Securely Authenticate API Requests with OAuth 2.0 Client Credentials Flow

const axios = require('axios');

// Configuration for your OAuth client
const TOKEN_URL = 'https://your-auth-server.com/oauth/token';
const API_URL = 'https://your-resource-server.com/api/data';
const CLIENT_ID = process.env.OAUTH_CLIENT_ID;
const CLIENT_SECRET = process.env.OAUTH_CLIENT_SECRET;
const SCOPES = 'read:data write:data'; // Request necessary scopes

async function getAccessToken() {
  try {
    const response = await axios.post(
      TOKEN_URL,
      new URLSearchParams({
        grant_type: 'client_credentials',
        scope: SCOPES,
        client_id: CLIENT_ID,
        client_secret: CLIENT_SECRET,
      }).toString(),
      {
        headers: {
          'Content-Type': 'application/x-www-form-urlencoded',
        },
      }
    );
    return response.data.access_token;
  } catch (error) {
    console.error('Error fetching access token:', error.response ? error.response.data : error.message);
    throw new Error('Failed to obtain access token.');
  }
}

async function fetchDataWithAccessToken(accessToken) {
  try {
    const response = await axios.get(API_URL, {
      headers: {
        Authorization: `Bearer ${accessToken}`,
      },
    });
    return response.data;
  } catch (error) {
    console.error('Error fetching data:', error.response ? error.response.data : error.message);
    throw new Error('Failed to fetch data with access token.');
  }
}

// Example usage
(async () => {
  if (!CLIENT_ID || !CLIENT_SECRET) {
    console.error('OAUTH_CLIENT_ID and OAUTH_CLIENT_SECRET environment variables must be set.');
    return;
  }
  try {
    const accessToken = await getAccessToken();
    console.log('Access Token obtained:', accessToken.substring(0, 10) + '...'); // Log first 10 chars
    const apiData = await fetchDataWithAccessToken(accessToken);
    console.log('API Data:', apiData);
  } catch (error) {
    console.error('Integration failed:', error.message);
  }
})();