Python quickstart

Stay organized with collections Save and categorize content based on your preferences.

Quickstarts explain how to set up and run an app that calls a Google Workspace API.

Google Workspace quickstarts use the API client libraries to handle some details of the authentication and authorization flow. We recommend that you use the client libraries for your own apps. Before you can run the sample app, each quickstart requires that you turn on authentication and authorization. If you're unfamiliar with authentication and authorization for Google Workspace APIs, read the Authentication and authorization overview.

Create a Python command-line application that makes requests to the Drive API.

Objectives

  • Set up your environment.
  • Install the client library.
  • Set up the sample.
  • Run the sample.

Prerequisites

To run this quickstart, you need the following prerequisites:

  • A Google account with Google Drive enabled.

Set up your environment

To complete this quickstart, set up your environment.

Enable the API

Before using Google APIs, you need to turn them on in a Google Cloud project. You can turn on one or more APIs in a single Google Cloud project.

Authorize credentials for a desktop application

To authenticate as an end user and access user data in your app, you need to create one or more OAuth 2.0 Client IDs. A client ID is used to identify a single app to Google's OAuth servers. If your app runs on multiple platforms, you must create a separate client ID for each platform.
  1. In the Google Cloud console, go to Menu > APIs & Services > Credentials.

    Go to Credentials

  2. Click Create Credentials > OAuth client ID.
  3. Click Application type > Desktop app.
  4. In the Name field, type a name for the credential. This name is only shown in the Google Cloud console.
  5. Click Create. The OAuth client created screen appears, showing your new Client ID and Client secret.
  6. Click OK. The newly created credential appears under OAuth 2.0 Client IDs.
  7. Save the downloaded JSON file as credentials.json, and move the file to your working directory.

Install the Google client library

  • Install the Google client library for Python:

    pip install --upgrade google-api-python-client google-auth-httplib2 google-auth-oauthlib
    

Configure the sample

  1. In your working directory, create a file named quickstart.py.
  2. Include the following code in quickstart.py:

    drive/quickstart/quickstart.py
    from __future__ import print_function
    
    import os.path
    
    from google.auth.transport.requests import Request
    from google.oauth2.credentials import Credentials
    from google_auth_oauthlib.flow import InstalledAppFlow
    from googleapiclient.discovery import build
    from googleapiclient.errors import HttpError
    
    # If modifying these scopes, delete the file token.json.
    SCOPES = ['https://www.googleapis.com/auth/drive.metadata.readonly']
    
    
    def main():
        """Shows basic usage of the Drive v3 API.
        Prints the names and ids of the first 10 files the user has access to.
        """
        creds = None
        # The file token.json stores the user's access and refresh tokens, and is
        # created automatically when the authorization flow completes for the first
        # time.
        if os.path.exists('token.json'):
            creds = Credentials.from_authorized_user_file('token.json', SCOPES)
        # If there are no (valid) credentials available, let the user log in.
        if not creds or not creds.valid:
            if creds and creds.expired and creds.refresh_token:
                creds.refresh(Request())
            else:
                flow = InstalledAppFlow.from_client_secrets_file(
                    'credentials.json', SCOPES)
                creds = flow.run_local_server(port=0)
            # Save the credentials for the next run
            with open('token.json', 'w') as token:
                token.write(creds.to_json())
    
        try:
            service = build('drive', 'v3', credentials=creds)
    
            # Call the Drive v3 API
            results = service.files().list(
                pageSize=10, fields="nextPageToken, files(id, name)").execute()
            items = results.get('files', [])
    
            if not items:
                print('No files found.')
                return
            print('Files:')
            for item in items:
                print(u'{0} ({1})'.format(item['name'], item['id']))
        except HttpError as error:
            # TODO(developer) - Handle errors from drive API.
            print(f'An error occurred: {error}')
    
    
    if __name__ == '__main__':
        main()

Run the sample

  1. In your working directory, build and run the sample:

    python3 quickstart.py
    
  2. The first time you run the sample, it prompts you to authorize access:

    1. If you're not already signed in to your Google Account, you're prompted to sign in. If you're signed in to multiple accounts, select one account to use for authorization.
    2. Click Accept.

    Authorization information is stored in the file system, so the next time you run the sample code, you aren't prompted for authorization.

You have successfully created your first Python application that makes requests to the Drive API.

Next steps