zync-nest-library/libs/src/googleapi/google.service.ts

NestJS library with database backup and file upload utilities

import { IDriveFileQuery } from "./google.interface";

import { google } from "googleapis";
import axios from "axios";
const rootFolder = process.cwd();
export class GoogleApiService {
  private authClient: any;
  private credentials = require(`${rootFolder}/credentials.json`);

  constructor() {
    this.setClient();
  }

  private setClient(tokens?: string) {
    this.authClient = new google.auth.OAuth2(
      this.credentials.installed.client_id,
      this.credentials.installed.client_secret,
      this.credentials.installed.redirect_uris[0]
    );
    this.authClient.setCredentials({ access_token: tokens });
  }

  public getAuthUrl() {
    // Set the desired scope for accessing Drive API
    const scope = ["https://www.googleapis.com/auth/drive.readonly"];

    // Generate an authentication URL and prompt the user to visit it
    return this.authClient.generateAuthUrl({
      access_type: "offline",
      scope: scope,
    });
  }

  public async getAuthToken(code: string) {
    const { tokens } = await this.authClient.getToken(code);
    this.authClient.setCredentials(tokens);
    return tokens;
  }

  public async getFolders(query: IDriveFileQuery): Promise<any> {
    try {
      this.setClient(query.accessToken);
      const drive = google.drive({ version: "v3", auth: this.authClient });
      const response = await drive.files.list({
        q: `'${query.folderId}' in parents and mimeType = 'application/vnd.google-apps.folder'`,
        fields: "files(id, name)",
        pageSize: query.pageSize || 1000,
      });
      return response?.data?.files;
    } catch (error) {
      console.error("Error querying files:", error.message);
      throw error;
    }
  }

  public async downloadFiles(folderId: string, token: string) {
    this.setClient(token);

    const drive = google.drive({ version: "v3", auth: this.authClient });

    const { data } = await drive.files.list({
      q: `'${folderId}' in parents and mimeType contains 'image/'`,
      fields: "files(id, name)",
    });

    const files = [];
    for await (const file of data.files) {
      const response = await axios.get(
        `https://www.googleapis.com/drive/v3/files/${file.id}?alt=media`,
        {
          responseType: "stream",
          headers: {
            Authorization: `Bearer ${this.authClient.credentials.access_token}`,
          },
        }
      );

      files.push(response);
    }

    return files;
  }
}