chore: modify mailer module

.env.example

@@ -35,9 +35,20 @@ MICROSOFT_SCOPE="user.read"
 MICROSOFT_TENANT="common"
 
 # Mailer config
-MAILER_SMTP_URL="smtps://user@domain.com:pass@smtp.domain.com"
+MAILER_SMTP_ENABLE="true"
+MAILER_USE_ADVANCE_CONFIGS="false"
 MAILER_ADDRESS_FROM='"From Name Here" <from@example.com>'
 
+MAILER_SMTP_URL="smtps://user@domain.com:pass@smtp.domain.com" # used if custom mailer configs is false
+
+# The following are used if custom mailer configs is true
+MAILER_SMTP_HOST="smtp.domain.com"
+MAILER_SMTP_PORT="587"
+MAILER_SMTP_SECURE="true"
+MAILER_SMTP_USER="user@domain.com"
+MAILER_SMTP_PASSWORD="pass"
+MAILER_TLS_REJECT_UNAUTHORIZED="true"
+
 # Rate Limit Config
 RATE_LIMIT_TTL=60 # In seconds
 RATE_LIMIT_MAX=100 # Max requests per IP

packages/hoppscotch-backend/package.json

@@ -30,6 +30,7 @@
     "@nestjs/common": "10.2.7",
     "@nestjs/config": "3.1.1",
     "@nestjs/core": "10.2.7",
+    "@nestjs/event-emitter": "2.0.4",
     "@nestjs/graphql": "12.0.9",
     "@nestjs/jwt": "10.1.1",
     "@nestjs/passport": "10.0.2",

packages/hoppscotch-backend/src/admin/admin.service.spec.ts

@@ -22,6 +22,7 @@ import { ShortcodeService } from 'src/shortcode/shortcode.service';
 import { ConfigService } from '@nestjs/config';
 import { OffsetPaginationArgs } from 'src/types/input-types.args';
 import * as E from 'fp-ts/Either';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 
 const mockPrisma = mockDeep<PrismaService>();
 const mockPubSub = mockDeep<PubSubService>();
@@ -34,6 +35,7 @@ const mockTeamCollectionService = mockDeep<TeamCollectionService>();
 const mockMailerService = mockDeep<MailerService>();
 const mockShortcodeService = mockDeep<ShortcodeService>();
 const mockConfigService = mockDeep<ConfigService>();
+const mockEventEmitter = mockDeep<EventEmitter2>();
 
 const adminService = new AdminService(
   mockUserService,
@@ -44,9 +46,9 @@ const adminService = new AdminService(
   mockTeamInvitationService,
   mockPubSub as any,
   mockPrisma as any,
-  mockMailerService,
   mockShortcodeService,
   mockConfigService,
+  mockEventEmitter,
 );
 
 const invitedUsers: InvitedUsers[] = [

packages/hoppscotch-backend/src/admin/admin.service.ts

@@ -19,7 +19,6 @@ import {
   USER_IS_ADMIN,
   USER_NOT_FOUND,
 } from '../errors';
-import { MailerService } from '../mailer/mailer.service';
 import { InvitedUser } from './invited-user.model';
 import { TeamService } from '../team/team.service';
 import { TeamCollectionService } from '../team-collection/team-collection.service';
@@ -31,6 +30,8 @@ import { ShortcodeService } from 'src/shortcode/shortcode.service';
 import { ConfigService } from '@nestjs/config';
 import { OffsetPaginationArgs } from 'src/types/input-types.args';
 import { UserDeletionResult } from 'src/user/user.model';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { Events } from 'src/types/EventEmitter';
 
 @Injectable()
 export class AdminService {
@@ -43,9 +44,9 @@ export class AdminService {
     private readonly teamInvitationService: TeamInvitationService,
     private readonly pubsub: PubSubService,
     private readonly prisma: PrismaService,
-    private readonly mailerService: MailerService,
     private readonly shortcodeService: ShortcodeService,
     private readonly configService: ConfigService,
+    private readonly eventEmitter: EventEmitter2,
   ) {}
 
   /**
@@ -99,17 +100,16 @@ export class AdminService {
     });
     if (alreadyInvitedUser != null) return E.left(USER_ALREADY_INVITED);
 
