How to build a public PDF.co integration: Building the Auth Flow

Introduction

Hey there, fellow JavaScript enthusiast! Ready to dive into the world of PDF.co integrations? Today, we're going to tackle one of the most crucial aspects of building a public integration: the authorization flow. PDF.co's powerful API is at your fingertips, but first, we need to make sure our users can securely access it. Let's get started!

Prerequisites

Before we jump in, make sure you've got:

• A PDF.co account and API key (if you don't have one, go grab it!)
• Node.js and npm installed on your machine
• A basic understanding of OAuth 2.0 (don't worry, we'll cover the essentials)

Setting up the project

Alright, let's get our hands dirty! First things first:

mkdir pdf-co-integration
cd pdf-co-integration
npm init -y
npm install express axios dotenv

Great! We've got our project set up with the necessary dependencies.

Configuring the environment

Security first! Let's keep those sensitive details safe:

touch .env

Open up that .env file and add:

PDF_CO_API_KEY=your_api_key_here
PDF_CO_CLIENT_ID=your_client_id_here
PDF_CO_CLIENT_SECRET=your_client_secret_here

Don't forget to add .env to your .gitignore file!

Implementing the authorization flow

Now for the fun part! Let's build out our auth flow:

const express = require('express');
const axios = require('axios');
require('dotenv').config();

const app = express();

app.get('/auth', (req, res) => {
  const authUrl = `https://api.pdf.co/oauth2/authorize?client_id=${process.env.PDF_CO_CLIENT_ID}&response_type=code&redirect_uri=http://localhost:3000/callback`;
  res.redirect(authUrl);
});

app.get('/callback', async (req, res) => {
  const { code } = req.query;
  try {
    const response = await axios.post('https://api.pdf.co/oauth2/token', {
      grant_type: 'authorization_code',
      code,
      client_id: process.env.PDF_CO_CLIENT_ID,
      client_secret: process.env.PDF_CO_CLIENT_SECRET,
      redirect_uri: 'http://localhost:3000/callback'
    });
    const { access_token, refresh_token } = response.data;
    // Store these tokens securely (more on this later)
    res.send('Authorization successful!');
  } catch (error) {
    console.error('Error during token exchange:', error);
    res.status(500).send('Authorization failed');
  }
});

app.listen(3000, () => console.log('Server running on port 3000'));

Storing and managing tokens

Now that we've got our tokens, we need to keep them safe and fresh:

// Add this to your existing code
let accessToken = null;
let refreshToken = null;

function storeTokens(access, refresh) {
  accessToken = access;
  refreshToken = refresh;
  // In a real app, you'd want to store these more securely
}

async function refreshAccessToken() {
  try {
    const response = await axios.post('https://api.pdf.co/oauth2/token', {
      grant_type: 'refresh_token',
      refresh_token: refreshToken,
      client_id: process.env.PDF_CO_CLIENT_ID,
      client_secret: process.env.PDF_CO_CLIENT_SECRET
    });
    storeTokens(response.data.access_token, response.data.refresh_token);
  } catch (error) {
    console.error('Error refreshing token:', error);
  }
}

Making authenticated requests to PDF.co API

Time to put those tokens to work:

async function makeApiRequest(endpoint, data) {
  try {
    const response = await axios.post(`https://api.pdf.co/v1/${endpoint}`, data, {
      headers: { Authorization: `Bearer ${accessToken}` }
    });
    return response.data;
  } catch (error) {
    if (error.response && error.response.status === 401) {
      await refreshAccessToken();
      return makeApiRequest(endpoint, data); // Retry with new token
    }
    throw error;
  }
}

Best practices and security considerations

Remember, security is key! Always:

• Use HTTPS in production
• Implement CSRF protection
• Store tokens securely (consider using encryption or a secure token storage solution)

Testing the integration

Let's make sure everything's working:

app.get('/test', async (req, res) => {
  try {
    const result = await makeApiRequest('pdf/info', { url: 'https://example.com/sample.pdf' });
    res.json(result);
  } catch (error) {
    res.status(500).json({ error: 'API request failed' });
  }
});

Conclusion

And there you have it! You've just built a secure authorization flow for your PDF.co integration. Pretty cool, right? From here, you can expand your integration to leverage all the awesome features PDF.co has to offer.

Additional resources

Want to dive deeper? Check out:

• PDF.co API Documentation
• OAuth 2.0 Specification

Happy coding, and may your PDFs always be perfectly processed! 🚀📄