From f21ee1d1318b8f1f4d85719b09ec9ca6dfc487b1 Mon Sep 17 00:00:00 2001
From: SauravDhakal <sauravdhakal121@gmail.com>
Date: Sat, 4 Apr 2026 20:53:07 +0545
Subject: [PATCH] feat: Event architecture implemented

---
 common/emails/index.ts    |  5 ++++-
 roadmap.md                |  1 +
 src/app.module.ts         |  2 +-
 src/auth/auth.module.ts   |  4 +---
 src/auth/auth.service.ts  | 12 ++++--------
 src/mail/mail.listener.ts | 12 ++++++++++++
 src/mail/mail.module.ts   |  3 ++-
 src/mail/mail.service.ts  | 19 +++++++++++++++++++
 8 files changed, 44 insertions(+), 14 deletions(-)
 create mode 100644 src/mail/mail.listener.ts

diff --git a/common/emails/index.ts b/common/emails/index.ts
index 80560e5..726d725 100644
--- a/common/emails/index.ts
+++ b/common/emails/index.ts
@@ -1,7 +1,10 @@
 import { welcomeToApp } from "./auth"
 
 const EmailTemplates = {
-  welcomeToApp,
+  signup_completed: {
+    subject: "Welcome to app",
+    body: welcomeToApp
+  },
 }
 
 export default EmailTemplates
diff --git a/roadmap.md b/roadmap.md
index 1e2808e..c1132eb 100644
--- a/roadmap.md
+++ b/roadmap.md
@@ -15,6 +15,7 @@
 ```
 
 2. Also an API of my own
+3. Production and testing env diff
 
 # 🏗️ SaaS Architect’s Roadmap: NestJS & DevOps
 
diff --git a/src/app.module.ts b/src/app.module.ts
index c766dd6..412ddc7 100644
--- a/src/app.module.ts
+++ b/src/app.module.ts
@@ -22,6 +22,7 @@ import { MailModule } from './mail/mail.module';
     ConfigModule.forRoot({
       isGlobal: true,
     }),
+    EventEmitterModule.forRoot(),
     UserModule,
     AuthModule,
     RequestContextModule,
@@ -31,7 +32,6 @@ import { MailModule } from './mail/mail.module';
     AuthorizationModule,
     CacheModule,
     MailModule,
-    EventEmitterModule.forRoot()
   ],
   controllers: [AppController],
   providers: [
diff --git a/src/auth/auth.module.ts b/src/auth/auth.module.ts
index 7e2b83f..5147518 100644
--- a/src/auth/auth.module.ts
+++ b/src/auth/auth.module.ts
@@ -1,12 +1,11 @@
 import { Global, Module } from '@nestjs/common';
 import { AuthService } from './auth.service';
 import { AuthController } from './auth.controller';
-import { APP_GUARD, Reflector } from '@nestjs/core';
+import { APP_GUARD } from '@nestjs/core';
 import { AuthGuard } from './guards/auth.guard';
 import { UserModule } from 'src/user/user.module';
 import { JwtModule } from '@nestjs/jwt';
 import { RequestContextModule } from 'core/als/request-context.module';
-import { MailModule } from 'src/mail/mail.module';
 
 @Global()
 @Module({
@@ -22,7 +21,6 @@ import { MailModule } from 'src/mail/mail.module';
     UserModule,
     JwtModule,
     RequestContextModule,
-    MailModule
   ],
 })
 export class AuthModule { }
diff --git a/src/auth/auth.service.ts b/src/auth/auth.service.ts
index 317bd3a..20caaa4 100644
--- a/src/auth/auth.service.ts
+++ b/src/auth/auth.service.ts
@@ -5,8 +5,7 @@ import * as bcrypt from 'bcrypt';
 import { UserService } from 'src/user/user.service';
 import { TokenInputType } from './types';
 import { JwtService } from '@nestjs/jwt';
-import EmailTemplates from 'common/emails';
-import { MailService } from 'src/mail/mail.service';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 
 @Injectable()
 @Public()
@@ -14,7 +13,7 @@ export class AuthService {
   constructor(
     private readonly userService: UserService,
     private readonly jwtService: JwtService,
-    private readonly mailService: MailService,
+    private readonly eventEmitter: EventEmitter2
   ) { }
 
   async register(dto: RegisterUserRequestDTO) {
@@ -24,11 +23,8 @@ export class AuthService {
       password: hashedPassword,
     });
 
-    this.mailService.sendMail({
-      to: dto.email,
-      subject: "Welcome onboard",
-      body: EmailTemplates.welcomeToApp
-    })
+    this.eventEmitter.emit('user.sign_up', dto.email)
+
     return true;
   }
 
diff --git a/src/mail/mail.listener.ts b/src/mail/mail.listener.ts
new file mode 100644
index 0000000..bb57f05
--- /dev/null
+++ b/src/mail/mail.listener.ts
@@ -0,0 +1,12 @@
+import { Injectable } from "@nestjs/common"
+import { OnEvent } from "@nestjs/event-emitter"
+import { MailService } from "./mail.service"
+
+@Injectable()
+export class MailListener {
+  constructor(private readonly mailService: MailService) { }
+  @OnEvent('user.sign_up')
+  handleUserSignUp(email: string) {
+    this.mailService.sendWelcomeMail({ to: email })
+  }
+}
diff --git a/src/mail/mail.module.ts b/src/mail/mail.module.ts
index 2631d18..b2d2432 100644
--- a/src/mail/mail.module.ts
+++ b/src/mail/mail.module.ts
@@ -1,8 +1,9 @@
 import { Module } from '@nestjs/common';
 import { MailService } from './mail.service';
+import { MailListener } from './mail.listener';
 
 @Module({
-  providers: [MailService],
+  providers: [MailService, MailListener],
   exports: [MailService]
 })
 export class MailModule { }
diff --git a/src/mail/mail.service.ts b/src/mail/mail.service.ts
index aaca171..5f5f2cd 100644
--- a/src/mail/mail.service.ts
+++ b/src/mail/mail.service.ts
@@ -1,5 +1,6 @@
 import { Injectable } from '@nestjs/common';
 import { ConfigService } from "@nestjs/config";
+import EmailTemplates from 'common/emails';
 import * as nodemailer from "nodemailer";
 
 @Injectable()
@@ -30,6 +31,24 @@ export class MailService {
     this.mailServiceAvailable = true;
   }
 
+  /*
+   * SIGN-UP
+   * */
+  sendWelcomeMail({ to }: { to: string }) {
+    if (!this.mailServiceAvailable)
+      throw new Error("Mail service not available")
+
+    const email = EmailTemplates.signup_completed;
+
+    this.transporter.sendMail(
+      {
+        to,
+        subject: email.subject,
+        html: email.body
+      }
+    )
+  }
+
   sendMail({ to, subject, body }: { to: string, subject: string, body: string }) {
     if (!this.mailServiceAvailable)
       throw new Error("Mail service not available")