taskmanage-nestjs: A TypeScript repository from Avocado0595

Task App Structure

TaskModule
- TasksController
- TasksService
- Status ValidationPipe
- TasksEntity
- TasksRepository
AuthModule
- AuthController
- AuthService
- UserEntity
- UserRepository
- JwtStrategy
- ...
EndPoints
- TasksController: /tasks
  - GET /tasks getAllTasks()
  - GET /tasks/:id getTaskById()
  - POST /tasks createTask()
  - DELETE /tasks/:id deleteTask()
  - PATCH /tasks/:id/ updateTaskStatus()
- AuthController: /auth
  - POST /auth/register register()
  - POST /auth/login login()
  - POST /auth/logout logout()
- UserController: /users
  - GET /users/:id getUserById()
  - POST /users createUser()
  - PATCH /users/:id updateUser()
  - DELETE /users/:id deleteUser()
Nestjs:
- Modules
- Controllers
- Services and Providers
- Controller-to-Service
- Validation using Nestjs Pipes
Architechture
- REST API
- CRUD operation
- Error handling
- DTO (data transfer object)
- System modularity
- Backend best practices
- Configure management
- Logging
- Security
demo flow: main call NestFactory(appmodule) => appmodule(controller, service) **decorator: @Module({ imports: [], controllers: [AppController], providers: [AppService], }) export class AppModule {}

decorator Module({truyen prop nay vao class phia duoi})

NestJs Module

Singletons
a folder per module
define: @Module({})

props:

providers:[]
controllers:[]
exports:[]
imports:[]
example

ForumModule
- PostModule
- CommentModule
  - UserProfileModule
- AuthModule =>

@Module({
    providers:[ForumService],
    controllers:[ForumController],
    imports: [
        PostModule,
        CommentModule,
        AuthModule
    ],
    exports:[ForumService]
})
export class ForumModule{}

NestJs Controller

handle request, return response
bound to path
dependency injection
define:

@Controller('/tasks')
export class TaskController{
    //handle request here
    @Get()
    getAllTasks(){
        return 'get all tasks';
    }
    @Post()
    createTask(){
        return 'create task';
    }
}

Flow 2: HTTP request => controller(endpoint, request data) handle something => communicate service (interact with database) => reponse value (wrap in HTTP response) => return to client

NestJs Provider

denpendency injection (@Injectable())
Service:
- defined as provider (not all providers are services)
- singletons: share with source of truth
- be called from controller to interact with database
- defined:

    @Module({
        cotrollers:[TaskController],
        providers:[TasksService, LoggerService]
    })

install uuid
controller: @Body(key?: string) <=> req.body / req.body[key] => input key nếu ko muốn get cả object
DTO (data transfer object) data flow: http request send object {title, description} => controller recive object {title, description} => call service function => service: add data to db, return result to controller => controller send response to client **object {title, description}: DTO (not a model) **using class **example:

class CreateShippingDto{
    orderId: string;
    shippingAddress: string;
    requiredSignature: boolean;
}

=> túm lại: dùng DTO này để việc truyền data giữa các layer được thống nhất hơn.

Pipes (same middlewares?)

process arguments before calling controller
perform data transformation or validation
return original or modified data
throw exception if data is invalid
can be asynchronous
ValidationPipe: validate dto data, ParseIntPipe: convert string to number
CustomPipe:
use pipes:
- handle-level: @UsePipes(ValidationPipe)
- parameter-level: @Param('id') id: string, @UsePipes(ValidationPipe)
- global pipes: app.useGlobalPipes(somePipe)
chose level?
- parameter: slimmer, cleaner. However: extra code, hard maintain
- handler: more code, greate benefits:
  - do not require extra code at param level
  - easy maintain
  - indentify params
  - promote usage DTOs

