【nestjs】一般学习路线
nestjs中文文档
其实几个月前也对nestjs进行了学习,前前后后看了很多文档、博客,另外也找了相应的代码看了,但最后也还是一知半解,只是知道大概怎么写,怎么用。
这次下定决心再次看一遍,从代码学习到文档又梳理了一遍,总算是有点眉目,把心得分享一下。
一、首先找一个开源代码,尝试跑起来并深度阅读,打console了解和熟悉每个模块、每一步的具体功能。
我这边参考了nest-admin
按照作者的逻辑,安装MySql 、Redis 环境,将db/kapok.sql导入sql中,运行就可以。
作为一个前端要按照后端思维去理解nest,显然有些困难,因此细致的注释和console是很必要的。
二、如果你对工程已经熟悉了,那么第二步就是去阅读中文文档,这次一定要细致的阅读,并从文档中找到程序中的类比。
三、紧接着就是对工程进行模块新增了,参考其他模块我写了一个test模块。
总得来说,一个增删改查的页面会包含 dto、entities、controller、service、module。
entities:包含了当前功能的字段类型、表设计。
dto:包含了service中接口要使用的具体参数定义,明确了各个参数的限制类型,swigger等。
service:取dto中的文件信息用在相应的方法中,用于接收参数并利用typeOrm进行数据库具体方法的处理。
controller:使用Service中的方法,定义了各种get、post、delete、put等接口调用。
module: 承载service、entities、controller,最终作为统一出口文件,让根文件(app.module.ts)去引用。
// test.entity.ts
import { Entity, PrimaryGeneratedColumn, Column, CreateDateColumn } from 'typeorm'
import { ApiProperty } from '@nestjs/swagger'
import { $enum } from 'ts-enum-util'import { StatusValue } from '../../../common/enums/common.enum'@Entity('sys_post1')
export class TestEntity {@ApiProperty({ description: 'id' })@PrimaryGeneratedColumn({ type: 'bigint' })id: string@ApiProperty({ description: '岗位编码' })@Column({ type: 'varchar', length: 50, comment: '岗位编码' })code: string@ApiProperty({ description: '岗位名称' })@Column({ type: 'varchar', length: 50, comment: '岗位名称' })name: string@ApiProperty({ description: '状态', enum: $enum(StatusValue).getValues() })@Column({ type: 'tinyint', default: StatusValue.NORMAL, comment: '岗位状态,1-有效,0-禁用' })status: StatusValue@ApiProperty({ description: '备注' })@Column({ type: 'text',default: null, comment: '备注' })remark: string@ApiProperty({ description: '排序' })@Column({ name: 'order_num', type: 'int', comment: '排序', default: 0 })orderNum: number@ApiProperty({ description: '创建时间' })@CreateDateColumn({ type: 'timestamp', name: 'create_date', comment: '创建时间' })createDate: Date
}
// create-test.dto.ts
import { ApiProperty } from '@nestjs/swagger'
import { IsString, IsNotEmpty, IsNumber, Min, IsOptional, MinLength, MaxLength } from 'class-validator'export class CreateTestDto {@ApiProperty({ description: '岗位编码' })@IsString({ message: 'code 类型错误,正确类型 string' })@IsNotEmpty({ message: 'code 不能为空' })@MaxLength(50, { message: '岗位编码最多50个字符' })readonly code: string@ApiProperty({ description: '岗位名称' })@IsString({ message: 'name 类型错误, 正确类型 string' })@IsNotEmpty({ message: 'name 不能为空' })@MinLength(2, { message: '岗位名称至少2个字符' })@MaxLength(50, { message: '岗位名称最多50个字符' })readonly name: string@ApiProperty({ description: '排序' })@IsNumber({}, { message: 'orderNum 类型错误, 正确类型 number ' })@Min(0)readonly orderNum: number@ApiProperty({ description: '备注' })@IsString({ message: 'remark 类型错误, 正确类型 string' })@IsOptional()readonly remark: string
}
// test.service.ts
import { Injectable } from '@nestjs/common'
import { InjectRepository, InjectEntityManager } from '@nestjs/typeorm'
import { Repository, Like, EntityManager } from 'typeorm'
import { plainToInstance } from 'class-transformer'import { ResultData } from '../../common/utils/result'
import { AppHttpCode } from '../../common/enums/code.enum'import { TestEntity } from './entities/test.entity'import { FindTestListDto } from './dto/findTestList.dto'
import { CreateTestDto } from './dto/create-test.dto'
import { UpdateTestDto } from './dto/update-test.dto'@Injectable()
