nestjs+nodejs开发博客后端

安装nestjs
官方文档

npm i -g @nestjs/cli

新建项目

nest new nest-blog-api
Which package manager would you ❤️  to use? npm

修改运行端口

//main.ts
async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  await app.listen(5000);
// 运行端口
}

运行项目

//修改项目后自动重启
npm run start:dev
//或
npm run start

访问localhost:5000

查看nest命令

nest -h

生成模块

nest g mo posts

生成路由

nest g co posts

生成服务

nest g s posts

修改posts.module.ts

@Module({
  imports: [TypegooseModule.forFeature([Post])],
  controllers: [PostsController]
})
export class PostsModule {}

根据代码生成文档swagger
安装

npm install --save @nestjs/swagger swagger-ui-express

修改main.js

import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
...
 const options = new DocumentBuilder()
    .setTitle('Cats example')
    .setDescription('The cats API description')
    .setVersion('1.0')
    .addTag('cats')
    .build();
 const document = SwaggerModule.createDocument(app, options);
  SwaggerModule.setup('api', app, document);

连接数据库

npm i -s @typegoose/typegoose
npm i -s mongoose
npm i -s @types/mongoose

开启全局验证

npm i --save class-validator class-transformer
//main.ts
app.useGlobalPipes(new ValidationPipe())

使用
@IsNotEmpty({message:'请填写标题'})

使用typegoose减少耦合
npm install --save nestjs-typegoose
修改app.module.ts

@Module({
  imports: [
    TypegooseModule.forRoot("mongodb://localhost:27017/nest-blog-api", {
      useNewUrlParser: true
    }),
    PostsModule],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {}

修改posts.module.ts

@Module({
  imports: [TypegooseModule.forFeature([Post])],
  controllers: [PostsController]
})

自动在模型字段加上创建和更新时间

@modelOptions({
    schemaOptions:{
        timestamps:true,
    }
})
export class User {
    @ApiProperty({ example: '张三', description: '用户名' })
    @prop()
    username: string
    @ApiProperty({ example: '1234', description: '密码' })
    @prop()
    password: string
}

外键关联
model.ts

    @arrayProp({ itemsRef:'Episode'})
    episodes:Ref<Episode>[]

注册插件

@Module({
imports: [MongooseModule.forFeatureAsync([
{
name: 'Post',
useFactory: () => {
const schema = PostSchema;
schema.plugin(require('mongoose-paginate-v2'));
return schema;
}
}
])
],
controllers: [PostsController]
})
export class PostsModule { }

分页

    @Get()
    @ApiOperation({ summary: '显示博客列表' })
    async index(@Query('page') page: string = '1', @Query('limit') limit: string = '5') {
        let page_num = parseInt(page)
        let limit_num = parseInt(limit)
        let total = await this.postModel.count({})
        let data = await this.postModel.find({}, null, { skip: (page_num - 1) * limit_num, limit: limit_num })
        return { total: total, data: data }
    }

注意不加await将导致Converting circular structure to JSON错误

npm i --save @nestjs/config