InjectRepository } from '@nestjs/typeorm';
import { Task } from './tasks.entity';

@Injectable()
export class TasksService {
    constructor(
        @InjectRepository(TasksRepository)
        private tasksRepository: TasksRepository,
    ) {}

    async getTaskById(id: string): Promise<Task> {
        const task = await this.tasksRepository.findOne({where: {id}});
        if (!task) {
            throw new NotFoundException;
        }
        return task;
    }

    async createTask(createTaskDto: CreateTaskDto): Promise<Task> {
        const { title, description } = createTaskDto;
        const task = this.tasksRepository.create({
            title,
            description,
            status: TaskStatus.OPEN,
        });

        await this.tasksRepository.save(task);
        return task;
    }
}

tasks.controller.ts #

import { Controller, Get, Param, Post, Body } from '@nestjs/common';
import { TasksService } from './tasks.service';
import { Task } from './tasks.entity';
import { CreateTaskDto } from 'src/dto/tasks/create-task.dto';

@Controller('tasks')
export class TasksController {
    constructor(private tasksService: TasksService) {}

    @Get('/:id')
    getTaskById(@Param('id') id: string): Promise<Task> { 
        return this.tasksService.getTaskById(id);
    }

    @Post()
    createTask(@Body() createTaskDto: CreateTaskDto): Promise<Task> {
        return this.tasksService.createTask(createTaskDto);
    }
}

app.module.ts #

import { Module } from '@nestjs/common';
import { TasksModule } from './modules/tasks/tasks.module';
import { TypeOrmModule } from '@nestjs/typeorm';

@Module({
  imports: [
    TasksModule,
    TypeOrmModule.forRoot({
      type: 'postgres',
      host: 'localhost',
      port: 5432,
      username: 'postgres',
      password: 'postgres',
      database: 'task-management',
      autoLoadEntities: true,
      synchronize: true,
    }),
  ],
})
export class AppModule {}

解决办法 #

核心原因 #

TypeORM的@EntityRepository装饰器已被废弃，NestJS与TypeORM的集成逻辑不再支持通过该方式注册自定义仓库，导致元数据无法被识别。

方案一：适配新版本的自定义仓库 #

1. 修改tasks.repository.ts
   移除@EntityRepository，改用@Injectable并通过DataSource初始化仓库：

import { Injectable, Repository, DataSource } from "@nestjs/typeorm";
import { Task } from "./tasks.entity";

@Injectable()
export class TasksRepository extends Repository<Task> {
  constructor(private dataSource: DataSource) {
    super(Task, dataSource.createEntityManager());
  }
}

2. 更新tasks.module.ts
   注册Task实体而非仓库，并将TasksRepository加入providers：

import { Module } from '@nestjs/common';
import { TasksController } from './tasks.controller';
import { TasksService } from './tasks.service';
import { TypeOrmModule } from '@nestjs/typeorm';
import { TasksRepository } from './tasks.repository';
import { Task } from './tasks.entity';

@Module({
  imports: [TypeOrmModule.forFeature([Task])],
  controllers: [TasksController],
  providers: [TasksService, TasksRepository]
})
export class TasksModule {}

3. tasks.service.ts无需修改
   原有的@InjectRepository(TasksRepository)注入方式依然有效。

方案二：直接使用实体仓库（无需自定义仓库） #

如果不需要在仓库中添加自定义方法，可以简化实现：

1. 删除tasks.repository.ts
2. 修改tasks.service.ts
   直接注入Task实体对应的仓库：

import { Injectable, NotFoundException } from '@nestjs/common';
import { TaskStatus } from './tasks.enum';
import { CreateTaskDto } from 'src/dto/tasks/create-task.dto';
import { InjectRepository } from '@nestjs/typeorm';
import { Task } from './tasks.entity';
import { Repository } from 'typeorm';

@Injectable()
export class TasksService {
    constructor(
        @InjectRepository(Task)
        private tasksRepository: Repository<Task>,
    ) {}

    // 其余代码保持不变
}

3. 更新tasks.module.ts
   仅注册Task实体：

import { Module } from '@nestjs/common';
import { TasksController } from './tasks.controller';
import { TasksService } from './tasks.service';
import { TypeOrmModule } from '@nestjs/typeorm';
import { Task } from './tasks.entity';

@Module({
  imports: [TypeOrmModule.forFeature([Task])],
  controllers: [TasksController],
  providers: [TasksService]
})
export class TasksModule {}

额外检查 #

确保Task实体正确使用@Entity()装饰器，示例如下：

import { Entity, Column, PrimaryGeneratedColumn } from 'typeorm';
import { TaskStatus } from './tasks.enum';

@Entity()
export class Task {
  @PrimaryGeneratedColumn('uuid')
  id: string;

  @Column()
  title: string;

  @Column()
  description: string;

  @Column({
    type: 'enum',
    enum: TaskStatus,
    default: TaskStatus.OPEN,
  })
  status: TaskStatus;
}

内容的提问来源于stack exchange，提问作者motionless570