fix(repository): Move backend code into subdirectory

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

backend/src/users/users.service.ts

@@ -0,0 +1,142 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { Injectable } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+
+import { AlreadyInDBError, NotInDBError } from '../errors/errors';
+import { ConsoleLoggerService } from '../logger/console-logger.service';
+import {
+  FullUserInfoDto,
+  UserInfoDto,
+  UserLoginInfoDto,
+} from './user-info.dto';
+import { UserRelationEnum } from './user-relation.enum';
+import { User } from './user.entity';
+
+@Injectable()
+export class UsersService {
+  constructor(
+    private readonly logger: ConsoleLoggerService,
+    @InjectRepository(User) private userRepository: Repository<User>,
+  ) {
+    this.logger.setContext(UsersService.name);
+  }
+
+  /**
+   * @async
+   * Create a new user with a given username and displayName
+   * @param username - the username the new user shall have
+   * @param displayName - the display name the new user shall have
+   * @return {User} the user
+   * @throws {AlreadyInDBError} the username is already taken.
+   */
+  async createUser(username: string, displayName: string): Promise<User> {
+    const user = User.create(username, displayName);
+    try {
+      return await this.userRepository.save(user);
+    } catch {
+      this.logger.debug(
+        `A user with the username '${username}' already exists.`,
+        'createUser',
+      );
+      throw new AlreadyInDBError(
+        `A user with the username '${username}' already exists.`,
+      );
+    }
+  }
+
+  /**
+   * @async
+   * Delete the user with the specified username
+   * @param {User} user - the username of the user to be delete
+   * @throws {NotInDBError} the username has no user associated with it.
+   */
+  async deleteUser(user: User): Promise<void> {
+    await this.userRepository.remove(user);
+    this.logger.debug(
+      `Successfully deleted user with username ${user.username}`,
+      'deleteUser',
+    );
+  }
+
+  /**
+   * @async
+   * Change the displayName of the specified user
+   * @param {User} user - the user to be changed
+   * @param displayName - the new displayName
+   */
+  async changeDisplayName(user: User, displayName: string): Promise<void> {
+    user.displayName = displayName;
+    await this.userRepository.save(user);
+  }
+
+  /**
+   * @async
+   * Get the user specified by the username
+   * @param {string} username the username by which the user is specified
+   * @param {UserRelationEnum[]} [withRelations=[]] if the returned user object should contain certain relations
+   * @return {User} the specified user
+   */
+  async getUserByUsername(
+    username: string,
+    withRelations: UserRelationEnum[] = [],
+  ): Promise<User> {
+    const user = await this.userRepository.findOne({
+      where: { username: username },
+      relations: withRelations,
+    });
+    if (user === null) {
+      throw new NotInDBError(`User with username '${username}' not found`);
+    }
+    return user;
+  }
+
+  /**
+   * Extract the photoUrl of the user or in case no photo url is present generate a deterministic user photo
+   * @param {User} user - the specified User
+   * @return the url of the photo
+   */
+  getPhotoUrl(user: User): string {
+    if (user.photo) {
+      return user.photo;
+    } else {
+      // TODO: Create new photo, see old code
+      return '';
+    }
+  }
+
+  /**
+   * Build UserInfoDto from a user.
+   * @param {User=} user - the user to use
+   * @return {(UserInfoDto)} the built UserInfoDto
+   */
+  toUserDto(user: User): UserInfoDto {
+    return {
+      username: user.username,
+      displayName: user.displayName,
+      photo: this.getPhotoUrl(user),
+    };
+  }
+
+  /**
+   * Build FullUserInfoDto from a user.
+   * @param {User=} user - the user to use
+   * @return {(UserInfoDto)} the built FullUserInfoDto
+   */
+  toFullUserDto(user: User): FullUserInfoDto {
+    return {
+      username: user.username,
+      displayName: user.displayName,
+      photo: this.getPhotoUrl(user),
+      email: user.email ?? '',
+    };
+  }
+
+  toUserLoginInfoDto(user: User, authProvider: string): UserLoginInfoDto {
+    return { ...this.toUserDto(user), authProvider };
+  }
+}