-    try {
-      await this.mailerService.sendUserInvitationEmail(inviteeEmail, {
+    this.eventEmitter.emit(Events.MAILER_SEND_USER_INVITATION_EMAIL, {
+      to: inviteeEmail,
+      mailDesc: {
         template: 'user-invitation',
         variables: {
           inviteeEmail: inviteeEmail,
           magicLink: `${this.configService.get('VITE_BASE_URL')}`,
         },
-      });
-    } catch (e) {
-      return E.left(EMAIL_FAILED);
-    }
+      },
+    });
 
     // Add invitee email to the list of invited users by admin
     const dbInvitedUser = await this.prisma.invitedUsers.create({

packages/hoppscotch-backend/src/admin/infra.resolver.ts

@@ -292,6 +292,14 @@ export class InfraResolver {
     return this.infraConfigService.getAllowedAuthProviders();
   }
 
+  @Query(() => Boolean, {
+    description: 'Check if the SMTP is enabled or not',
+  })
+  @UseGuards(GqlAuthGuard)
+  isSMTPEnabled() {
+    return this.infraConfigService.isSMTPEnabled();
+  }
+
   /* Mutations */
 
   @Mutation(() => [InfraConfig], {
@@ -359,4 +367,23 @@ export class InfraResolver {
 
     return true;
   }
+
+  @Mutation(() => Boolean, {
+    description: 'Enable or Disable SMTP for sending emails',
+  })
+  @UseGuards(GqlAuthGuard, GqlAdminGuard)
+  async toggleSMTP(
+    @Args({
+      name: 'status',
+      type: () => ServiceStatus,
+      description: 'Toggle SMTP',
+    })
+    status: ServiceStatus,
+  ) {
+    const isUpdated = await this.infraConfigService.enableAndDisableSMTP(
+      status,
+    );
+    if (E.isLeft(isUpdated)) throwErr(isUpdated.left);
+    return true;
+  }
 }

packages/hoppscotch-backend/src/app.module.ts

@@ -27,9 +27,11 @@ import { MailerModule } from './mailer/mailer.module';
 import { PosthogModule } from './posthog/posthog.module';
 import { ScheduleModule } from '@nestjs/schedule';
 import { HealthModule } from './health/health.module';
+import { EventEmitterModule } from '@nestjs/event-emitter';
 
 @Module({
   imports: [
+    EventEmitterModule.forRoot(),
     ConfigModule.forRoot({
       isGlobal: true,
       load: [async () => loadInfraConfiguration()],

packages/hoppscotch-backend/src/auth/auth.service.spec.ts

@@ -23,6 +23,7 @@ import * as argon2 from 'argon2';
 import * as E from 'fp-ts/Either';
 import { ConfigService } from '@nestjs/config';
 import { InfraConfigService } from 'src/infra-config/infra-config.service';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 
 const mockPrisma = mockDeep<PrismaService>();
 const mockUser = mockDeep<UserService>();
@@ -30,6 +31,7 @@ const mockJWT = mockDeep<JwtService>();
 const mockMailer = mockDeep<MailerService>();
 const mockConfigService = mockDeep<ConfigService>();
 const mockInfraConfigService = mockDeep<InfraConfigService>();
+const mockEventEmitter = mockDeep<EventEmitter2>();
 
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore
@@ -37,9 +39,9 @@ const authService = new AuthService(
   mockUser,
   mockPrisma,
   mockJWT,
-  mockMailer,
   mockConfigService,
   mockInfraConfigService,
+  mockEventEmitter,
 );
 
 const currentTime = new Date();

packages/hoppscotch-backend/src/auth/auth.service.ts

@@ -1,5 +1,4 @@
 import { HttpStatus, Injectable } from '@nestjs/common';
-import { MailerService } from 'src/mailer/mailer.service';
 import { PrismaService } from 'src/prisma/prisma.service';
 import { UserService } from 'src/user/user.service';
 import { VerifyMagicDto } from './dto/verify-magic.dto';
@@ -30,6 +29,8 @@ import { VerificationToken } from '@prisma/client';
 import { Origin } from './helper';
 import { ConfigService } from '@nestjs/config';
 import { InfraConfigService } from 'src/infra-config/infra-config.service';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { Events } from 'src/types/EventEmitter';
 
