Lifecycle Events

There're 2 module lifecycle events, the OnModuleInit and OnModuleDestroy. It's a good practice to use them for all the initialization stuff and avoid to put anything directly in the constructor. The constructor should be used only to initialize the class members and inject the required dependencies.

import { Component, OnModuleInit, OnModuleDestroy } from '@nestjs/common';

@Component()
export class UsersService implements OnModuleInit, OnModuleDestroy {
  onModuleInit() {
    console.log(`Module's initialized...`);
  }
  onModuleDestroy() {
    console.log(`Module's destroyed...`);
  }
}

import { Component } from '@nestjs/common';

@Component()
export class UsersService {
  onModuleInit() {
    console.log(`Module's initialized...`);
  }
  onModuleDestroy() {
    console.log(`Module's destroyed...`);
  }
}