*****series này dạy postgresql - lười cài nên dùng mysql ^^ 15. TypeORM 16. Active Record and Data Mapper

Active Record:
- extends baseEntity
- have method: find, findOne,...
- for simple
Data Mapper:
- declare class entity
- set up Repository: extends Repository
- for maintain ** app.module : use TypeOrmModule.forRoot ** task.module : use TypeOrmModule.forFeature([UserEntity, TaskEntity])

authentication: verify who are you
authorization: give somebody permission depend on their indentity
JWT = header (meta data: type, hashing algorithm) + payload (data: user, ...) + signature (encoded header, encoded payload, secret key)
Sử dụng JWT trong nestjs

install: @nestjs/jwt, passport, passport-jwt
import auth.module

imports:[
  PassportModule.register({defaultStrategy: 'jwt'}),
  JwtModule.register({
    secret: 'đặt 1 private key ở đây',
    signOptions:{
      expiresIn: 3600, //thời gian hết hạn của token
    }
  })],

get token: const accessToken: string = this.jwtService.sign(payload);
verify token:
- install: @types/passport-jwt

@Injectable()
export class JwtStrategy extends PassportStrategy(Strategy){
    constructor(@InjectRepository(UsersRepository)
    private userRepository: UsersRepository){
        super({
            secretOrKey: 'private', //add lại secret key ở đây
            jwtFromRequest: ExtractJwt.fromAuthHeaderAsBearerToken(),//extract token từ (bearer) header
        })
    }

    async validate(payload:JwtPayload): Promise<string>{ //method overload từ PassportStrategy,
    // sẽ verify token, decode => payload
        const{username} = payload;
        const user: User = await this.userRepository.findOne({username});
        if(!user){
            throw new UnauthorizedException();
        }

        return "user"; //cái này sẽ trả về request => request này trả về object tên là user ????
        //2 dòng này để loại pasword ra khỏi request trả về
        const { password, ...result } = user;
        return result;
    }
}

+  @UseGuards(AuthGuard()) => đặt middleware này để verify token trước rồi nào cần authorization

decorator để lấy data từ request sau khi verify token

export const GetUser = createParamDecorator((_data, ctx: ExecutionContext):User=>{
    const req = ctx.switchToHttp().getRequest(); //get data từ request
    return req.user; //chỉ lấy user từ token
})

Relationship

@ManyToOne(_type=>User, user=>user.tasks, {eager: false})
    user: User;

{eager: true} => eager loading: load data from other table

@Exclude

@ManyToOne(_type=>User, user=>user.tasks, {eager: false})
    @Exclude({toPlainOnly: true})
    user: User;

đoạn này loại bỏ cột user trong task khi trả về plain object: json cần config thêm: nestInterceptor - instanceToPlain (file: transform.inerceptor)

Socket.io - app chat
Custom AuthGuard

import { Injectable, CanActivate, ExecutionContext } from '@nestjs/common';
import { Observable } from 'rxjs';

@Injectable()
export class AuthGuard implements CanActivate {
  canActivate(
    context: ExecutionContext,
  ): boolean | Promise<boolean> | Observable<boolean> {
    const request = context.switchToHttp().getRequest();//get request từ http
    console.log(request.handshake);
    return true;
  }
}
//use: @UseGuards(AuthGuard)

Dùng configService trong Module

import { ConfigModule, ConfigService } from "@nestjs/config"

export class JwtConfig{ //tạo class base
    static getJwtConfig(configService: ConfigService){ //phương thức static, init ConfigService
      return { //return giá trị cần sử dụng
        secret: configService.get('SECRET_ACCESSTOKEN'),
          signOptions:{
            expiresIn: 36000,
          }
      }
  }
}
  
  export const jwtConfigAsync = { //dùng useFactory để inject ConfigService
    imports:[ConfigModule],
    useFactory: async (configService: ConfigService): Promise<JwtConfig>=>JwtConfig.getJwtConfig(configService),
    inject: [ConfigService]
  }

  //sử dụng
  JwtModule.registerAsync(jwtConfigAsync),

Lỗi EntityRepository deprecated: tạo các file sau để dùng CustomDecorator

typeorm-ex.decorator.ts
typeorm-ex.module.ts

Upload file

install: multer
middleware:

 @UseInterceptors(FileInterceptor('avatar', {
        storage: diskStorage({
            destination: join(resolve(),'/public/avatars'),
            filename:  (_req, _res, cb)=> cb(null, v4() + '.png')
        })
    }))

Avocado0595/taskmanage-nestjs