 @Injectable()
 export class AuthService {
@@ -37,9 +38,9 @@ export class AuthService {
     private usersService: UserService,
     private prismaService: PrismaService,
     private jwtService: JwtService,
-    private readonly mailerService: MailerService,
     private readonly configService: ConfigService,
     private infraConfigService: InfraConfigService,
+    private eventEmitter: EventEmitter2,
   ) {}
 
   /**
@@ -234,11 +235,14 @@ export class AuthService {
         url = this.configService.get('VITE_BASE_URL');
     }
 
-    await this.mailerService.sendEmail(email, {
-      template: 'user-invitation',
-      variables: {
-        inviteeEmail: email,
-        magicLink: `${url}/enter?token=${generatedTokens.token}`,
+    this.eventEmitter.emit(Events.MAILER_SEND_EMAIL, {
+      to: email,
+      mailDesc: {
+        template: 'user-invitation',
+        variables: {
+          inviteeEmail: email,
+          magicLink: `${url}/enter?token=${generatedTokens.token}`,
+        },
       },
     });
 

packages/hoppscotch-backend/src/errors.ts

@@ -678,6 +678,19 @@ export const MAILER_SMTP_URL_UNDEFINED = 'mailer/smtp_url_undefined' as const;
 export const MAILER_FROM_ADDRESS_UNDEFINED =
   'mailer/from_address_undefined' as const;
 
+/**
+ * MAILER_SMTP_USER environment variable is not defined
+ * (MailerModule)
+ */
+export const MAILER_SMTP_USER_UNDEFINED = 'mailer/smtp_user_undefined' as const;
+
+/**
+ * MAILER_SMTP_PASSWORD environment variable is not defined
+ * (MailerModule)
+ */
+export const MAILER_SMTP_PASSWORD_UNDEFINED =
+  'mailer/smtp_password_undefined' as const;
+
 /**
  * SharedRequest invalid request JSON format
  * (ShortcodeService)

packages/hoppscotch-backend/src/infra-config/helper.ts

@@ -33,10 +33,17 @@ const AuthProviderConfigurations = {
     InfraConfigEnum.MICROSOFT_SCOPE,
     InfraConfigEnum.MICROSOFT_TENANT,
   ],
-  [AuthProvider.EMAIL]: [
-    InfraConfigEnum.MAILER_SMTP_URL,
-    InfraConfigEnum.MAILER_ADDRESS_FROM,
-  ],
+  [AuthProvider.EMAIL]: !!process.env.MAILER_USE_CUSTOM_CONFIGS
+    ? [
+        InfraConfigEnum.MAILER_SMTP_HOST,
+        InfraConfigEnum.MAILER_SMTP_PORT,
+        InfraConfigEnum.MAILER_SMTP_SECURE,
+        InfraConfigEnum.MAILER_SMTP_USER,
+        InfraConfigEnum.MAILER_SMTP_PASSWORD,
+        InfraConfigEnum.MAILER_TLS_REJECT_UNAUTHORIZED,
+        InfraConfigEnum.MAILER_ADDRESS_FROM,
+      ]
+    : [InfraConfigEnum.MAILER_SMTP_URL, InfraConfigEnum.MAILER_ADDRESS_FROM],
 };
 
 /**
@@ -75,6 +82,14 @@ export async function getDefaultInfraConfigs(): Promise<
 
   // Prepare rows for 'infra_config' table with default values (from .env) for each 'name'
   const infraConfigDefaultObjs: { name: InfraConfigEnum; value: string }[] = [
+    {
+      name: InfraConfigEnum.MAILER_SMTP_ENABLE,
+      value: process.env.MAILER_SMTP_ENABLE ?? 'true',
+    },
+    {
+      name: InfraConfigEnum.MAILER_USE_CUSTOM_CONFIGS,
+      value: process.env.MAILER_USE_CUSTOM_CONFIGS ?? 'false',
+    },
     {
       name: InfraConfigEnum.MAILER_SMTP_URL,
       value: process.env.MAILER_SMTP_URL,
@@ -83,6 +98,30 @@ export async function getDefaultInfraConfigs(): Promise<
       name: InfraConfigEnum.MAILER_ADDRESS_FROM,
       value: process.env.MAILER_ADDRESS_FROM,
     },
+    {
+      name: InfraConfigEnum.MAILER_SMTP_HOST,
+      value: process.env.MAILER_SMTP_HOST,
+    },
+    {
+      name: InfraConfigEnum.MAILER_SMTP_PORT,
+      value: process.env.MAILER_SMTP_PORT,
+    },
+    {
+      name: InfraConfigEnum.MAILER_SMTP_SECURE,
+      value: process.env.MAILER_SMTP_SECURE,
+    },
+    {
+      name: InfraConfigEnum.MAILER_SMTP_USER,
+      value: process.env.MAILER_SMTP_USER,
+    },
+    {
+      name: InfraConfigEnum.MAILER_SMTP_PASSWORD,
+      value: process.env.MAILER_SMTP_PASSWORD,
+    },
+    {
+      name: InfraConfigEnum.MAILER_TLS_REJECT_UNAUTHORIZED,
+      value: process.env.MAILER_TLS_REJECT_UNAUTHORIZED,
+    },
     {
       name: InfraConfigEnum.GOOGLE_CLIENT_ID,
       value: process.env.GOOGLE_CLIENT_ID,

