Quick Guide to Realtime Data in Google Slides without Webhooks

Aug 2, 2024 • 6 minute read

Hey there, fellow JavaScript devs! Ready to dive into the world of real-time data in Google Slides? Let's skip the webhook hassle and explore how we can use good ol' polling to keep our slides up-to-date. Buckle up!

Setting the Stage: Google Slides API

First things first, let's get that API set up. You probably know the drill, but just in case:

Head to the Google Cloud Console
Enable the Google Slides API
Grab your credentials

Once you've got that sorted, install the googleapis library:

npm install googleapis

Polling: The Unsung Hero

Alright, let's get our hands dirty with some polling action. Here's a basic structure to get us started:

function pollSlides(interval) {
  setInterval(async () => {
    try {
      const data = await fetchSlideData();
      updateUI(data);
    } catch (error) {
      console.error('Oops!', error);
    }
  }, interval);
}

Fetching the Goods: Google Slides API

Now, let's actually grab that slide data. We'll use the presentations.get endpoint:

const { google } = require('googleapis');

async function fetchSlideData() {
  const auth = new google.auth.GoogleAuth({
    // Your auth config here
  });
  const slides = google.slides({ version: 'v1', auth });
  
  const response = await slides.presentations.get({
    presentationId: 'YOUR_PRESENTATION_ID'
  });
  
  return response.data;
}

Parsing the Response: Where the Magic Happens

Got the data? Great! Let's make sense of it:

function parseSlideData(data) {
  const slides = data.slides.map(slide => ({
    id: slide.objectId,
    elements: slide.pageElements.map(element => ({
      type: element.shape ? 'shape' : 'image',
      text: element.shape?.text?.textElements
        .map(t => t.textRun?.content)
        .join('') || ''
    }))
  }));
  
  return slides;
}

Keeping it Fresh: Updating the UI

Time to show off that fresh data! Here's a quick React example:

function SlideViewer({ slides }) {
  return (
    <div>
      {slides.map(slide => (
        <div key={slide.id}>
          {slide.elements.map((element, index) => (
            <p key={index}>{element.text}</p>
          ))}
        </div>
      ))}
    </div>
  );
}

Optimizing Our Polling Game

Let's not hammer that API, shall we? Here's a simple exponential backoff:

let interval = 1000;
const maxInterval = 60000;

function pollWithBackoff() {
  setTimeout(async () => {
    try {
      const data = await fetchSlideData();
      updateUI(data);
      interval = 1000; // Reset on success
    } catch (error) {
      console.error('Uh-oh', error);
      interval = Math.min(interval * 2, maxInterval);
    }
    pollWithBackoff();
  }, interval);
}

Handling Hiccups: Error Handling and Retries

When things go south, we've got to be ready. Here's a basic retry mechanism:

async function fetchWithRetry(maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fetchSlideData();
    } catch (error) {
      if (i === maxRetries - 1) throw error;
      await new Promise(resolve => setTimeout(resolve, 1000 * Math.pow(2, i)));
    }
  }
}

Performance Boosters

Let's be smart about our API calls. A little caching goes a long way:

let lastData = null;

async function fetchAndUpdateIfChanged() {
  const newData = await fetchSlideData();
  if (JSON.stringify(newData) !== JSON.stringify(lastData)) {
    lastData = newData;
    updateUI(newData);
  }
}

Wrapping Up

And there you have it! We've covered the basics of polling the Google Slides API for real-time(ish) data. Remember, while polling is straightforward, it might not be the best fit for all scenarios. Keep an eye on your API usage and consider alternatives if you need true real-time updates.

Want to Learn More?

Check out these resources:

Now go forth and create some awesome, dynamic presentations! Happy coding! 🚀