✨ Add registration with email conflict check

src/app.module.ts

@@ -1,13 +1,21 @@
 import { Module } from '@nestjs/common';
+import { APP_INTERCEPTOR } from '@nestjs/core';
+import { RateLimiterInterceptor, RateLimiterModule } from 'nestjs-rate-limiter';
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 import { AuthModule } from './modules/auth/auth.module';
 import { PrismaModule } from './modules/prisma/prisma.module';
 import { UsersModule } from './modules/user/user.module';
 
 @Module({
-  imports: [PrismaModule, UsersModule, AuthModule],
+  imports: [PrismaModule, UsersModule, AuthModule, RateLimiterModule],
   controllers: [AppController],
-  providers: [AppService],
+  providers: [
+    AppService,
+    {
+      provide: APP_INTERCEPTOR,
+      useClass: RateLimiterInterceptor,
+    },
+  ],
 })
 export class AppModule {}

src/modules/auth/auth.controller.ts

@@ -1,5 +1,6 @@
 import { Body, Controller, Post } from '@nestjs/common';
 import { users } from '@prisma/client';
+import { RateLimit } from 'nestjs-rate-limiter';
 import { OmitSecrets } from 'src/modules/prisma/prisma.interface';
 import { RegisterDto } from './auth.dto';
 import { AuthService } from './auth.service';
@@ -9,6 +10,11 @@ export class AuthController {
   constructor(private authService: AuthService) {}
 
   @Post('register')
+  @RateLimit({
+    points: 10,
+    duration: 60,
+    errorMessage: 'Wait for 60 seconds before trying to create an account',
+  })
   async update(@Body() data: RegisterDto): Promise<OmitSecrets<users>> {
     return this.authService.register(data);
   }

src/modules/auth/auth.module.ts

@@ -1,11 +1,12 @@
 import { Module } from '@nestjs/common';
 import { PrismaModule } from '../prisma/prisma.module';
+import { UsersService } from '../user/user.service';
 import { AuthController } from './auth.controller';
 import { AuthService } from './auth.service';
 
 @Module({
   imports: [PrismaModule],
   controllers: [AuthController],
-  providers: [AuthService],
+  providers: [AuthService, UsersService],
 })
 export class AuthModule {}

src/modules/auth/auth.service.ts

@@ -1,14 +1,37 @@
-import { Injectable } from '@nestjs/common';
-import { users, usersCreateInput } from '@prisma/client';
+import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
+import { users } from '@prisma/client';
+import { OmitSecrets } from '../prisma/prisma.interface';
 import { PrismaService } from '../prisma/prisma.service';
+import { UsersService } from '../user/user.service';
+import { RegisterDto } from './auth.dto';
 
 @Injectable()
 export class AuthService {
-  constructor(private prisma: PrismaService) {}
+  constructor(private prisma: PrismaService, private users: UsersService) {}
 
-  async register(data: usersCreateInput): Promise<users> {
-    return this.prisma.users.create({
-      data,
+  async register(data: RegisterDto): Promise<OmitSecrets<users>> {
+    const email = data.email;
+    const emailSafe = this.users.getSafeEmail(email);
+    delete data.email;
+
+    const users = await this.users.users({
+      take: 1,
+      where: { emails: { some: { emailSafe } } },
+    });
+    if (users.length)
+      throw new HttpException(
+        'A user with this email already exists',
+        HttpStatus.CONFLICT,
+      );
+
+    const user = await this.prisma.users.create({
+      data: {
+        ...data,
+        emails: {
+          create: { email: email, emailSafe },
+        },
+      },
     });
+    return this.prisma.expose(user);
   }
 }

src/modules/user/user.service.ts

@@ -66,4 +66,10 @@ export class UsersService {
     });
     return this.prisma.expose<users>(user);
   }
+
+  getSafeEmail(email: string) {
+    email = email.toLowerCase();
+    email = `${email.split('@', 1)[0].split('+')}[0]@${email.split('@', 1)[1]}`;
+    return email;
+  }
 }