GroupsService: Create new GroupsService

This service is necessary as we plan to have functions to create and manipulate groups in the future.
The GroupInfoDto was moved from the file note-permissions.dto.ts to mimic the UserInfoDto.

Signed-off-by: Philip Molares <philip.molares@udo.edu>

src/groups/group-info.dto.ts

@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { IsBoolean, IsString } from 'class-validator';
+
+export class GroupInfoDto {
+  /**
+   * Name of the group
+   * @example "superheroes"
+   */
+  @IsString()
+  name: string;
+
+  /**
+   * Display name of this group
+   * @example "Superheroes"
+   */
+  @IsString()
+  displayName: string;
+
+  /**
+   * True if this group must be specially handled
+   * Used for e.g. "everybody", "all logged in users"
+   * @example false
+   */
+  @IsBoolean()
+  special: boolean;
+}

src/groups/group.entity.ts

@@ -40,4 +40,15 @@ export class Group {
   })
   @JoinTable()
   members: User[];
+
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  private constructor() {}
+
+  public static create(name: string, displayName: string): Group {
+    const newGroup = new Group();
+    newGroup.special = false; // this attribute should only be true for the two special groups
+    newGroup.name = name;
+    newGroup.displayName = displayName;
+    return newGroup;
+  }
 }

src/groups/groups.module.ts

@@ -7,8 +7,12 @@
 import { Module } from '@nestjs/common';
 import { TypeOrmModule } from '@nestjs/typeorm';
 import { Group } from './group.entity';
+import { GroupsService } from './groups.service';
+import { LoggerModule } from '../logger/logger.module';
 
 @Module({
-  imports: [TypeOrmModule.forFeature([Group])],
+  imports: [TypeOrmModule.forFeature([Group]), LoggerModule],
+  providers: [GroupsService],
+  exports: [GroupsService],
 })
 export class GroupsModule {}

src/groups/groups.service.spec.ts

@@ -0,0 +1,75 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { Test, TestingModule } from '@nestjs/testing';
+import { GroupsService } from './groups.service';
+import { getRepositoryToken } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+import { Group } from './group.entity';
+import { NotInDBError } from '../errors/errors';
+import { LoggerModule } from '../logger/logger.module';
+
+describe('GroupsService', () => {
+  let service: GroupsService;
+  let groupRepo: Repository<Group>;
+  let group: Group;
+
+  beforeAll(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [
+        GroupsService,
+        {
+          provide: getRepositoryToken(Group),
+          useClass: Repository,
+        },
+      ],
+      imports: [LoggerModule],
+    }).compile();
+
+    service = module.get<GroupsService>(GroupsService);
+    groupRepo = module.get<Repository<Group>>(getRepositoryToken(Group));
+    group = Group.create('testGroup', 'Superheros') as Group;
+  });
+
+  it('should be defined', () => {
+    expect(service).toBeDefined();
+  });
+
+  describe('getGroupByName', () => {
+    it('works', async () => {
+      jest.spyOn(groupRepo, 'findOne').mockResolvedValueOnce(group);
+      const foundGroup = await service.getGroupByName(group.name);
+      expect(foundGroup.name).toEqual(group.name);
+      expect(foundGroup.displayName).toEqual(group.displayName);
+      expect(foundGroup.special).toEqual(group.special);
+    });
+    it('fails with non-existing group', async () => {
+      jest.spyOn(groupRepo, 'findOne').mockResolvedValueOnce(undefined);
+      try {
+        await service.getGroupByName('i_dont_exist');
+      } catch (e) {
+        expect(e).toBeInstanceOf(NotInDBError);
+      }
+    });
+  });
+
+  describe('toGroupDto', () => {
+    it('works', () => {
+      const groupDto = service.toGroupDto(group);
+      expect(groupDto.displayName).toEqual(group.displayName);
+      expect(groupDto.name).toEqual(group.name);
+      expect(groupDto.special).toBeFalsy();
+    });
+    it('fails with null parameter', () => {
+      const groupDto = service.toGroupDto(null);
+      expect(groupDto).toBeNull();
+    });
+    it('fails with undefined parameter', () => {
+      const groupDto = service.toGroupDto(undefined);
+      expect(groupDto).toBeNull();
+    });
+  });
+});

src/groups/groups.service.ts

@@ -0,0 +1,57 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { Injectable } from '@nestjs/common';
+import { ConsoleLoggerService } from '../logger/console-logger.service';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+import { Group } from './group.entity';
+import { NotInDBError } from '../errors/errors';
+import { GroupInfoDto } from './group-info.dto';
+
+@Injectable()
+export class GroupsService {
+  constructor(
+    private readonly logger: ConsoleLoggerService,
+    @InjectRepository(Group) private groupRepository: Repository<Group>,
+  ) {
+    this.logger.setContext(GroupsService.name);
+  }
+
+  /**
+   * @async
+   * Get a group by their name.
+   * @param {string} name - the groups name
+   * @return {Group} the group
+   * @throws {NotInDBError} there is no group with this name
+   */
+  async getGroupByName(name: string): Promise<Group> {
+    const group = await this.groupRepository.findOne({
+      where: { name: name },
+    });
+    if (group === undefined) {
+      throw new NotInDBError(`Group with name '${name}' not found`);
+    }
+    return group;
+  }
+
+  /**
+   * Build GroupInfoDto from a group.
+   * @param {Group} group - the group to use
+   * @return {GroupInfoDto} the built GroupInfoDto
+   */
+  toGroupDto(group: Group | null | undefined): GroupInfoDto | null {
+    if (!group) {
+      this.logger.warn(`Recieved ${group} argument!`, 'toGroupDto');
+      return null;
+    }
+    return {
+      name: group.name,
+      displayName: group.displayName,
+      special: group.special,
+    };
+  }
+}