The main aim of this application is to go familiar with the Google Plus API usage. Google Plus provides an extremely easy to use API to access the public contents on it. Here we will create a simple search application to search user profiles on Google Plus.

Complete code is provided in the post (PHP) and instructions on setting up an "application" on G+ so you can get the keys needed to connect to the API. You can see it in action in the live demo or just download the source to get started.

I've written about Google and OAuth before, but that was OAuth v1.0, and they are introducing OAuth2 for their newer APIs; in this example I was identifying myself in order to use the Google Plus API. [...] OAuth 2 doesn't need an extension or any particular library as it doesn't have the signing component that OAuth 1 had, and OAuth 2 also has fewer round trips. It does require SSL however, because the requests are in the clear.

She includes some code snippets with an example of a connection - making a request to the remote HTTPS resource, adding some parameters to the URL (including the response type, your client ID and a redirect url). The response then contains the "code" value you'll need to make the second request to fetch the access token you'll need on future requests. You can find out more about the interface she's accessing in these docs about the Google Plus API.

Google+ recently releases to developers the first version of its Api, which focuses on public data about profiles and their activities: status updates, resharings and links. I dived into the Api and wrote a small sample application to get a feel of how easy is to get started, and what can we do with the Api for now. All the code is at the bottom of this post.

He goes through the steps you'll need to get set up - registering an application, getting a library to help make the connection (here's a PHP one) and configuring it with your credentials. You can get "People" and "Activities" information from the API. He shows some sample output for each - basic user information (nested arrays) and some of his activities (again, nested arrays). He includes the source for his sample application that pulls a user's profile information and lists out their latest (public) activities.