Mastering Authentication with Requests OAuthlib for Python Developers

The Requests-OAuthlib library is a versatile tool designed to simplify the process of connecting Python applications to third-party APIs that use OAuth for authorization. With seamless integration of the requests library and OAuth working together, it offers a user-friendly interface to handle OAuth 1 and OAuth 2 tokens. Whether you’re integrating with APIs like Google, Twitter, or GitHub, this library streamlines token management and API authentication.

In this blog post, we’ll dive deep into “requests-oauthlib”, learn how to authenticate with OAuth 1 and OAuth 2, and explore step-by-step coding examples of using this library with the APIs. Let’s also build a practical application example at the end!

Installing Requests-OAuthlib

Before we get started, you need to install the library:

  pip install requests-oauthlib

Authenticating with OAuth 1

OAuth 1 is commonly used for older APIs like Twitter. Here’s an example of accessing a resource using OAuth 1:

  from requests_oauthlib import OAuth1Session

  # Replace the below values with your credentials
  consumer_key = "your_consumer_key"
  consumer_secret = "your_consumer_secret"
  access_token = "your_access_token"
  access_token_secret = "your_access_token_secret"

  # Create an OAuth1Session
  oauth = OAuth1Session(
      consumer_key,
      client_secret=consumer_secret,
      resource_owner_key=access_token,
      resource_owner_secret=access_token_secret
  )

  # Access a protected resource
  response = oauth.get('https://api.twitter.com/1.1/statuses/user_timeline.json')
  print(response.json())

Authenticating with OAuth 2

OAuth 2 is simpler and used by most modern APIs. Here’s an example of using the library with OAuth 2:

  from requests_oauthlib import OAuth2Session

  client_id = "your_client_id"
  client_secret = "your_client_secret"
  authorization_base_url = 'https://provider.com/oauth/authorize'
  token_url = 'https://provider.com/oauth/token'

  # Redirect user to provider for authorization
  oauth = OAuth2Session(client_id)
  authorization_url, state = oauth.authorization_url(authorization_base_url)
  print('Please go to %s and authorize access.' % authorization_url)

  # Get the authorization response URL from the user
  redirect_response = input('Paste the full redirect URL here: ')

  # Fetch the access token
  token = oauth.fetch_token(
      token_url,
      authorization_response=redirect_response,
      client_secret=client_secret
  )

  # Access protected resources
  response = oauth.get('https://provider.com/api/resource')
  print(response.json())

Using Refresh Tokens

Some OAuth 2 workflows provide refresh tokens to keep your access scope active. Here’s how to use them:

  token = {
      'access_token': 'existing_access_token',
      'refresh_token': 'your_refresh_token',
      'token_type': 'Bearer',
      'expires_in': '-30'  # Simulate expired token
  }

  extra = {
      'client_id': client_id,
      'client_secret': client_secret,
  }

  # Auto-refreshing token functionality
  oauth = OAuth2Session(client_id, token=token, auto_refresh_kwargs=extra,
                        auto_refresh_url=token_url, token_updater=lambda x: None)

  # Access protected resources
  response = oauth.get('https://provider.com/api/resource')
  print(response.json())

A Practical Application Example

Let’s create a real-world example: a GitHub Repository Lister. This app will authenticate with GitHub using OAuth 2 and fetch repositories for the authenticated user.

  from requests_oauthlib import OAuth2Session

  CLIENT_ID = 'your_github_app_client_id'
  CLIENT_SECRET = 'your_github_app_client_secret'
  AUTH_URL = 'https://github.com/login/oauth/authorize'
  TOKEN_URL = 'https://github.com/login/oauth/access_token'

  # Step 1: Redirect user to authorize the app
  github = OAuth2Session(CLIENT_ID)
  authorization_url, _ = github.authorization_url(AUTH_URL)
  print(f'Please go to {authorization_url} and authorize access.')

  # Step 2: Receive the callback from the user
  redirect_response = input('Paste the full redirect URL here: ')

  # Step 3: Retrieve the access token
  token = github.fetch_token(
      TOKEN_URL,
      authorization_response=redirect_response,
      client_secret=CLIENT_SECRET
  )

  # Step 4: Fetch user's repositories
  response = github.get('https://api.github.com/user/repos')
  repos = response.json()

  print('Your Repositories:')
  for repo in repos:
      print(f"- {repo['name']}: {repo['html_url']}")

The Requests-OAuthlib library provides convenience when dealing with complicated OAuth workflows. Whether you’re accessing APIs for personal projects or professional applications, mastering this library ensures you secure data seamlessly and efficiently.