packages/hoppscotch-backend/src/infra-config/infra-config.service.ts

@@ -43,6 +43,7 @@ export class InfraConfigService implements OnModuleInit {
     InfraConfigEnum.ALLOW_ANALYTICS_COLLECTION,
     InfraConfigEnum.ANALYTICS_USER_ID,
     InfraConfigEnum.IS_FIRST_TIME_INFRA_SETUP,
+    InfraConfigEnum.MAILER_SMTP_ENABLE,
   ];
   // Following fields can not be fetched by `infraConfigs` Query. Use dedicated queries for these fields instead.
   EXCLUDE_FROM_FETCH_CONFIGS = [
@@ -218,6 +219,47 @@ export class InfraConfigService implements OnModuleInit {
     return E.right(isUpdated.right.value === 'true');
   }
 
+  /**
+   * Enable or Disable SMTP
+   * @param status Status to enable or disable
+   * @returns Either true or an error
+   */
+  async enableAndDisableSMTP(status: ServiceStatus) {
+    const isUpdated = await this.toggleServiceStatus(
+      InfraConfigEnum.MAILER_SMTP_ENABLE,
+      status,
+      true,
+    );
+    if (E.isLeft(isUpdated)) return E.left(isUpdated.left);
+
+    if (status === ServiceStatus.DISABLE) {
+      this.enableAndDisableSSO([{ provider: AuthProvider.EMAIL, status }]);
+    }
+    return E.right(true);
+  }
+
+  /**
+   * Enable or Disable Service (i.e. ALLOW_AUDIT_LOGS, ALLOW_ANALYTICS_COLLECTION, ALLOW_DOMAIN_WHITELISTING, SITE_PROTECTION)
+   * @param configName Name of the InfraConfigEnum
+   * @param status Status to enable or disable
+   * @param restartEnabled If true, restart the app after updating the InfraConfig
+   * @returns Either true or an error
+   */
+  async toggleServiceStatus(
+    configName: InfraConfigEnum,
+    status: ServiceStatus,
+    restartEnabled = false,
+  ) {
+    const isUpdated = await this.update(
+      configName,
+      status === ServiceStatus.ENABLE ? 'true' : 'false',
+      restartEnabled,
+    );
+    if (E.isLeft(isUpdated)) return E.left(isUpdated.left);
+
+    return E.right(true);
+  }
+
   /**
    * Enable or Disable SSO for login/signup
    * @param provider Auth Provider to enable or disable
@@ -316,6 +358,16 @@ export class InfraConfigService implements OnModuleInit {
       .split(',');
   }
 
