feat(learning): 完成NestJS核心概念和自定义提供者的学习

- 引入并配置了Fastify替代Express作为HTTP服务器，提高应用性能。
- 实现了PostController及其CRUD操作，包括请求方法和参数处理。
- 创建并使用CreatePostDto和UpdatePostDto进行请求数据验证。
- 完成了多种自定义提供者的实现和应用，如值提供者、类提供者和工厂提供者。
- 添加了一些全局类型定义，如RecordAny和BaseType，用于增强代码的可读性和健壮性。
- 通过ConfigService添加和管理新的环境配置项。

src/app.module.ts

@@ -1,10 +1,21 @@
 import { Module } from '@nestjs/common';
 
-import { WelcomeController } from '@/modules/welcome/welcome.controller';
+import { ContentModule } from '@/modules/content/content.module';
+import { WelcomeModule } from '@/modules/welcome/welcome.module';
+
+import { CoreModule } from './modules/core/core.module';
 
 @Module({
-    imports: [],
-    controllers: [WelcomeController],
+    imports: [
+        ContentModule,
+        WelcomeModule,
+        CoreModule.forRoot({
+            config: {
+                name: '欢迎访问 Ink NestJS API !',
+            },
+        }),
+    ],
+    controllers: [],
     providers: [],
 })
 export class AppModule {}

src/modules/content/content.module.ts

@@ -0,0 +1,11 @@
+import { Module } from '@nestjs/common';
+
+import { PostController } from './controllers';
+import { PostService } from './services';
+
+@Module({
+    controllers: [PostController],
+    providers: [PostService],
+    exports: [PostService],
+})
+export class ContentModule {}

src/modules/content/controllers/index.ts

@@ -0,0 +1 @@
+export * from './post.controller';

src/modules/content/controllers/post.controller.ts

@@ -0,0 +1,60 @@
+import { Body, Controller, Delete, Get, Param, Patch, Post, ValidationPipe } from '@nestjs/common';
+
+import { CreatePostDto, UpdatePostDto } from '../dtos';
+import { PostService } from '../services';
+
+/**
+ * 文章控制器
+ * 负责处理与文章相关的请求，如获取文章列表、创建新文章等。
+ */
+@Controller('post')
+export class PostController {
+    constructor(private postService: PostService) {}
+
+    @Get()
+    async index() {
+        return this.postService.findAll();
+    }
+
+    @Get(':id')
+    async show(@Param('id') id: number) {
+        return this.postService.findOne(id);
+    }
+
+    @Post()
+    async store(
+        @Body(
+            new ValidationPipe({
+                transform: true,
+                forbidNonWhitelisted: true,
+                forbidUnknownValues: true,
+                validationError: { target: false },
+                groups: ['create'],
+            }),
+        )
+        data: CreatePostDto,
+    ) {
+        return this.postService.create(data);
+    }
+
+    @Patch()
+    async update(
+        @Body(
+            new ValidationPipe({
+                transform: true,
+                forbidNonWhitelisted: true,
+                forbidUnknownValues: true,
+                validationError: { target: false },
+                groups: ['update'],
+            }),
+        )
+        data: UpdatePostDto,
+    ) {
+        return this.postService.update(data);
+    }
+
+    @Delete(':id')
+    async delete(@Param('id') id: number) {
+        return this.postService.delete(id);
+    }
+}

src/modules/content/dtos/create-post.dto.ts

@@ -0,0 +1,24 @@
+import { Injectable } from '@nestjs/common';
+import { IsNotEmpty, IsOptional, MaxLength } from 'class-validator';
+
+@Injectable()
+export class CreatePostDto {
+    @MaxLength(255, {
+        always: true,
+        message: '帖子标题长度最大为$constraint1',
+    })
+    @IsNotEmpty({ groups: ['create'], message: '帖子标题必需填写' })
+    @IsOptional({ groups: ['update'] })
+    title: string;
+
+    @IsNotEmpty({ groups: ['create'], message: '帖子内容必需填写' })
+    @IsOptional({ groups: ['updatae'] })
+    body: string;
+
+    @MaxLength(500, {
+        always: true,
+        message: '帖子描述长度最大为$constraint1',
+    })
+    @IsOptional({ always: true })
+    summary: string;
+}

