Services

Services are used to encapsulate the business logic of your application. They are responsible for handling data and implementing the application's logic. Services are used by controllers to handle incoming requests.

Creating a service

To create a new service, create a file in the apps/backend/src/plugins/{your_plugin_code}/services directory. The service should be decorated with the @Injectable() decorator.

import { Injectable } from '@nestjs/common';
import { CreateExampleWelcomeBody } from 'shared/plugins/{your_plugin_code}/example.dto';
 
@Injectable()
export class ExampleWelcomeService {
  create(body: CreateExampleWelcomeBody): string {
    return `This action adds a new example with name: ${body.name} and description: ${body.description}`;
  }
}

The @Injectable() decorator marks the class as a provider. This decorator is required for all providers in NestJS.

Import into module

To use the service, import it into the module where it will be used. Go to the module root of your plugin. That's should be apps/backend/src/plugins/{your_plugin_code}/{your_plugin_code}.module.ts. Import the service and add it to the providers array.

import { Module } from '@nestjs/common';
import { ExampleWelcomeService } from './services/example.service'; 
 
@Module({
  providers: [ExampleWelcomeService], 
})
export class WelcomeModule {}

Usage in controller

To use the service in a controller, import it and inject it into the controller's constructor.

import { Controller, Post, Body } from '@nestjs/common';
import { ExampleWelcomeService } from './services/example.service'; 
import { CreateExampleWelcomeBody } from 'shared/plugins/{your_plugin_code}/example.dto';
 
@Controller('welcome/example')
export class ExampleWelcomeController {
  constructor(private readonly exampleService: ExampleWelcomeService) {} 
 
  @Post()
  create(@Body() body: CreateExampleWelcomeBody) {
    return `This action adds a new example with name: ${body.name} and description: ${body.description}`; 
    return this.exampleService.create(body); 
  }
}