+  /**
+   * Check if SMTP is enabled or not
+   * @returns boolean
+   */
+  isSMTPEnabled() {
+    return (
+      this.configService.get<string>('INFRA.MAILER_SMTP_ENABLE') === 'true'
+    );
+  }
+
   /**
    * Reset all the InfraConfigs to their default values (from .env)
    */
@@ -363,6 +415,20 @@ export class InfraConfigService implements OnModuleInit {
   ) {
     for (let i = 0; i < infraConfigs.length; i++) {
       switch (infraConfigs[i].name) {
+        case InfraConfigEnum.MAILER_SMTP_ENABLE:
+          if (
+            infraConfigs[i].value !== 'true' &&
+            infraConfigs[i].value !== 'false'
+          )
+            return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_USE_CUSTOM_CONFIGS:
+          if (
+            infraConfigs[i].value !== 'true' &&
+            infraConfigs[i].value !== 'false'
+          )
+            return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
         case InfraConfigEnum.MAILER_SMTP_URL:
           const isValidUrl = validateSMTPUrl(infraConfigs[i].value);
           if (!isValidUrl) return E.left(INFRA_CONFIG_INVALID_INPUT);
@@ -371,6 +437,32 @@ export class InfraConfigService implements OnModuleInit {
           const isValidEmail = validateSMTPEmail(infraConfigs[i].value);
           if (!isValidEmail) return E.left(INFRA_CONFIG_INVALID_INPUT);
           break;
+        case InfraConfigEnum.MAILER_SMTP_HOST:
+          if (!infraConfigs[i].value) return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_SMTP_PORT:
+          if (!infraConfigs[i].value) return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_SMTP_SECURE:
+          if (
+            infraConfigs[i].value !== 'true' &&
+            infraConfigs[i].value !== 'false'
+          )
+            return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_SMTP_USER:
+          if (!infraConfigs[i].value) return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_SMTP_PASSWORD:
+          if (!infraConfigs[i].value) return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
+        case InfraConfigEnum.MAILER_TLS_REJECT_UNAUTHORIZED:
+          if (
+            infraConfigs[i].value !== 'true' &&
+            infraConfigs[i].value !== 'false'
+          )
+            return E.left(INFRA_CONFIG_INVALID_INPUT);
+          break;
         case InfraConfigEnum.GOOGLE_CLIENT_ID:
           if (!infraConfigs[i].value) return E.left(INFRA_CONFIG_INVALID_INPUT);
           break;

packages/hoppscotch-backend/src/mailer/mailer.listener.ts

@@ -0,0 +1,30 @@
+import { Injectable } from '@nestjs/common';
+import { OnEvent } from '@nestjs/event-emitter';
+import { Events } from 'src/types/EventEmitter';
+import {
+  AdminUserInvitationMailDescription,
+  MailDescription,
+  UserMagicLinkMailDescription,
+} from './MailDescriptions';
+import { MailerService } from './mailer.service';
+
+@Injectable()
+export class MailerEventListener {
+  constructor(private mailerService: MailerService) {}
+
+  @OnEvent(Events.MAILER_SEND_EMAIL, { async: true })
+  async handleSendEmailEvent(data: {
+    to: string;
+    mailDesc: MailDescription | UserMagicLinkMailDescription;
+  }) {
+    await this.mailerService.sendEmail(data.to, data.mailDesc);
+  }
+
+  @OnEvent(Events.MAILER_SEND_USER_INVITATION_EMAIL, { async: true })
+  async handleSendUserInvitationEmailEvent(data: {
+    to: string;
+    mailDesc: AdminUserInvitationMailDescription;
+  }) {
+    await this.mailerService.sendUserInvitationEmail(data.to, data.mailDesc);
+  }
+}

packages/hoppscotch-backend/src/mailer/mailer.module.ts

@@ -4,38 +4,43 @@ import { HandlebarsAdapter } from '@nestjs-modules/mailer/dist/adapters/handleba
 import { MailerService } from './mailer.service';
 import { throwErr } from 'src/utils';
 import {
-  MAILER_FROM_ADDRESS_UNDEFINED,
+  MAILER_SMTP_PASSWORD_UNDEFINED,
   MAILER_SMTP_URL_UNDEFINED,
+  MAILER_SMTP_USER_UNDEFINED,
 } from 'src/errors';
 import { ConfigService } from '@nestjs/config';
 import { loadInfraConfiguration } from 'src/infra-config/helper';
+import { MailerEventListener } from './mailer.listener';
+import { TransportType } from '@nestjs-modules/mailer/dist/interfaces/mailer-options.interface';
 
 @Global()
-@Module({
-  imports: [],
-  providers: [MailerService],
-  exports: [MailerService],
-})
+@Module({})
 export class MailerModule {
   static async register() {
+    const config = new ConfigService();
     const env = await loadInfraConfiguration();
 
