feat/support smtp email provider

Signed-off-by: pranalidhanavade <pranali.dhanavade@ayanworks.com>

Author: pranalidhanavade

libs/common/src/email.service.ts

@@ -3,6 +3,7 @@ import { Injectable, Logger } from '@nestjs/common';
 import { CommonConstants } from './common.constant';
 import { EmailDto } from './dtos/email.dto';
 import { sendWithResend } from './resend-helper-file';
+import { sendWithSMTP } from './smtp-helper-file';
 import { sendWithSendGrid } from './send-grid-helper-file';
 
 @Injectable()
@@ -23,6 +24,9 @@ export class EmailService {
         case 'resend':
           result = await sendWithResend(emailDto);
           break;
+        case 'smtp':
+          result = await sendWithSMTP(emailDto);
+          break;
         default:
           this.logger.warn(`Unknown email provider: ${provider}, defaulting to SendGrid.`);
           result = await sendWithSendGrid(emailDto);

libs/common/src/resend-helper-file.ts

@@ -6,11 +6,17 @@ import { Resend } from 'resend';
 
 dotenv.config();
 
+const emailProvider = process.env.EMAIL_PROVIDER;
 const apiKey = process.env.RESEND_API_KEY;
-if (!apiKey) {
-  throw new Error('Missing RESEND_API_KEY in environment variables.');
+
+let resend: Resend | null = null;
+
+if ('resend' === emailProvider) {
+  if (!apiKey) {
+    throw new Error('Missing RESEND_API_KEY in environment variables.');
+  }
+  resend = new Resend(apiKey);
 }
-const resend = new Resend(apiKey);
 
 export const sendWithResend = async (emailDto: EmailDto): Promise<boolean> => {
   try {

libs/common/src/smtp-helper-file.ts

@@ -0,0 +1,53 @@
+import * as dotenv from 'dotenv';
+import * as nodemailer from 'nodemailer';
+
+import { EmailDto } from './dtos/email.dto';
+import { Logger } from '@nestjs/common';
+
+dotenv.config();
+
+const emailProvider = process.env.EMAIL_PROVIDER?.toLowerCase();
+
+let transporter: nodemailer.Transporter | null = null;
+
+if ('smtp' === emailProvider) {
+  const { SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASS } = process.env;
+
+  if (!SMTP_HOST || !SMTP_PORT || !SMTP_USER || !SMTP_PASS) {
+    throw new Error('Missing SMTP configuration. Required: SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASS');
+  }
+
+  transporter = nodemailer.createTransport({
+    host: SMTP_HOST,
+    port: Number(SMTP_PORT),
+    secure: 465 === Number(SMTP_PORT),
+    auth: {
+      user: SMTP_USER,
+      pass: SMTP_PASS
+    },
+    requireTLS: 587 === Number(SMTP_PORT)
+  });
+}
+
+export const sendWithSMTP = async (emailDto: EmailDto): Promise<boolean> => {
+  if (!transporter) {
+    Logger.error('SMTP email provider is not initialized');
+    return false;
+  }
+
+  try {
+    await transporter.sendMail({
+      from: emailDto.emailFrom,
+      to: emailDto.emailTo,
+      subject: emailDto.emailSubject,
+      text: emailDto.emailText,
+      html: emailDto.emailHtml,
+      attachments: emailDto.emailAttachments
+    });
+
+    return true;
+  } catch (error) {
+    Logger.error('Error while sending email with SMTP', error);
+    return false;
+  }
+};