Facebook has extended its Realtime Updates API to include page posts so developers can receive automatic notifications whenever a change happens on a page.
The Realtime Updates API allows developers to subscribe to changes in data so they don’t have to continuously poll Facebook’s servers. Previously, developers were pulling the latest information about pages down to their own servers and looking for changes on their end. The addition of Realtime Updates should reduce server calls and processing power, making apps more reliable and decreasing load times.
For example, when a developer subscribes to updates from a page, they will receive a notification when a user Likes or comments on a page post. Facebook also supports realtime updates for a page’s name, category, picture, check-ins and feed.
Whenever a subscribed change occurs, Facebook makes an HTTP Post request to a callback URL specified by the developer, with a list of changes. Apps will generally receive notification of the change within a couple of minutes of its occurrence.