feat(backend): forgot password (#250)

* feat(backend): forgot password

* feat: apply feedback from code review

* chore(auth): validate the minimum length of 'newPassword'

* chore(auth): make token has an expiry of 1 hour

* chore: rename all occurrences of 'code' to 'token'

* chore(backend): provide value on nanoIdGen method

apps/server/src/core/auth/auth.controller.ts

@@ -19,6 +19,7 @@ import { AuthUser } from '../../common/decorators/auth-user.decorator';
 import { User, Workspace } from '@docmost/db/types/entity.types';
 import { AuthWorkspace } from '../../common/decorators/auth-workspace.decorator';
 import { JwtAuthGuard } from '../../common/guards/jwt-auth.guard';
+import { ForgotPasswordDto } from './dto/forgot-password.dto';
 
 @Controller('auth')
 export class AuthController {
@@ -33,6 +34,18 @@ export class AuthController {
     return this.authService.login(loginInput, req.raw.workspaceId);
   }
 
+  @HttpCode(HttpStatus.OK)
+  @Post('forgot-password')
+  async forgotPassword(
+    @Req() req,
+    @Body() forgotPasswordDto: ForgotPasswordDto,
+  ) {
+    return this.authService.forgotPassword(
+      forgotPasswordDto,
+      req.raw.workspaceId,
+    );
+  }
+
   /* @HttpCode(HttpStatus.OK)
   @Post('register')
   async register(@Req() req, @Body() createUserDto: CreateUserDto) {

apps/server/src/core/auth/dto/forgot-password.dto.ts

@@ -0,0 +1,16 @@
+import { IsEmail, IsNotEmpty, IsOptional, IsString, MinLength } from 'class-validator';
+
+export class ForgotPasswordDto {
+  @IsNotEmpty()
+  @IsEmail()
+  email: string;
+
+  @IsOptional()
+  @IsString()
+  token: string;
+
+  @IsOptional()
+  @IsString()
+  @MinLength(8)
+  newPassword: string;
+}

apps/server/src/core/auth/services/auth.service.ts

@@ -11,10 +11,13 @@ import { TokensDto } from '../dto/tokens.dto';
 import { SignupService } from './signup.service';
 import { CreateAdminUserDto } from '../dto/create-admin-user.dto';
 import { UserRepo } from '@docmost/db/repos/user/user.repo';
-import { comparePasswordHash, hashPassword } from '../../../common/helpers';
+import { comparePasswordHash, hashPassword, nanoIdGen } from '../../../common/helpers';
 import { ChangePasswordDto } from '../dto/change-password.dto';
 import { MailService } from '../../../integrations/mail/mail.service';
 import ChangePasswordEmail from '@docmost/transactional/emails/change-password-email';
+import { ForgotPasswordDto } from '../dto/forgot-password.dto';
+import ForgotPasswordEmail from '@docmost/transactional/emails/forgot-password-email';
+import { UserTokensRepo } from '@docmost/db/repos/user-tokens/user-tokens.repo';
 
 @Injectable()
 export class AuthService {
@@ -22,6 +25,7 @@ export class AuthService {
     private signupService: SignupService,
     private tokenService: TokenService,
     private userRepo: UserRepo,
+    private userTokensRepo: UserTokensRepo,
     private mailService: MailService,
   ) {}
 
@@ -46,6 +50,94 @@ export class AuthService {
     return { tokens };
   }
 
+  async forgotPassword(
+    forgotPasswordDto: ForgotPasswordDto,
+    workspaceId: string,
+  ) {
+    const user = await this.userRepo.findByEmail(
+      forgotPasswordDto.email,
+      workspaceId,
+      true,
+    );
+    if (!user) {
+      return;
+    }
+
+    if (
+      forgotPasswordDto.token == null ||
+      forgotPasswordDto.newPassword == null
+    ) {
+      // Generate 5-character user token
+      const code = nanoIdGen(5).toUpperCase();
+      const hashedToken = await hashPassword(code);
+      await this.userTokensRepo.insertUserToken({
+        token: hashedToken,
+        user_id: user.id,
+        workspace_id: user.workspaceId,
+        expires_at: new Date(new Date().getTime() + 3_600_000), // should expires in 1 hour
+        type: "forgot-password",
+      });
+
+      const emailTemplate = ForgotPasswordEmail({
+        username: user.name,
+        code: code,
+      });
+      await this.mailService.sendToQueue({
+        to: user.email,
+        subject: 'Reset your password',
+        template: emailTemplate,
+      });
+
+      return;
+    }
+
+    // Get all user tokens that are not expired
+    const userTokens = await this.userTokensRepo.findByUserId(
+      user.id,
+      user.workspaceId,
+      "forgot-password"
+    );
+    // Limit to the last 3 token, so we have a total time window of 15 minutes
+    const validUserTokens = userTokens
+      .filter((token) => token.expires_at > new Date() && token.used_at == null)
+      .slice(0, 3);
+
+    for (const token of validUserTokens) {
+      const validated = await comparePasswordHash(
+        forgotPasswordDto.token,
+        token.token,
+      );
+      if (validated) {
+        await Promise.all([
+          this.userTokensRepo.deleteUserToken(user.id, user.workspaceId, "forgot-password"),
+          this.userTokensRepo.deleteExpiredUserTokens(),
+        ]);
+
+        const newPasswordHash = await hashPassword(
+          forgotPasswordDto.newPassword,
+        );
+        await this.userRepo.updateUser(
+          {
+            password: newPasswordHash,
+          },
+          user.id,
+          workspaceId,
+        );
+
+        const emailTemplate = ChangePasswordEmail({ username: user.name });
+        await this.mailService.sendToQueue({
+          to: user.email,
+          subject: 'Your password has been changed',
+          template: emailTemplate,
+        });
+
+        return;
+      }
+    }
+
+    throw new BadRequestException('Incorrect code');
+  }
+
   async register(createUserDto: CreateUserDto, workspaceId: string) {
     const user = await this.signupService.signup(createUserDto, workspaceId);