-    let mailerSmtpUrl = env.INFRA.MAILER_SMTP_URL;
-    let mailerAddressFrom = env.INFRA.MAILER_ADDRESS_FROM;
-
-    if (!env.INFRA.MAILER_SMTP_URL || !env.INFRA.MAILER_ADDRESS_FROM) {
-      const config = new ConfigService();
-      mailerSmtpUrl = config.get('MAILER_SMTP_URL');
-      mailerAddressFrom = config.get('MAILER_ADDRESS_FROM');
+    // If mailer SMTP is DISABLED, return the module without any configuration (service, listener, etc.)
+    if (env.INFRA.MAILER_SMTP_ENABLE !== 'true') {
+      console.log('Mailer SMTP is disabled');
+      return { module: MailerModule };
     }
 
+    // If mailer is ENABLED, return the module with configuration (service, listener, etc.)
+
+    // Determine transport configuration based on custom config flag
+    let transportOption = getTransportOption(env, config);
+    // Get mailer address from environment or config
+    const mailerAddressFrom = getMailerAddressFrom(env, config);
+
     return {
       module: MailerModule,
+      providers: [MailerService, MailerEventListener],
       imports: [
         NestMailerModule.forRoot({
-          transport: mailerSmtpUrl ?? throwErr(MAILER_SMTP_URL_UNDEFINED),
+          transport: transportOption,
           defaults: {
-            from: mailerAddressFrom ?? throwErr(MAILER_FROM_ADDRESS_UNDEFINED),
+            from: mailerAddressFrom,
           },
           template: {
             dir: __dirname + '/templates',
@@ -46,3 +51,52 @@ export class MailerModule {
     };
   }
 }
+
+function isEnabled(value) {
+  return value === 'true';
+}
+function getMailerAddressFrom(env, config): string {
+  return (
+    env.INFRA.MAILER_ADDRESS_FROM ??
+    config.get('MAILER_ADDRESS_FROM') ??
+    throwErr(MAILER_SMTP_URL_UNDEFINED)
+  );
+}
+function getTransportOption(env, config): TransportType {
+  const useCustomConfigs = isEnabled(
+    env.INFRA.MAILER_USE_CUSTOM_CONFIGS ??
+      config.get('MAILER_USE_CUSTOM_CONFIGS'),
+  );
+
+  if (!useCustomConfigs) {
+    console.log('Using simple mailer configuration');
+    return (
+      env.INFRA.MAILER_SMTP_URL ??
+      config.get('MAILER_SMTP_URL') ??
+      throwErr(MAILER_SMTP_URL_UNDEFINED)
+    );
+  } else {
+    console.log('Using advanced mailer configuration');
+    return {
+      host: env.INFRA.MAILER_SMTP_HOST ?? config.get('MAILER_SMTP_HOST'),
+      port: +env.INFRA.MAILER_SMTP_PORT ?? +config.get('MAILER_SMTP_PORT'),
+      secure:
+        !!env.INFRA.MAILER_SMTP_SECURE ?? !!config.get('MAILER_SMTP_SECURE'),
+      auth: {
+        user:
+          env.INFRA.MAILER_SMTP_USER ??
+          config.get('MAILER_SMTP_USER') ??
+          throwErr(MAILER_SMTP_USER_UNDEFINED),
+        pass:
+          env.INFRA.MAILER_SMTP_PASSWORD ??
+          config.get('MAILER_SMTP_PASSWORD') ??
+          throwErr(MAILER_SMTP_PASSWORD_UNDEFINED),
+      },
+      tls: {
+        rejectUnauthorized:
+          !!env.INFRA.MAILER_TLS_REJECT_UNAUTHORIZED ??
+          !!config.get('MAILER_TLS_REJECT_UNAUTHORIZED'),
+      },
+    };
+  }
+}

packages/hoppscotch-backend/src/mailer/mailer.service.ts

@@ -7,10 +7,14 @@ import {
 import { throwErr } from 'src/utils';
 import { EMAIL_FAILED } from 'src/errors';
 import { MailerService as NestMailerService } from '@nestjs-modules/mailer';
+import { ConfigService } from '@nestjs/config';
 
 @Injectable()
 export class MailerService {
-  constructor(private readonly nestMailerService: NestMailerService) {}
+  constructor(
+    private readonly nestMailerService: NestMailerService,
+    private readonly configService: ConfigService,
+  ) {}
 
