Google+ API is finally released. This initial API release is focused on public data only (it lets you read information that people have shared publicly on Google+).

Google+ API methods are RESTful HTTP requests which return JSON responses and it uses OAuth 2 for secure trusted access to user data.

Here are some sample codes from the Google’s blog post:

GET https://www.googleapis.com/plus/v1/people/108189587050871927619?key=yourAPIKey

And it will return:

{
	"kind": "plus#person",
	"id": "108189587050871927619",
	"displayName": "Chris Chabot",
	"image": {
		"url": "https://lh5.googleusercontent.com/-cQNLOQzkGpE/AAAAAAAAAAI/AAAAAAAAEjo/M9_pXL-ra4Q/photo.jpg"
	},
	"organizations":
	[
		{
			"name": "Google+ Developer Relations",
			"title": "Developer Advocate & Manager",
			"type": "work"
		}
	]
}

Check out the new Google+ Developer Website at developers.google.com/+/ for more information. There are also a few beta libraries already available (.NET, GWT, Java, Objective C, PHP, Python & Ruby) from Google.

Official Site: Google+ Developer Site
Official Blog Post: Getting Started on the Google+ API