refactor(nestjs): Implement users module

packages/server/src/modules/UsersModule/commands/InviteUser.service.ts

@@ -0,0 +1,149 @@
+import { Inject, Injectable } from '@nestjs/common';
+import * as uniqid from 'uniqid';
+import * as moment from 'moment';
+import {
+  IUserSendInviteDTO,
+  IUserInvitedEventPayload,
+  IUserInviteResendEventPayload,
+} from '../Users.types';
+import { ERRORS } from '../Users.constants';
+import { ServiceError } from '@/modules/Items/ServiceError';
+import { TenantModelProxy } from '@/modules/System/models/TenantBaseModel';
+import { TenantUser } from '@/modules/Tenancy/TenancyModels/models/TenantUser.model';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { events } from '@/common/events/events';
+import { Role } from '@/modules/Roles/models/Role.model';
+import { ModelObject } from 'objection';
+import { SendInviteUserDto } from '../dtos/InviteUser.dto';
+
+@Injectable()
+export class InviteTenantUserService {
+  constructor(
+    private readonly eventEmitter: EventEmitter2,
+
+    @Inject(TenantUser.name)
+    private readonly tenantUserModel: TenantModelProxy<typeof TenantUser>,
+
+    @Inject(Role.name)
+    private readonly roleModel: TenantModelProxy<typeof Role>,
+  ) {}
+
+  /**
+   * Sends invite mail to the given email from the given tenant and user.
+   * @param {string} email -
+   * @param {IUser} authorizedUser -
+   * @return {Promise<IUserInvite>}
+   */
+  public async sendInvite(sendInviteDTO: SendInviteUserDto): Promise<{
+    invitedUser: TenantUser;
+  }> {
+    // Get the given role or throw not found service error.
+    const role = await this.roleModel().query().findById(sendInviteDTO.roleId);
+
+    // Validates the given email not exists on the storage.
+    await this.validateUserEmailNotExists(sendInviteDTO.email);
+
+    // Generates a new invite token.
+    const inviteToken = uniqid();
+
+    // Creates and fetches a tenant user.
+    const user = await this.tenantUserModel().query().insertAndFetch({
+      email: sendInviteDTO.email,
+      roleId: sendInviteDTO.roleId,
+      active: true,
+      invitedAt: new Date(),
+    });
+    // Triggers `onUserSendInvite` event.
+    await this.eventEmitter.emitAsync(events.inviteUser.sendInvite, {
+      inviteToken,
+      user,
+    } as IUserInvitedEventPayload);
+
+    return { invitedUser: user };
+  }
+
+  /**
+   * Re-send user invite.
+   * @param {number} tenantId -
+   * @param {string} email -
+   * @return {Promise<{ invite: IUserInvite }>}
+   */
+  public async resendInvite(userId: number): Promise<{ user: ModelObject<TenantUser> }> {
+    // Retrieve the user by id or throw not found service error.
+    const user = await this.getUserByIdOrThrowError(userId);
+
+    // Validate the user is not invited recently.
+    this.validateUserInviteThrottle(user);
+
+    // Validate the given user is not accepted yet.
+    this.validateInviteUserNotAccept(user);
+
+    // Generates a new invite token.
+    const inviteToken = uniqid();
+
+    // Triggers `onUserSendInvite` event.
+    await this.eventEmitter.emitAsync(events.inviteUser.resendInvite, {
+      user,
+      inviteToken,
+    } as IUserInviteResendEventPayload);
+
+    return { user };
+  }
+
+  /**
+   * Validate the given user has no active invite token.
+   * @param {number} tenantId
+   * @param {number} userId - User id.
+   */
+  private validateInviteUserNotAccept = (user: ModelObject<TenantUser>) => {
+    // Throw the error if the one invite tokens is still active.
+    if (user.inviteAcceptedAt) {
+      throw new ServiceError(ERRORS.USER_RECENTLY_INVITED);
+    }
+  };
+
+  /**
+   * Validates user invite is not invited recently before specific time point.
+   * @param {ITenantUser} user
+   */
+  private validateUserInviteThrottle = (user: ModelObject<TenantUser>) => {
+    const PARSE_FORMAT = 'M/D/YYYY, H:mm:ss A';
+    const beforeTime = moment().subtract(5, 'minutes');
+
+    if (moment(user.invitedAt, PARSE_FORMAT).isAfter(beforeTime)) {
+      throw new ServiceError(ERRORS.USER_RECENTLY_INVITED);
+    }
+  };
+
+  /**
+   * Retrieve the given user by id or throw not found service error.
+   * @param {number} userId - User id.
+   */
+  private getUserByIdOrThrowError = async (
+    userId: number,
+  ): Promise<TenantUser> => {
+    // Retrieve the tenant user.
+    const user = await this.tenantUserModel().query().findById(userId);
+
+    // Throw if the user not found.
+    if (!user) {
+      throw new ServiceError(ERRORS.USER_NOT_FOUND);
+    }
+    return user;
+  };
+
+  /**
+   * Throws error in case the given user email not exists on the storage.
+   * @param {string} email
+   * @throws {ServiceError}
+   */
+  private async validateUserEmailNotExists(email: string): Promise<void> {
+    const foundUser = await this.tenantUserModel()
+      .query()
+      .findOne('email', email);
+
+    if (foundUser) {
+      throw new ServiceError(ERRORS.EMAIL_EXISTS);
+    }
+  }
+}