Quick Guide to Realtime Data in Google Contacts without Webhooks

Aug 1, 2024 • 8 minute read

Hey there, fellow JavaScript aficionados! Ready to dive into the world of real-time Google Contacts data without the luxury of webhooks? Buckle up, because we're about to embark on a polling adventure that'll keep your user-facing integration fresh and snappy.

The Lowdown on Google Contacts and Real-time Data

So, you want to keep your app's contact data in sync with Google Contacts? Awesome! But wait, no webhooks? No problem! We're going to tackle this with good old-fashioned polling, and I promise it'll be smoother than you think.

Setting Up the Google Contacts API

First things first, let's get you set up with the Google Contacts API. I'm not going to bore you with the nitty-gritty (you're pros, after all), so here's the TL;DR:

Head to the Google Cloud Console
Create a new project (or select an existing one)
Enable the Google People API (that's the one for Contacts)
Create credentials (OAuth 2.0 Client ID for web application)

For the full monty, check out Google's official docs.

Polling Like a Pro

Alright, let's get to the meat of it. Here's a basic polling structure to get you started:

async function pollGoogleContacts() {
  while (true) {
    try {
      const contacts = await fetchGoogleContacts();
      updateLocalContacts(contacts);
      await new Promise(resolve => setTimeout(resolve, 60000)); // Poll every minute
    } catch (error) {
      console.error('Polling error:', error);
      await new Promise(resolve => setTimeout(resolve, 5000)); // Wait 5 seconds before retrying
    }
  }
}

Simple, right? But hold your horses, we're just getting started.

Supercharging Your Polling with syncToken

Want to make your polling more efficient? Enter the syncToken. This nifty little token helps you fetch only the changes since your last sync. Here's how to use it:

let syncToken = null;

async function fetchGoogleContacts() {
  const options = {
    personFields: 'names,emailAddresses,phoneNumbers',
    syncToken: syncToken
  };
  
  const response = await gapi.client.people.people.connections.list({
    resourceName: 'people/me',
    ...options
  });
  
  syncToken = response.result.nextSyncToken;
  return response.result.connections;
}

Dealing with Rate Limits Like a Champ

Google's not going to let you hammer their API endlessly. Let's implement some exponential backoff to play nice:

async function pollWithBackoff() {
  let backoffTime = 1000;
  while (true) {
    try {
      await fetchGoogleContacts();
      backoffTime = 1000; // Reset on success
    } catch (error) {
      if (error.status === 429) { // Too Many Requests
        await new Promise(resolve => setTimeout(resolve, backoffTime));
        backoffTime *= 2; // Exponential backoff
      } else {
        console.error('Error:', error);
        await new Promise(resolve => setTimeout(resolve, 5000));
      }
    }
  }
}

Processing Data Like a Boss

Now that you're fetching data efficiently, let's process it smartly:

function updateLocalContacts(contacts) {
  contacts.forEach(contact => {
    const localContact = findOrCreateLocalContact(contact.resourceName);
    localContact.name = contact.names?.[0]?.displayName || '';
    localContact.email = contact.emailAddresses?.[0]?.value || '';
    localContact.phone = contact.phoneNumbers?.[0]?.value || '';
    saveLocalContact(localContact);
  });
}

Keeping Users Happy

Remember, your users want fresh data, but they also want a snappy app. Here's a neat trick to give them the best of both worlds:

let lastPollTime = 0;
const POLL_INTERVAL = 60000; // 1 minute

async function getUserContacts() {
  const now = Date.now();
  if (now - lastPollTime > POLL_INTERVAL) {
    await pollGoogleContacts();
    lastPollTime = now;
  }
  return getLocalContacts();
}

function forceRefresh() {
  lastPollTime = 0;
  return getUserContacts();
}

When Things Go South: Error Handling and Logging

Even the best-laid plans can go awry. Let's make sure we're prepared:

async function pollGoogleContacts() {
  try {
    const contacts = await fetchGoogleContacts();
    updateLocalContacts(contacts);
    console.log('Successfully synced contacts');
  } catch (error) {
    console.error('Error syncing contacts:', error);
    // You might want to send this to your error tracking service
    Sentry.captureException(error);
  }
}

Turbocharging Performance

Let's squeeze out some extra performance with a simple caching strategy:

const cache = new Map();

function getCachedContact(id) {
  if (cache.has(id)) {
    const { contact, timestamp } = cache.get(id);
    if (Date.now() - timestamp < 300000) { // 5 minutes cache
      return contact;
    }
  }
  return null;
}

function setCachedContact(id, contact) {
  cache.set(id, { contact, timestamp: Date.now() });
}

Wrapping It Up

And there you have it, folks! You're now equipped to create a robust, efficient, and user-friendly Google Contacts integration without relying on webhooks. Remember, polling might seem old school, but with these optimizations, it can be just as effective for most use cases.

As you scale up, keep an eye on your API usage, consider implementing more advanced caching strategies, and always be on the lookout for ways to improve performance.

Happy coding, and may your contacts always be in sync!