feat(auth): refactor auth, add oidc

Thanks to all HedgeDoc team members for the time discussing,
helping with weird Nest issues, providing feedback
and suggestions!

Co-authored-by: Philip Molares <philip.molares@udo.edu>
Signed-off-by: Philip Molares <philip.molares@udo.edu>
Signed-off-by: Erik Michelson <github@erik.michelson.eu>

backend/src/api/private/auth/ldap/ldap.controller.ts

@@ -0,0 +1,84 @@
+/*
+ * SPDX-FileCopyrightText: 2024 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import {
+  Body,
+  Controller,
+  InternalServerErrorException,
+  Param,
+  Post,
+  Req,
+} from '@nestjs/common';
+import { ApiTags } from '@nestjs/swagger';
+
+import { NotInDBError } from '../../../../errors/errors';
+import { IdentityService } from '../../../../identity/identity.service';
+import { LdapLoginDto } from '../../../../identity/ldap/ldap-login.dto';
+import { LdapService } from '../../../../identity/ldap/ldap.service';
+import { ProviderType } from '../../../../identity/provider-type.enum';
+import { RequestWithSession } from '../../../../identity/session.guard';
+import { ConsoleLoggerService } from '../../../../logger/console-logger.service';
+import { UsersService } from '../../../../users/users.service';
+import { makeUsernameLowercase } from '../../../../utils/username';
+import { OpenApi } from '../../../utils/openapi.decorator';
+
+@ApiTags('auth')
+@Controller('/auth/ldap')
+export class LdapController {
+  constructor(
+    private readonly logger: ConsoleLoggerService,
+    private usersService: UsersService,
+    private ldapService: LdapService,
+    private identityService: IdentityService,
+  ) {
+    this.logger.setContext(LdapController.name);
+  }
+
+  @Post(':ldapIdentifier/login')
+  @OpenApi(200, 400, 401)
+  async loginWithLdap(
+    @Req()
+    request: RequestWithSession,
+    @Param('ldapIdentifier') ldapIdentifier: string,
+    @Body() loginDto: LdapLoginDto,
+  ): Promise<{ newUser: boolean }> {
+    const ldapConfig = this.ldapService.getLdapConfig(ldapIdentifier);
+    const userInfo = await this.ldapService.getUserInfoFromLdap(
+      ldapConfig,
+      loginDto.username,
+      loginDto.password,
+    );
+    try {
+      request.session.authProviderType = ProviderType.LDAP;
+      request.session.authProviderIdentifier = ldapIdentifier;
+      request.session.providerUserId = userInfo.id;
+      await this.identityService.getIdentityFromUserIdAndProviderType(
+        userInfo.id,
+        ProviderType.LDAP,
+        ldapIdentifier,
+      );
+      if (this.identityService.mayUpdateIdentity(ldapIdentifier)) {
+        const user = await this.usersService.getUserByUsername(
+          makeUsernameLowercase(loginDto.username),
+        );
+        await this.usersService.updateUser(
+          user,
+          userInfo.displayName,
+          userInfo.email,
+          userInfo.photoUrl,
+        );
+      }
+      request.session.username = makeUsernameLowercase(loginDto.username);
+      return { newUser: false };
+    } catch (error) {
+      if (error instanceof NotInDBError) {
+        request.session.newUserData = userInfo;
+        return { newUser: true };
+      }
+      this.logger.error(`Error during LDAP login: ${String(error)}`);
+      throw new InternalServerErrorException('Error during LDAP login');
+    }
+  }
+}