Google App Engine and the Google+ API

I've been playing with what the Google+ API has to offer and I've found it quite easy to integrate into my Google App Engine apps using the google-api-java-client.

I initially followed the Quick start for Java tutorial with regard to creating the OAuth tokens and so forth, but the google-api-java-client has some good tutorials regarding making the actual OAuth calls. See for example this section about how to make the calls from a Google App Engine app. The library handles all the plumbing for you.

I only had to make one ammendment to their example. I found that the refresh token wasn't being returned along with the access token after it was granted. However this was simply fixed by adding a call to setApprovalPrompt("force") on the GoogleAuthorizationCodeFlow.Builder, like so:

public static GoogleAuthorizationCodeFlow newFlow() throws IOException {
    return new GoogleAuthorizationCodeFlow.Builder(HTTP_TRANSPORT, JSON_FACTORY,
            getClientCredential(),             Collections.singleton(PlusScopes.ME.getUri())).setCredentialStore(
            new AppEngineCredentialStore()).setAccessType("offline")
Posted on March 18, 2013 and filed under dev.