src/modules/content/dtos/index.ts

@@ -0,0 +1,2 @@
+export * from './create-post.dto';
+export * from './update-post.dto';

src/modules/content/dtos/update-post.dto.ts

@@ -0,0 +1,14 @@
+import { Injectable } from '@nestjs/common';
+
+import { PartialType } from '@nestjs/swagger';
+
+import { IsDefined, IsNumber } from 'class-validator';
+
+import { CreatePostDto } from './create-post.dto';
+
+@Injectable()
+export class UpdatePostDto extends PartialType(CreatePostDto) {
+    @IsNumber(undefined, { groups: ['update'], message: '帖子ID格式错误' })
+    @IsDefined({ groups: ['update'], message: '帖子ID必需指定' })
+    id: number;
+}

src/modules/content/services/index.ts

@@ -0,0 +1 @@
+export * from './post.service';

src/modules/content/services/post.service.ts

@@ -0,0 +1,64 @@
+import { Injectable, NotFoundException } from '@nestjs/common';
+
+import { isNil } from 'lodash';
+
+import { CreatePostDto, UpdatePostDto } from '../dtos';
+
+import { PostEntity } from '../types';
+
+@Injectable()
+export class PostService {
+    protected posts: PostEntity[] = [
+        { title: '第一篇文章标题', body: '第一篇文章内容' },
+        { title: '第二篇文章标题', body: '第二篇文章内容' },
+        { title: '第三篇文章标题', body: '第三篇文章内容' },
+        { title: '第四篇文章标题', body: '第四篇文章内容' },
+        { title: '第五篇文章标题', body: '第五篇文章内容' },
+        { title: '第六篇文章标题', body: '第六篇文章内容' },
+    ].map((v, id) => ({ ...v, id }));
+
+    async findAll() {
+        return this.posts;
+    }
+
+    async findOne(id: number) {
+        const post = this.posts.find((item) => item.id === id);
+
+        if (isNil(post)) throw new NotFoundException(`id: ${id} 文章不存在`);
+
+        return post;
+    }
+
+    async create(data: CreatePostDto) {
+        const newPost: PostEntity = {
+            id: Math.max(...this.posts.map(({ id }) => id + 1)),
+            ...data,
+        };
+
+        this.posts.push(newPost);
+
+        return newPost;
+    }
+
+    async update(data: UpdatePostDto) {
+        let toUpdate = this.posts.find((item) => item.id === data.id);
+
+        if (isNil(toUpdate)) throw new NotFoundException(`id: ${data.id} 文章不存在`);
+
+        toUpdate = { ...toUpdate, ...data };
+
+        this.posts = this.posts.map((item) => (item.id === data.id ? toUpdate : item));
+
+        return toUpdate;
+    }
+
+    async delete(id: number) {
+        const toDelete = this.posts.find((item) => item.id === id);
+
+        if (isNil(toDelete)) throw new NotFoundException(`id: ${id} 文章不存在`);
+
+        this.posts = this.posts.filter((item) => item.id !== id);
+
+        return toDelete;
+    }
+}

src/modules/content/types.ts

@@ -0,0 +1,6 @@
+export interface PostEntity {
+    id: number;
+    title: string;
+    summary?: string;
+    body: string;
+}

src/modules/core/core.module.ts

@@ -0,0 +1,23 @@
+import { DynamicModule, Global, Module } from '@nestjs/common';
+
+import { ConfigService } from './services/config.service';
+
+@Global()
+@Module({})
+export class CoreModule {
+    static forRoot(options: { config: RecordAny }): DynamicModule {
+        return {
+            module: CoreModule,
+            global: true,
+            providers: [
+                {
+                    provide: ConfigService,
+                    useFactory() {
+                        return new ConfigService(options.config);
+                    },
+                },
+            ],
+            exports: [ConfigService],
+        };
+    }
+}

