How to build a public Adobe Sign integration: Building the Auth Flow

Hey there, fellow JavaScript developer! Ready to dive into the world of Adobe Sign integration? Let's focus on the most crucial part: building a rock-solid authorization flow. Buckle up, because we're about to make your integration secure and user-friendly in no time.

Introduction

Adobe Sign is a powerhouse for managing digital signatures, and integrating it into your app can be a game-changer. But before we can start sending documents for signing, we need to tackle the authorization flow. It's the gatekeeper that ensures only the right users can access your integration. Let's make it happen!

Prerequisites

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

• An Adobe Developer Console account (if you don't have one, go grab it!)
• A basic understanding of OAuth 2.0 (don't worry, we'll refresh your memory)
• A Node.js and Express.js setup ready to go

Got all that? Great! Let's move on to the fun stuff.

Setting up the Adobe Sign API

First things first, let's get you set up with Adobe Sign:

1. Head over to the Adobe Developer Console and create a new integration.
2. Choose "Adobe Sign API" and follow the prompts.
3. Once you're done, you'll get a client ID and client secret. Guard these with your life!

Implementing the Authorization Flow

Now, let's build this flow step by step:

Initiating the auth request

We'll start by constructing the authorization URL:

const authUrl = `https://secure.adobe.com/oauth/authorize?response_type=code&client_id=${clientId}&redirect_uri=${redirectUri}&scope=user_login:self+agreement_send:account`;

When a user wants to connect their Adobe Sign account, redirect them to this URL:

res.redirect(authUrl);

Handling the callback

After the user logs in, Adobe will redirect them back to your redirect_uri with an authorization code. Let's catch that:

app.get('/callback', async (req, res) => {
  const { code } = req.query;
  // Exchange this code for tokens
});

Now, let's exchange that code for access and refresh tokens:

const tokenResponse = await axios.post('https://api.adobe.com/oauth/token', {
  grant_type: 'authorization_code',
  client_id: clientId,
  client_secret: clientSecret,
  code: code,
  redirect_uri: redirectUri
});

const { access_token, refresh_token } = tokenResponse.data;

Store these tokens securely. Please, for the love of all that is holy, don't just stick them in a text file!

Token Management

Access tokens don't last forever, so let's set up a refresh mechanism:

async function refreshAccessToken(refreshToken) {
  const response = await axios.post('https://api.adobe.com/oauth/token', {
    grant_type: 'refresh_token',
    client_id: clientId,
    client_secret: clientSecret,
    refresh_token: refreshToken
  });
  
  return response.data.access_token;
}

Use this function when you detect that your access token has expired. Speaking of which, always check for 401 errors in your API responses – that's your cue to refresh!

Making Authenticated Requests

Now that you've got your access token, using it is a breeze:

const response = await axios.get('https://api.adobe.com/api/rest/v6/agreements', {
  headers: {
    Authorization: `Bearer ${accessToken}`
  }
});

If you get a 401, you know what to do – refresh that token!

Best Practices

A few quick tips to keep your integration smooth and secure:

• Never, ever expose your client secret on the client-side.
• Use HTTPS everywhere. No exceptions!
• Implement rate limiting to play nice with Adobe's API.
• Store tokens securely, preferably encrypted.

Conclusion

And there you have it! You've just built a solid authorization flow for your Adobe Sign integration. With this in place, you're ready to start sending documents, collecting signatures, and looking like a digital paperwork wizard.

Remember, this is just the beginning. There's a whole world of Adobe Sign API features waiting for you to explore. So go forth and integrate!

Resources

Want to dive deeper? Check out these resources:

• Adobe Sign API documentation
• OAuth 2.0 RFC

Happy coding, and may your integrations be ever secure and your tokens always fresh!