Secure API Integrations with OAuth 2.0 Client Credentials Flow

import requests
import os

# Configuration
TOKEN_URL = os.getenv('OAUTH_TOKEN_URL', 'https://auth.example.com/oauth/token')
API_BASE_URL = os.getenv('API_BASE_URL', 'https://api.example.com')
CLIENT_ID = os.getenv('OAUTH_CLIENT_ID', 'your_client_id')
CLIENT_SECRET = os.getenv('OAUTH_CLIENT_SECRET', 'your_client_secret')
SCOPE = os.getenv('OAUTH_SCOPE', 'read write')

class OAuthClientCredentialsApi:
    def __init__(self):
        self._access_token = None
        self._token_expiry = 0 # Unix timestamp

    def _get_access_token(self):
        if self._access_token and self._token_expiry > time.time() + 60: # Refresh 1 min before expiry
            return self._access_token

        print("Refreshing OAuth token...")
        headers = {'Content-Type': 'application/x-www-form-urlencoded'}
        payload = {
            'grant_type': 'client_credentials',
            'client_id': CLIENT_ID,
            'client_secret': CLIENT_SECRET,
            'scope': SCOPE
        }
        try:
            response = requests.post(TOKEN_URL, headers=headers, data=payload)
            response.raise_for_status() # Raise an exception for HTTP errors
            token_data = response.json()
            self._access_token = token_data['access_token']
            self._token_expiry = time.time() + token_data.get('expires_in', 3600)
            return self._access_token
        except requests.exceptions.RequestException as e:
            print(f"Error getting OAuth token: {e}")
            raise

    def make_api_request(self, method, endpoint, **kwargs):
        access_token = self._get_access_token()
        headers = kwargs.pop('headers', {})
        headers['Authorization'] = f'Bearer {access_token}'
        
        url = f"{API_BASE_URL}{endpoint}"
        try:
            response = requests.request(method, url, headers=headers, **kwargs)
            response.raise_for_status()
            return response.json()
        except requests.exceptions.RequestException as e:
            print(f"Error making API request to {url}: {e}")
            raise

# Usage:
# import time
# api = OAuthClientCredentialsApi()
# try:
#     # Example GET request
#     data = api.make_api_request('GET', '/users')
#     print("Users:", data)

#     # Example POST request
#     # new_user = {'name': 'John Doe', 'email': '[email protected]'}
#     # created_user = api.make_api_request('POST', '/users', json=new_user)
#     # print("Created User:", created_user)
# except Exception as e:
#     print(f"API interaction failed: {e}")