src/modules/core/services/config.service.ts

@@ -0,0 +1,15 @@
+import { Injectable } from '@nestjs/common';
+import { get } from 'lodash';
+
+@Injectable()
+export class ConfigService {
+    protected config: RecordAny = {};
+
+    constructor(data: RecordAny) {
+        this.config = data;
+    }
+
+    get<T>(key: string, defaultValue?: T): T | undefined {
+        return get(this.config, key, defaultValue);
+    }
+}

src/modules/welcome/services/fifth.service.ts

@@ -0,0 +1,15 @@
+import { Injectable, forwardRef, Inject } from '@nestjs/common';
+
+import { SixthService } from './sixth.service';
+
+@Injectable()
+export class FifthService {
+    constructor(
+        @Inject(forwardRef(() => SixthService))
+        protected sixth: WrapperType<SixthService>,
+    ) {}
+
+    circular() {
+        return `FifthService 循环依赖1${this.sixth.circular()}`;
+    }
+}

src/modules/welcome/services/first.service.ts

@@ -0,0 +1,16 @@
+import { Injectable } from '@nestjs/common';
+
+@Injectable()
+export class FirstService {
+    useValue() {
+        return 'FirstService useValue';
+    }
+
+    useId() {
+        return 'FirstService 字符串提供者';
+    }
+
+    useAlias() {
+        return 'FirstService 别名提供者';
+    }
+}

src/modules/welcome/services/fourth.service.ts

@@ -0,0 +1,20 @@
+import { Injectable } from '@nestjs/common';
+
+import { ThirdService } from './third.service';
+
+@Injectable()
+export class FourthService {
+    constructor(private third: ThirdService) {}
+
+    getContent() {
+        return this.third.useFactory();
+    }
+
+    async getPromise() {
+        return new Promise((resolve) => {
+            setTimeout(() => {
+                resolve(this.third);
+            }, 100);
+        });
+    }
+}

src/modules/welcome/services/second.service.ts

@@ -0,0 +1,16 @@
+import { Injectable } from '@nestjs/common';
+
+@Injectable()
+export class SecondService {
+    useClass() {
+        return 'useClass - 2';
+    }
+
+    useFactory() {
+        return '构造器提供者 - 1';
+    }
+
+    useAsync() {
+        return '异步提供者';
+    }
+}

src/modules/welcome/services/sixth.service.ts

@@ -0,0 +1,15 @@
+import { Injectable, forwardRef, Inject } from '@nestjs/common';
+
+import { FifthService } from './fifth.service';
+
+@Injectable()
+export class SixthService {
+    constructor(
+        @Inject(forwardRef(() => FifthService))
+        protected fifth: WrapperType<FifthService>,
+    ) {}
+
+    circular() {
+        return `SixthService 循环依赖2`;
+    }
+}

src/modules/welcome/services/third.service.ts

@@ -0,0 +1,12 @@
+import { Injectable } from '@nestjs/common';
+
+@Injectable()
+export class ThirdService {
+    useClass() {
+        return 'useClass - 3';
+    }
+
+    useFactory() {
+        return '构造器提供者 - 2';
+    }
+}

src/modules/welcome/welcome.controller.ts

@@ -1,12 +1,59 @@
-import { Controller, Get } from '@nestjs/common';
+import { Controller, Get, Inject } from '@nestjs/common';
+
+import { ConfigService } from '../core/services/config.service';
+
+import { FifthService } from './services/fifth.service';
+import { FirstService } from './services/first.service';
+import { FourthService } from './services/fourth.service';
+import { SecondService } from './services/second.service';
 
 /**
  * 欢迎访问 Ink NestJS API
  */
 @Controller()
 export class WelcomeController {
+    constructor(
+        private configService: ConfigService,
+        private first: FirstService,
+        @Inject('ID-WELCOME') private idExp: FirstService,
+        @Inject('FACTORY-WELCOME') private ftExp: FourthService,
+        @Inject('ALIAS-WELCOME') private asExp: FirstService,
+        @Inject('ASYNC-WELCOME') private acExp: SecondService,
+        private fifth: FifthService,
+    ) {}
+
     @Get()
     getMessage(): string {
-        return '访问 ink nestjs api, 了解更多 请联系邮箱 youzegehq@gmail.com';
+        return this.configService.get('name');
+    }
+
+    @Get('value')
+    async useValue() {
+        return this.first.useValue();
+    }
+
+    @Get('id')
+    async useId() {
+        return this.idExp.useId();
+    }
+
+    @Get('factory')
+    async useFactory() {
+        return this.ftExp.getContent();
+    }
+
+    @Get('alias')
+    async useAlias() {
+        return this.asExp.useAlias();
+    }
+
+    @Get('async')
+    async useAsync() {
+        return this.acExp.useAsync();
+    }
+
+    @Get('circular')
+    async useCircular() {
+        return this.fifth.circular();
     }
 }