export class TestService {constructor(@InjectRepository(TestEntity)private readonly postRepo: Repository<TestEntity>,@InjectEntityManager()private readonly postManager: EntityManager,) {}/** 创建岗位 */async create(dto: CreateTestDto): Promise<ResultData> {const existing = await this.postRepo.findOne({ where: { code: dto.code, name: dto.name } })if (existing) return ResultData.fail(AppHttpCode.POST_REPEAT, '当前岗位名称与编码已存在,请修改后重新创建')const post = plainToInstance(TestEntity, dto)const res = await this.postManager.transaction(async (transactionalEntityManager) => {return await transactionalEntityManager.save<TestEntity>(post)})if (!res) ResultData.fail(AppHttpCode.SERVICE_ERROR, '创建失败,请稍后重试')return ResultData.ok(res)}/** 更新岗位 */async update(dto: UpdateTestDto): Promise<ResultData> {const existing = await this.postRepo.findOne({ where: { id: dto.id } })if (!existing) return ResultData.fail(AppHttpCode.POST_NOT_FOUND, '岗位不存在或已被删除,请修改后重新添加')const { affected } = await this.postManager.transaction(async (transactionalEntityManager) => {return await transactionalEntityManager.update<TestEntity>(TestEntity, dto.id, dto)})if (!affected) return ResultData.fail(AppHttpCode.SERVICE_ERROR, '更新失败,请稍后尝试')return ResultData.ok()}/** 删除岗位 */async delete(id: string): Promise<ResultData> {const existing = await this.postRepo.findOne({ where: { id } })if (!existing) return ResultData.fail(AppHttpCode.POST_NOT_FOUND, '岗位不存在或已被删除')const { affected } = await this.postManager.transaction(async (transactionalEntityManager) => {return await transactionalEntityManager.delete<TestEntity>(TestEntity, id)})if (!affected) return ResultData.fail(AppHttpCode.SERVICE_ERROR, '删除部门失败,请稍后尝试')return ResultData.ok()}/** 查询岗位 */async findList(dto: FindTestListDto): Promise<ResultData> {const { size, page, name, code, status } = dtoconst where = {...(!!name ? { name: Like(`%${name}%`) } : null),...(!!code ? { code: Like(`%${code}%`) } : null),...(![null, undefined].includes(status) ? { status } : null),}const posts = await this.postRepo.findAndCount({where,order: { orderNum: 'DESC', id: 'DESC', createDate: 'DESC' },skip: size * (page - 1),take: size,})return ResultData.ok({ list: posts[0], total: posts[1] })}/** 查询单个岗位信息 */async findOne(id: string): Promise<ResultData> {const post = await this.postRepo.findOne({ where: { id } })return ResultData.ok(post)}
}
// test.controller.ts
import { Controller, Post, Body, Delete, Get, Put, Param, Query } from '@nestjs/common'
import { ApiOperation, ApiTags, ApiBearerAuth } from '@nestjs/swagger'import { ApiResult } from '../../common/decorators/api-result.decorator'
import { ResultData } from '../../common/utils/result'import { TestEntity } from './entities/test.entity'
import { TestService } from './test.service'import { FindTestListDto } from './dto/findTestList.dto'
import { CreateTestDto } from './dto/create-test.dto'
import { UpdateTestDto } from './dto/update-test.dto'@ApiTags('岗位模块')
@ApiBearerAuth()
@Controller('test')
export class TestController {constructor(private readonly testService: TestService) {}@Post()@ApiOperation({ summary: '创建岗位' })@ApiResult(TestEntity)async create(@Body() dto: CreateTestDto): Promise<ResultData> {return this.testService.create(dto)}@Put()@ApiOperation({ summary: '岗位更新' })@ApiResult()async update(@Body() dto: UpdateTestDto): Promise<ResultData> {return this.testService.update(dto)}@Get('list')@ApiOperation({ summary: '查询岗位列表' })@ApiResult(TestEntity, true)async find(@Query() dto: FindTestListDto): Promise<ResultData> {return this.testService.findList(dto)}@Get(':id')@ApiOperation({ summary: '查询岗位详情' })@ApiResult(TestEntity)async findOne(@Param('id') id: string): Promise<ResultData> {return this.testService.findOne(id)}@Delete(':id')@ApiOperation({ summary: '删除岗位' })@ApiResult()async delete(@Param('id') id: string): Promise<ResultData> {return this.testService.delete(id)}
}
// test.module.ts
import { Module } from '@nestjs/common'
import { TypeOrmModule } from '@nestjs/typeorm'import { TestEntity } from './entities/test.entity'
import { TestService } from './test.service'
import { TestController } from './test.controller'@Module({imports: [TypeOrmModule.forFeature([TestEntity])],providers: [TestService],controllers: [TestController]
})
export class TestModule {}
写在后面的话:
前端学习后端思维绝非易事,一定要脚踏实地,不可心浮气躁。
后面想再出一个更细的nestjs模块解释,欢迎关注。