$ npm i -g @nestjs/cli

$ nest new memberManage

member-manage/src
      ├ app.controller.spec.ts
      ├ app.controller.ts
      ├ app.module.ts
      ├ app.service.ts
      └ main.ts

$ cd ./member-manage/
$ nest generate resource members

member-manage/src/members
      ├ dto/
      │   ├ create-member.dto.ts
      │   └ update-member.dto.ts
      ├ entities/
      │   └ member.entity.ts
      ├ members.controller.spec.ts
      ├ members.controller.ts
      ├ members.module.ts
      ├ members.service.spec.ts
      └ members.service.ts

$ npm start

$ npm install --save @nestjs/swagger

  import { NestFactory } from '@nestjs/core';
+ import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
  import { AppModule } from './app.module';

  async function bootstrap() {
    const app = await NestFactory.create(AppModule);

+   const config = new DocumentBuilder().build();
+   const document = SwaggerModule.createDocument(app, config);
+   SwaggerModule.setup('api', app, document);

    await app.listen(3000);
}
bootstrap();

export declare function ApiTags(...tags: string[]): MethodDecorator & ClassDecorator;

import {
  Controller,
  Get,
  Post,
  Body,
  Patch,
  Param,
  Delete,
} from '@nestjs/common';
  import { MembersService } from './members.service';
  import { CreateMemberDto } from './dto/create-member.dto';
  import { UpdateMemberDto } from './dto/update-member.dto';
+ import { ApiTags } from '@nestjs/swagger';

  @Controller('members')
+ @ApiTags('/members')
  export class MembersController {
    constructor(private readonly membersService: MembersService) {}

    @Post()
    create(@Body() createMemberDto: CreateMemberDto) {
      return this.membersService.create(createMemberDto);
    }

    @Get()
    findAll() {
     return this.membersService.findAll();
    }

    @Get(':id')
    findOne(@Param('id') id: string) {
      return this.membersService.findOne(+id);
    }

    @Patch(':id')
    update(@Param('id') id: string, @Body() updateMemberDto: UpdateMemberDto) {
      return this.membersService.update(+id, updateMemberDto);
    }

    @Delete(':id')
    remove(@Param('id') id: string) {
      return this.membersService.remove(+id);
    }
  }

import { NestFactory } from '@nestjs/core';
import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);

-  const config = new DocumentBuilder().build();
+  const config = new DocumentBuilder()
+   .setTitle('Members API docs')
+   .setDescription('MembersのAPI仕様書です。')
+   .setVersion('1.0')
+   .build();
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api', app, document);

  await app.listen(3000);
}
bootstrap();

  import { Controller, Get, Post, Body, Patch, Param, Delete } from '@nestjs/common';
  import { MembersService } from './members.service';
  import { CreateMemberDto } from './dto/create-member.dto';
  import { UpdateMemberDto } from './dto/update-member.dto';
- import { ApiTags } from '@nestjs/swagger';
+ import { ApiTags, ApiProduces, ApiOperation, ApiParam, ApiResponse } from '@nestjs/swagger';
+ import { Member } from './entities/member.entity';

  @Controller('members')
  @ApiTags('/members')
  export class MembersController {
   constructor(private readonly membersService: MembersService) {}
 
  @Post()
+ @ApiProduces('application/json; charset=utf-8')
+ @ApiOperation({ summary: '単体登録API' })
+ @ApiResponse({
+   status: 201,
+   description: '登録したメンバー設定を返却',
+   type: Member,
+ })
  create(@Body() createMemberDto: CreateMemberDto) {
     return this.membersService.create(createMemberDto);
   }

  @Get()
+ @ApiProduces('application/json; charset=utf-8')
+ @ApiOperation({ summary: '全体取得API' })
+ @ApiResponse({
+   status: 200,
+   description: '登録済メンバー設定を複数返却',
+   type: Member,
+ })
   findAll() {
     return this.membersService.findAll();
   }
 
  @Get(':id')
+ @ApiProduces('application/json; charset=utf-8')
+ @ApiOperation({ summary: '単体取得API' })
+ @ApiParam({
+   name: 'id',
+   type: Number,
+   example: 1,
+ })
+ @ApiResponse({
+   status: 200,
+   description: '指定されたIDのメンバー設定を返却',
+   type: Member,
+ })
  findOne(@Param('id') id: string) {
    return this.membersService.findOne(+id);
  }

  @Patch(':id')
+ @ApiProduces('application/json; charset=utf-8')
+ @ApiOperation({ summary: '単体更新API' })
+ @ApiParam({
+   name: 'id',
+   type: Number,
+   example: 1,
+ })
+ @ApiResponse({
+   status: 200,
+   description: '更新後のメンバー設定を返却',
+   type: Member,
+ })
  update(@Param('id') id: string, @Body() updateMemberDto: UpdateMemberDto) {
    return this.membersService.update(+id, updateMemberDto);
  }

