Using mailgun in NestJS

I will introduce the basics of using mailgun in NestJS.
Among them, we will focus on implementing the basic code in Quickstart.

How to start sending email - Mailgun API documentation

First install the package.

yarn add mailgun.js
yarn add form-data

Mailgun code is separated into service.

Create a new service and create a method to send mail.
The part to get the secret key using ConfigService is also created.

import { Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import Mailgun from 'mailgun.js';
import FormData from 'form-data';
@Injectable()
export class MailgunService {
  constructor(private readonly config: ConfigService) {}
  // mailgun secret key
  private MAILGUN_KEY = this.config.get<string>('MAILGUN_KEY');
  private MAILGUN_DOMAIN = this.config.get<string>('MAILGUN_DOMAIN');
  private client = new Mailgun(FormData).client({
    username: 'api',
    key: this.MAILGUN_KEY,
  });
  /**
   * Send via API
   *
   * @param data
   */
  async sendMail(data) {
    this.client.messages
      .create(this.MAILGUN_DOMAIN, data)
      .then((res) => {
        console.log(res);
      })
      .catch((err) => {
        console.error(err);
      });
  }
}

The API to send mail is implemented in the app controller.

import { Controller, Get } from '@nestjs/common';
import { AppService } from './app.service';
import { MailgunService } from './providers/mailgun/mailgun.service';
@Controller()
export class AppController {
  constructor(
    private readonly appService: AppService,
    private readonly mailgunService: MailgunService,
  ) {}
  @Get()
  getHello(): string {
    return this.appService.getHello();
  }
  @Get('mail')
  getMail() {
    const messageData = {
      from: 'Excited User <me@samples.mailgun.org>',
      to: 'foo@example.com, bar@example.com',
      subject: 'Hello',
      text: 'Testing some Mailgun awesomeness!',
    };
  this.mailgunService.sendMail(messageData);
  }
}

If the module is even coded and executed, an error may occur.

A TypeError is raised with the message this.FormDataConstructor is not a constructor.

To prevent this, add esModuleInterop to true in tsconfig.json.

I share the full code here.

GitHub - calc2te/nestjs-mailgun: Running mailgun in NestJS