NestJs Mongoose保存文档触发ValidationError：必填字段缺失

错误详情 #

ValidationError: Problem validation failed: creator: Path `creator` is required., description: Path `description` is required., title: Path `title` is required.

相关代码与请求信息 #

Schema定义 #

import { Prop, Schema, SchemaFactory } from '@nestjs/mongoose';
import { HydratedDocument } from 'mongoose';

export type ProblemDocument = HydratedDocument<Problem>;

@Schema()
export class Problem {
  @Prop({ required: true })
  title: string;

  @Prop({ required: true })
  description: string;

  @Prop({ required: true })
  creator: string;

  @Prop()
  ideas: string[];

  @Prop()
  createdAt: Date;

  @Prop()
  updatedAt: Date;

  @Prop()
  deletedAt: Date;
}

export const ProblemSchema = SchemaFactory.createForClass(Problem);

Problems服务create方法 #

async create(createProblemDto: CreateProblemDto): Promise<any> {
    try {
      console.log(createProblemDto);
      const problem = new this.ProblemModel({ createProblemDto });
      return problem.save();
    } catch (error) {
      throw error;
    }
  }

CreateProblemDto定义 #

import { IsString, IsNotEmpty } from 'class-validator';

export class CreateProblemDto {
  @IsString({ message: 'Title must be a string' })
  @IsNotEmpty({ message: 'Title is required' })
  title: string;

  @IsString({ message: 'Description must be a string' })
  @IsNotEmpty({ message: 'Description is required' })
  description: string;

  @IsString({ message: 'Creator must be a string' })
  @IsNotEmpty({ message: 'Creator is required' })
  creator: string;
}

请求信息 #

POST http://localhost:3000/problems
Content-Type: application/json

{
"title": "hello",
"description": "world",
"creator": "john_doe"
}

控制台日志 #

{
  createProblemDto: { title: 'hello', description: 'world', creator: 'john_doe' }
}
[Nest] 17591  - 01/02/2024, 6:00:27 PM   ERROR [RpcExceptionsHandler] Problem validation failed: creator: Path `creator` is required., description: Path `description` is required., title: Path `title` is required.
ValidationError: Problem validation failed: creator: Path `creator` is required., description: Path `description` is required., title: Path `title` is required.
    at model.Document.invalidate (/home/arta/project/vsCode/nestjs/devProblem/problems/node_modules/.pnpm/mongoose@8.0.3/node_modules/mongoose/lib/document.js:3187:32)
    at /home/arta/project/vsCode/nestjs/devProblem/problems/node_modules/.pnpm/mongoose@8.0.3/node_modules/mongoose/lib/document.js:2980:17
    at /home/arta/project/vsCode/nestjs/devProblem/problems/node_modules/.pnpm/mongoose@8.0.3/node_modules/mongoose/lib/schemaType.js:1368:9
    at processTicksAndRejections (node:internal/process/task_queues:77:11)

解决方案 #

问题出在创建Mongoose模型实例时的参数传递错误：

// 错误写法：将createProblemDto作为嵌套对象传入
const problem = new this.ProblemModel({ createProblemDto });

// 正确写法：直接传入createProblemDto，或者展开对象
const problem = new this.ProblemModel(createProblemDto);
// 或者
const problem = new this.ProblemModel({ ...createProblemDto });

原因说明 #

控制台日志显示，createProblemDto被包裹在一个同名的键下，导致Mongoose无法找到Schema中定义的顶层title、description、creator字段，因此触发必填字段的验证失败。直接传入对象（或展开对象）可以确保字段正确映射到Schema定义的路径上。

内容的提问来源于stack exchange，提问作者arta