Webhook for Facebook with Subscriptions
The Problem
So, I need to record feed (comments, like, posts) from my Facebook Page and record it to my database.
I will need to use Facebook Graph API Real Time Updates for this.
Official documentation
https://developers.facebook.com/docs/graph-api/real-time-updates/v2.4
But as always, deciphering Facebook’s documentation is a form of art.
Create a Facebook application
You will need Facebook app ID and secret key to create a permanent token for the feed. This link will help you.
https://developers.facebook.com/docs
Add your app to your page’s subcribed apps
To receive live updates from your Facebook App, you will need to add your app to your page’s subcribed apps.
Refer to previous entry for steps
http://ukimiawz.github.io/facebook/2015/08/11/facebook-page-subscribed-apps/
Create a Callback URL
You will need to create a page in your server. This page will serve as a receiver for facebook JSON live updates. The tricky part is, this page will need to support both GET and POST request from facebook.
On subscribing, facebook will send a GET request to your callback url with several parameters.
hub.mode - The string "subscribe" is passed in this parameter
hub.challenge - A random string
hub.verify_token - The verify_token value you specified when you created the subscription
You will need to verify the token to make sure that it’s Facebook that made the requests.
You will also need to print out hub.challenge parameter value to your page.
In python :
request.args.get('hub.challenge', 'default-value')
Or just for testing, you can create a temporary callback url at RequestBin
http://requestb.in/
Send a Subscribe request to the page
Lastly, you will need to send POST request for the subscriptions
https://developers.facebook.com/docs/graph-api/reference/v2.4/app/subscriptions/
Using the Graph API Explorer might be the easiest way and the url format is
/{object-id}/subscriptions
This object-id is your page ID if you want to receive live updates from your page. You will need to send some parameters along the POST request
- object
Indicates the object type that this subscription applies to.
enum{user, page, permissions, payments}
- callback_url
The URL that will receive the POST request when an update is triggered.
string
- fields
The set of fields in this object that are subscribed to.
string[]
- active
Indicates whether or not the subscription is active.
bool
For the valid fields options, you can check more in here on Valid Fields for Subscription
https://developers.facebook.com/docs/graph-api/real-time-updates/v2.4
You can send several fields if you want to receive updates from several parts of the pages (name, description, etc) But I usually just use Feed.
Feed will sent you updates on your Facebook Page’s comments, likes, and new posts.