我按照描述设置了 Nest.Js / TypeORM / MongoDB 堆栈here https://medium.com/@chnirt/how-do-i-practice-with-nestjs-nestjs-typeorm-mongodb-9e407818a296.
它可以使用以下方法在 MongoDB 中创建对象用户create()
函数中,该对象被记录到正确的数据库中User
收藏。
但是,当我尝试使用它来获取它时find({id})
or the findAll()
函数我收到错误,即使项目存在,我也无法从数据库中获取该项目。
这是我的user.service.ts
file:
import { Injectable, HttpException, HttpStatus } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { MongoRepository } from 'typeorm';
import { validate } from 'class-validator';
import { CreateUserDto } from './user.dto';
import { User } from '../model/user.entity';
import { UserRO } from './user.interface';
@Injectable()
export class UserService {
constructor(
@InjectRepository(User)
private readonly userRepository: MongoRepository<User>,
) {}
// abstracting access to the model via service
public async getAll() {
// getting data from database
return await this.userRepository.find();
}
// abstracting access to the model via service
public async get(id: string) {
const user = await this.userRepository.findOne({ _id: id });
if (!user) {
const errors = { User: ' not found' };
throw new HttpException({ errors }, 401);
}
return this.buildUserRO(user);
}
async create(dto: CreateUserDto): Promise<UserRO> {
// check uniqueness of username/email
const { username } = dto;
const newUser = new User();
newUser.username = username;
// newUser.contexts = [];
const errors = await validate(newUser);
if (errors.length > 0) {
const _errors = { username: 'Userinput is not valid.' };
throw new HttpException(
{ message: 'Input data validation failed', _errors },
HttpStatus.BAD_REQUEST,
);
} else {
const savedUser = await this.userRepository.save(newUser);
return this.buildUserRO(savedUser);
}
}
}
还有user.interface.ts
:
export interface UserData {
username: string;
_id: string;
}
// user response object
export interface UserRO {
user: UserData;
}
和一部分user.controller.ts
:
@Get(':id')
findOne(@Param('id') id: string): Promise<UserRO> {
console.log(`getting user with id: ${id}`);
const user = this.serv.get(id);
return user;
}
最后是model/user.entity.ts
:
@Entity({ name: 'User' })
export class User {
@ObjectIdColumn()
_id: string;
@Column({ type: 'varchar', length: 50 })
username: string;
@OneToMany((type) => Context, (context) => context.user)
contexts: Context[];
}
当我尝试查找保存的上下文时出现错误:
[Nest] 75671 - 09/22/2021, 9:22:18 PM ERROR [ExceptionsHandler] Cannot read property 'prototype' of undefined
TypeError: Cannot read property 'prototype' of undefined
at FindCursor.cursor.toArray (/Users/deemeetree/Documents/Root/benchmark-sql-graph/src/entity-manager/MongoEntityManager.ts:707:37)
at MongoEntityManager.<anonymous> (/Users/deemeetree/Documents/Root/benchmark-sql-graph/src/entity-manager/MongoEntityManager.ts:190:46)
at step (/Users/deemeetree/Documents/Root/benchmark-sql-graph/node_modules/typeorm/node_modules/tslib/tslib.js:143:27)
at Object.next (/Users/deemeetree/Documents/Root/benchmark-sql-graph/node_modules/typeorm/node_modules/tslib/tslib.js:124:57)
at fulfilled (/Users/deemeetree/Documents/Root/benchmark-sql-graph/node_modules/typeorm/node_modules/tslib/tslib.js:114:62)
at processTicksAndRejections (internal/process/task_queues.js:97:5)
我尝试使用 MongoDB 4. 和 3. 版本,也是同样的问题。
我做错了什么以及如何克服这个错误并能够在 MongoDB 中很好地查询记录?
Thanks!