The interface OAuthProvider is a part of our public API. It is the entry point to perform operations on OAuth providers (social networks).

Please refer to OAuth section for details about the configuration of eXo Platform which is necessary to use OAuth providers (Facebook, Google, Twitter) for authentication of users. Once a user is logged in (or his account is linked with OAuth provider), his access token is saved in eXo Platform IDM database as a part of his User Profile. Then it is possible to retrieve his OAuth access token via OAuthProvider interface and run its operations. It is also possible to revoke or validate existing access tokens or send request to obtain new access tokens with more scopes (privileges).

Retrieve an Instance of OAuthProvider

First, you need to retrieve the appropriate instance of OAuthProvider from Portal:

Portal portal = PortalRequest.getInstance().getPortal();

OAuthProvider facebookProvider = portal.getOAuthProvider(OAuthProvider.FACEBOOK)

Currently eXo Platform supports three OAuth providers:

OAuthProvider Operations

The following snippet shows some basic use of OAuthProvider API:

// Retrieve instance of Google OAuth provider

OAuthProvider googleProvider = PortalRequest.getInstance().getPortal().getOAuthProvider(OAuthProvider.GOOGLE);

 

// Check if Google was enabled in configuration.properties

if (googleProvider == null) {

    renderResp.getWriter().println("Authentication with Google not available. See OAuth section in Reference Guide for how to enable it");

    return;

}

 

// Retrieve the key and display name of the social network

String key = googleProvider.getKey();

String friendlyName = googleProvider.getFriendlyName();

renderResp.getWriter().println(friendlyName + " is enabled");

 

// Retrieve access token of the current user

AccessToken accessToken = googleProvider.loadAccessToken(renderReq.getRemoteUser());

 

// Check if access token is available. It's the case when this user was registered/authenticated into portal

// through Google+ or if he linked his account with Google+

if (accessToken == null) {

    renderResp.getWriter().println("Your account is not linked with Google+. You can link it in 'Social network' tab of " +

        "user settings or you can authenticate through Google into portal");

    return;

}

 

// Check if access token is valid and refresh it if necessary

try {

    accessToken = googleProvider.validateTokenAndUpdateScopes(accessToken);

} catch (OAuthApiException oauthException) {

    if (oauthException.getExceptionCode().equals(OAuthApiExceptionCode.ACCESS_TOKEN_ERROR)) {

        renderResp.getWriter().println("Your access token is invalid or has been revoked");

    } else if (oauthException.getExceptionCode().equals(OAuthApiExceptionCode.IO_ERROR)) {

        renderResp.getWriter().println("Network error during the communication with Google");

    }

}

 

// Check all available scopes

String availableScopes = accessToken.getAvailableScopes();

 

// Check if we have scope to call Google+ operations

if (!availableScopes.contains("https://www.googleapis.com/auth/plus.login")) {

    // Redirect to Google+ and ask for plus.login scope

    googleProvider.startOAuthWorkflow("https://www.googleapis.com/auth/plus.login");

    return;

}

 

// Obtain Google API object to call Google plus API operations

Plus service = googleProvider.getAuthorizedSocialApiObject(accessToken, Plus.class);

 

// Retrieve activities from Google+ wall of user

ActivityFeed activityFeed = service.activities().list("me", "public").execute();

for (Activity activity : activityFeed.getItems()) {

    renderResp.getWriter().println(activity.getTitle());

}

 

// Revoke the access token. It won't be possible to run any operations with it anymore.

// And your application will be cleared from Google applications of current user on page https://plus.google.com/apps

googleProvider.revokeToken(accessToken);

 

// Remove the token from the UserProfile of the current user

googleProvider.removeAccessToken(request.getRemoteUser());

Access to Provider-Specific Operations

Method

<!-- <br/> --><span class="java_plain">oauthProvider</span><!-- <br/> --><span class="java_separator">.</span><!-- <br/> --><span class="java_plain">getAuthorizedSocialApiObject</span><!-- <br/> --><span class="java_separator">()</span>

is useful for obtaining access to provider-specific operations. This method usually returns objects from a 3rd party library. Those objects are always initialized with access token of the current user and can be used to retrieve data from the related social network.