How to build a public Google Ads integration: Building the Auth Flow

Aug 1, 2024 • 5 minute read

Hey there, fellow JavaScript devs! Ready to dive into the world of Google Ads API integration? Let's focus on the most crucial part: building a rock-solid auth flow. Buckle up, because we're about to make your integration secure and user-friendly.

The Lowdown on Google Ads API

Google Ads API is a powerhouse for managing advertising campaigns programmatically. But before we can tap into its potential, we need to nail the authorization process. Trust me, getting this right will save you headaches down the road.

Before We Start Coding

Make sure you've got these ducks in a row:

A Google Cloud Console project (you've set this up, right?)
Your Client ID and Client Secret (keep these safe!)
Your favorite JavaScript OAuth library (I'm partial to google-auth-library)

OAuth 2.0: Your New Best Friend

We're using the Authorization Code Flow here. It's like a secret handshake between your app and Google, ensuring only the cool kids (your authorized users) get in.

For Google Ads, you'll want these scopes:

const SCOPES = ['https://www.googleapis.com/auth/adwords'];

Let's Build This Auth Flow!

Step 1: Craft that Authorization URL

const authUrl = oauth2Client.generateAuthUrl({
  access_type: 'offline',
  scope: SCOPES,
});

Send your users to this URL. They'll log in and grant permissions.

Step 2: Handle the Redirect Like a Pro

When Google sends the user back, grab that authorization code:

const { code } = req.query;

Step 3: Trade Code for Tokens

Exchange that code for the real treasure - access and refresh tokens:

const { tokens } = await oauth2Client.getToken(code);
oauth2Client.setCredentials(tokens);

Step 4: Stash Those Tokens

Store these securely. Your database, a secure cookie, wherever - just keep 'em safe!

Token Management: Keep the Party Going

Access tokens don't last forever. Be ready to refresh:

if (oauth2Client.isTokenExpiring()) {
  await oauth2Client.refreshAccessToken();
}

Making Authenticated Requests

Now you're ready to rock! Use your oauth2Client to make authenticated requests:

const ads = google.ads({
  version: 'v14',
  auth: oauth2Client,
});

const response = await ads.customers.list({
  // Your request parameters
});

Best Practices (Don't Skip This!)

Never, ever expose your Client Secret
Implement proper error handling
Respect Google's rate limits (they're there for a reason)

Troubleshooting Tips

Running into issues? Check out Google's OAuth 2.0 Playground. It's a lifesaver for debugging auth flows.

Wrapping Up

And there you have it! You've just built a solid auth flow for your Google Ads integration. Pat yourself on the back – you're well on your way to creating something awesome.

Want to Learn More?

Check out these resources:

Now go forth and build amazing things! Remember, the key to a great integration is a solid foundation, and you've just nailed it. Happy coding!