   /**
    * Takes an input mail description and spits out the Email subject required for it
@@ -42,6 +46,8 @@ export class MailerService {
     to: string,
     mailDesc: MailDescription | UserMagicLinkMailDescription,
   ) {
+    if (this.configService.get('INFRA.MAILER_SMTP_ENABLE') !== 'true') return;
+
     try {
       await this.nestMailerService.sendMail({
         to,
@@ -64,6 +70,8 @@ export class MailerService {
     to: string,
     mailDesc: AdminUserInvitationMailDescription,
   ) {
+    if (this.configService.get('INFRA.MAILER_SMTP_ENABLE') !== 'true') return;
+
     try {
       const res = await this.nestMailerService.sendMail({
         to,

packages/hoppscotch-backend/src/team-invitation/team-invitation.service.ts

@@ -15,12 +15,13 @@ import {
   TEAM_MEMBER_NOT_FOUND,
 } from 'src/errors';
 import { TeamInvitation } from './team-invitation.model';
-import { MailerService } from 'src/mailer/mailer.service';
 import { UserService } from 'src/user/user.service';
 import { PubSubService } from 'src/pubsub/pubsub.service';
 import { validateEmail } from '../utils';
 import { AuthUser } from 'src/types/AuthUser';
 import { ConfigService } from '@nestjs/config';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { Events } from 'src/types/EventEmitter';
 
 @Injectable()
 export class TeamInvitationService {
@@ -28,9 +29,9 @@ export class TeamInvitationService {
     private readonly prisma: PrismaService,
     private readonly userService: UserService,
     private readonly teamService: TeamService,
-    private readonly mailerService: MailerService,
     private readonly pubsub: PubSubService,
     private readonly configService: ConfigService,
+    private eventEmitter: EventEmitter2,
   ) {}
 
   /**
@@ -147,14 +148,17 @@ export class TeamInvitationService {
       },
     });
 
-    await this.mailerService.sendEmail(inviteeEmail, {
-      template: 'team-invitation',
-      variables: {
-        invitee: creator.displayName ?? 'A Hoppscotch User',
-        action_url: `${this.configService.get('VITE_BASE_URL')}/join-team?id=${
-          dbInvitation.id
-        }`,
-        invite_team_name: team.name,
+    this.eventEmitter.emit(Events.MAILER_SEND_EMAIL, {
+      to: inviteeEmail,
+      mailDesc: {
+        template: 'team-invitation',
+        variables: {
+          invitee: creator.displayName ?? 'A Hoppscotch User',
+          action_url: `${this.configService.get(
+            'VITE_BASE_URL',
+          )}/join-team?id=${dbInvitation.id}`,
+          invite_team_name: team.name,
+        },
       },
     });
 

packages/hoppscotch-backend/src/types/EventEmitter.ts

@@ -0,0 +1,4 @@
+export enum Events {
+  MAILER_SEND_EMAIL = 'mailer.sendEmail',
+  MAILER_SEND_USER_INVITATION_EMAIL = 'mailer.sendUserInvitationEmail',
+}

packages/hoppscotch-backend/src/types/InfraConfig.ts

@@ -1,7 +1,16 @@
 export enum InfraConfigEnum {
+  MAILER_SMTP_ENABLE = 'MAILER_SMTP_ENABLE',
+  MAILER_USE_CUSTOM_CONFIGS = 'MAILER_USE_CUSTOM_CONFIGS',
   MAILER_SMTP_URL = 'MAILER_SMTP_URL',
   MAILER_ADDRESS_FROM = 'MAILER_ADDRESS_FROM',
 
+  MAILER_SMTP_HOST = 'MAILER_SMTP_HOST',
+  MAILER_SMTP_PORT = 'MAILER_SMTP_PORT',
+  MAILER_SMTP_SECURE = 'MAILER_SMTP_SECURE',
+  MAILER_SMTP_USER = 'MAILER_SMTP_USER',
+  MAILER_SMTP_PASSWORD = 'MAILER_SMTP_PASSWORD',
+  MAILER_TLS_REJECT_UNAUTHORIZED = 'MAILER_TLS_REJECT_UNAUTHORIZED',
+
   GOOGLE_CLIENT_ID = 'GOOGLE_CLIENT_ID',
   GOOGLE_CLIENT_SECRET = 'GOOGLE_CLIENT_SECRET',
   GOOGLE_CALLBACK_URL = 'GOOGLE_CALLBACK_URL',