  @Delete(':id')
+ @ApiProduces('application/json; charset=utf-8')
+ @ApiOperation({ summary: '単体削除API' })
+ @ApiParam({
+   name: 'id',
+   type: Number,
+   example: 1,
+ })
+ @ApiResponse({
+   status: 200,
+   description: '削除されたメンバーの設定を返却',
+   type: Member,
+ })
  remove(@Param('id') id: string) {
    return this.membersService.remove(+id);
  }
 }

+ import { ApiProperty } from '@nestjs/swagger';

  export class Member {
+   @ApiProperty({ example: 1, description: 'メンバーID' })
+   id: number;

+  @ApiProperty({ example: 'アルファ太郎', description: 'メンバーの氏名' })
+   name: string;

+  @ApiProperty({ example: 25, description: 'メンバーの年齢' })
+   age: number;
}

import { NestFactory } from '@nestjs/core';
import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
import { AppModule } from './app.module';
+import * as path from 'path';
+import { writeFileSync } from 'fs';
+import { dump } from 'js-yaml';

 async function bootstrap() {
   const app = await NestFactory.create(AppModule);

   const config = new DocumentBuilder()
     .setTitle('Members API docs')
     .setDescription('MembersのAPI仕様書です。')
     .setVersion('1.0')
     .build();
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api', app, document);
+  const outputPath = path.resolve(process.cwd(), 'openapi.yml');
+  writeFileSync(outputPath, dump(document, {}));

  await app.listen(3000);
}
bootstrap();

$ npm install -g dredd

$ dredd init
? Location of the API description document (openapi.yml) (node:16336) Warning: Accessing non-existent property 'padLevels' of module exports inside circular dependency
(Use `node --trace-warnings ...` to show where the warning was created)
? Location of the API description document openapi.yml   
? Command to start the API server under test npm start
? Host of the API under test http://localhost:3000/
? Do you want to use hooks to customize Dredd's behavior? Yes
? Programming language of the hooks JavaScript
? Do you want to report your tests to the Apiary inspector? Yes
? Enter Apiary API key (leave empty for anonymous, disposable test reports)
? Dredd is best served with Continuous Integration. Do you want to create CI configuration? No

$ dredd

> member-manage@0.0.1 start
> nest start

[Nest] 17760  - 2022/12/23 15:03:14     LOG [NestFactory] Starting Nest application...
[Nest] 17760  - 2022/12/23 15:03:14     LOG [InstanceLoader] AppModule dependencies initialized +25ms
[Nest] 17760  - 2022/12/23 15:03:14     LOG [InstanceLoader] MembersModule dependencies initialized +0ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RoutesResolver] AppController {/}: +4981ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/, GET} route +2ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RoutesResolver] MembersController {/members}: +1ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/members, POST} route +2ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/members, GET} route +1ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/members/:id, GET} route +1ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/members/:id, PATCH} route +1ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [RouterExplorer] Mapped {/members/:id, DELETE} route +2ms
[Nest] 17760  - 2022/12/23 15:03:19     LOG [NestApplication] Nest application successfully started +3ms

pass: GET (200) / duration: 53ms
fail: POST (201) /members duration: 30ms
fail: GET (200) /members duration: 9ms
fail: GET (200) /members/1 duration: 9ms
fail: PATCH (200) /members/1 duration: 8ms
fail: DELETE (200) /members/1 duration: 8ms

  //返却値のcontent-typeがtext/htmlである
  findOne(id: number) {
    return `This action returns a #${id} member`;
  }

 import { Injectable } from '@nestjs/common';
 import { CreateMemberDto } from './dto/create-member.dto';
 import { UpdateMemberDto } from './dto/update-member.dto';
+import { promises } from 'fs';
+const { readFile } = promises;

@Injectable()
export class MembersService {
  create(createMemberDto: CreateMemberDto) {
    return 'This action adds a new member';
  }

  findAll() {
    return `This action returns all members`;
  }

- findOne(id: number) {
+ async findOne(id: number) {
-    return `This action returns a #${id} member`;
+    const contents = await readFile('src/members/members.json', 'utf-8');
+    const json = JSON.parse(contents);
+    let tmp = null;
+
+    json.members.forEach((member: { id: number }) => {
+      if (member.id == id) {
+        tmp = member;
+      }
+    });
+    return tmp;
  }

    update(id: number, updateMemberDto: UpdateMemberDto) {
    return `This action updates a #${id} member`;
  }

  remove(id: number) {
    return `This action removes a #${id} member`;
  }
}

 {
     "members": [
       { "id": 1, "name": "テスト次郎" },
       { "id": 2, "name": "テック三郎" },
       { "id": 3, "name": "ブログ四郎" }
     ]
 }

info: Displaying failed tests...
fail: GET (200) /members/1 duration: 66ms
fail: body: At '/age' Missing required property: age

{
    "members": [
      { "id": 1, "name": "テスト次郎", "age": 30 },
      { "id": 2, "name": "テック三郎", "age": 28 },
      { "id": 3, "name": "ブログ四郎", "age": 26 }
    ]
}

pass: GET (200) /members/1 duration: 124ms
complete: 2 passing, 4 failing, 0 errors, 0 skipped, 6 total
complete: Tests took 12110ms