src/modules/welcome/welcome.module.ts

@@ -0,0 +1,58 @@
+import { Module } from '@nestjs/common';
+
+import { FirstService } from './services/first.service';
+import { FourthService } from './services/fourth.service';
+import { SecondService } from './services/second.service';
+import { ThirdService } from './services/third.service';
+import { WelcomeController } from './welcome.controller';
+import { FifthService } from './services/fifth.service';
+import { SixthService } from './services/sixth.service';
+
+const firstObject = {
+    useValue: () => 'firstObject useValue 提供者',
+    useAlias: () => 'firstObject 别名提供者',
+};
+
+const firstInstance = new FirstService();
+
+@Module({
+    controllers: [WelcomeController],
+    providers: [
+        {
+            provide: FirstService,
+            useValue: firstObject,
+        },
+        {
+            provide: 'ID-WELCOME',
+            useValue: firstInstance,
+        },
+        {
+            provide: SecondService,
+            useClass: ThirdService,
+        },
+        {
+            provide: 'FACTORY-WELCOME',
+            useFactory(second: SecondService) {
+                const factory = new FourthService(second);
+
+                return factory;
+            },
+            inject: [SecondService],
+        },
+        {
+            provide: 'ALIAS-WELCOME',
+            useExisting: FirstService,
+        },
+        {
+            provide: 'ASYNC-WELCOME',
+            useFactory: async () => {
+                const factory = new FourthService(new SecondService());
+
+                return factory.getPromise();
+            },
+        },
+        FifthService,
+        SixthService,
+    ],
+})
+export class WelcomeModule {}

tsconfig.build.json

@@ -1,4 +1,4 @@
 {
   "extends": "./tsconfig.json",
-  "exclude": ["node_modules", "test", "dist", "**/*spec.ts", "**.js"]
+  "exclude": ["node_modules", "test", "dist", "trashed", "back", "**/*spec.ts", "**.js"]
 }

typings/global.d.ts

@@ -0,0 +1,54 @@
+declare type RecordAny = Record<string, any>;
+declare type RecordNever = Record<never, never>;
+declare type RecordAnyOrNever = RecordAny | RecordNever;
+
+/**
+ * 基础类型接口
+ */
+declare type BaseType = boolean | number | string | undefined | null;
+
+/**
+ * 环境变量类型转义函数接口
+ */
+declare type ParseType<T extends BaseType = string> = (value: string) => T;
+
+/**
+ * 类转义为普通对象后的类型
+ */
+declare type ClassToPlain<T> = { [key in keyof T]: T[key] };
+
+/**
+ * 一个类的类型
+ */
+declare type ClassType<T> = { new (...args: any[]): T };
+
+/**
+ * 嵌套对象全部可选
+ */
+declare type RePartial<T> = {
+    [P in keyof T]?: T[P] extends (infer U)[] | undefined
+        ? RePartial<U>[]
+        : T[P] extends object | undefined
+          ? T[P] extends ((...args: any[]) => any) | ClassType<T[P]> | undefined
+              ? T[P]
+              : RePartial<T[P]>
+          : T[P];
+};
+
+/**
+ * 嵌套对象全部必选
+ */
+declare type ReRequired<T> = {
+    [P in keyof T]-?: T[P] extends (infer U)[]
+        ? ReRequired<U>[]
+        : T[P] extends ReadonlyArray<infer V>
+          ? ReadonlyArray<ReRequired<V>>
+          : T[P] extends object
+            ? ReRequired<T[P]>
+            : T[P];
+};
+
+/**
+ * 防止swc下循环依赖报错
+ */
+declare type WrapperType<T> = T;