JavaOne: Creating Serverside and Mobile Mashups with the OpenSocial Java client libraries

Creating Server-Side andMobile Mashups withOpenSocial's JavaTM ClientLibraries

Chris SchalkRyan BoydGoogleJavaOne 2009

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Agenda

> OpenSocial Background/Overview> OpenSocial REST support> Introducing the REST client libraries> OpenSocial Authorization - OAuth> Using the OpenSocial Java client library> Building Server-Side Mashups> Building Mobile Mashups> Summary

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Agenda


What is OpenSocial?

“OpenSocial defines a common set of APIs based onOpen Standards for building social applications acrossmultiple websites”

What is OpenSocial?

Before OpenSocial…

What is OpenSocial?

Standards Based!

What is OpenSocial?

Learn once… Write anywhere

Who owns OpenSocial?

OpenSocial is managed under the auspices of the“OpenSocial Foundation” - http://www.opensocial.org

No!?

Who’s Using it?

And many more…

OpenSocial now has over 800 Million users

Demonstration

> A simple OpenSocial gadget demonstration

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Agenda


The Evolution of the OpenSocial RESTSpecification

> Before v. 0.8, the only OpenSocial API was aJavaScript API Only worked within gadgets

> Initial OpenSocial API did not have a RESTSpecification. No server-to-server communication No options for Desktop or Mobile integration

Lack of REST support meant no server-side integration> Through OpenSocial’s open specification process,

the community responded and created theOpenSocial REST specification

OpenSocial REST support rolls out

> Version 0.8.1 RESTful and RPC protocols established

RPC protocol responds to HTTP POSTs and allows forbatching of requests

Server responded to REST requests in either XML orJSON

AtomPub operations supported

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OpenSocial REST Support

Opens new development models

• Server-to-server communication

• Multiple client types

• Server based UIs (JSP/JSF)

• Mobile devices

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RESTful Protocol• Resources are URLs.

/people/{guid}/@all

• All people connected to the given user:Example - People:

/people/{guid}/@friends

• All friends of the given user:

/people/{guid}/@self

• Profile of the given user:

/people/@me/@self

• Profile of the authenticated user:

/people/@supportedFields

• Supported Person fields:

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• Request extra fields

• Filtering:

• Paging:

fields={-join|,|field}.

filterBy={fieldname}filterOp={operation}filterValue={value}updatedSince={xsdDateTime}networkDistance={networkDistance}

count={count} sortBy={fieldname}sortOrder={order}startIndex={startIndex}

format={format}

RPC Protocol• Http POST instead of GET

Demonstration

> Experimenting with the the RESTful protocol withlocal Apache Shindig and a browser

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Agenda


OpenSocial Client Libraries

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A set of client libraries for thatenable direct communication toan OpenSocial server.

• Client libraries exist for PHP, Ruby, Python and Java• Supports both REST and RPC protocols• Documentation Wiki pages• Sample applications provided

OpenSocial Client Libraries

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http://code.google.com/p/opensocial-php-clienthttp://code.google.com/p/opensocial-ruby-clienthttp://code.google.com/p/opensocial-python-clienthttp://code.google.com/p/opensocial-objc-clienthttp://code.google.com/p/opensocial-java-client

Hosted on Google code projects

Demonstration

> Getting familiar with the OpenSocial Java clientlibrary

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Agenda


What about authorization?

> OAuth to the rescue!

> “An open protocol to allow secure APIauthorization in a simple and standard methodfrom desktop and web applications” - Oauth.net

> The OpenSocial Client Libraries offer built-insupport for OAuth

The OAuth Authorization Process Also known as “3-legged OAuth”

WebDesktopMobile

Application

OAuth Provider

SecuredResource

1. HTTP Request for unauthorized token

2. Response with with unauthorized token

3. Authorization Request for request token

7. HTTP Request for access token

9. Request for secured resource with access token

6. Redirect with authorized token

8. Response with with access token

4. Redirect forAccess consent

5. User choice accept/deny access

10. Response with requested data

Access ConsentPage

2-legged vs. 3-legged OAuth

> “2-legged” OAuth End-user installs a social network application, which authorizes app developer to

have access to their data App developer is given a consumer key and consumer secret to access the data of

any user who has installed their app, without any additional authorization Access is revoked by the end-user when they remove the app

> “3-legged” OAuth End-user is using native app or web app and hasn’t necessarily installed an app by

the same developer on the SNS If necessary, end-user is asked to authenticate to data provider End-user is sent to a webpage to authorize access to their data After authorization is granted, end-user returns to the app Access can sometimes be revoked by the end-user using an account

settings/preferences page

> The OpenSocial client libraries support both authorization types. Not all OpenSocial containers support both authorization types however.

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Agenda


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Fetching Data from an OpenSocial container Using “2-legged OAuth”

OpenSocialClient c = new OpenSocialClient(OpenSocialProvider.valueOf("ORKUT_SANDBOX"));

c.setProperty(OpenSocialClient.Property.CONSUMER_SECRET, "uynAeXiWTisflWX99KU1D2q5"); c.setProperty(OpenSocialClient.Property.CONSUMER_KEY, "orkut.com:623061448914"); c.setProperty(OpenSocialClient.Property.VIEWER_ID, "03067092798963641994");

try { // Retrieve the friends of the specified user using the OpenSocialClient Collection<OpenSocialPerson> friends = c.fetchFriends();

for (OpenSocialPerson friend : friends) { System.out.println("- " + friend.getDisplayName()); } } catch (org.opensocial.client.OpenSocialRequestException e) { System.out.println("OpenSocialRequestException thrown: " + e.getMessage()); e.printStackTrace(); }

Demonstration

> A 2-legged OAuth transaction using the Javaclient library. Requesting profile information and friends list from

orkut.com

Demonstration

> A 3-legged OAuth transaction example. Doing the “dance” with MySpace.com Using JSPs to show passing user to authorization

page

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Agenda

> OpenSocial Background/Overview> OpenSocial REST support> Introducing the REST client libraries> OpenSocial Authorization - Oauth> Using the OpenSocial Java client library> Building Server-Side Mashups> Building Mobile Mashups> Summary

Building Server-Side Mashups with the OpenSocial client libraries

> Any server-side Java Web application can easilyintegrate with an OpenSocial server

> An example: A aviation themed website with social features

enabled via the client libraries App uses Java App Engine Connects to Google Friend Connect which is an

OpenSocial container that supports 2-legged OAuth.

Demonstration

> Examining the “Plane Crazy” demo site.

Plane Crazy getGFCProfileInfo()

final OpenSocialProvider provider = OpenSocialProvider.valueOf("FRIENDCONNECT");final OpenSocialClient client = new OpenSocialClient(provider);

OpenSocialPerson person; try { person = client.fetchPerson(); session.setAttribute("gfcid", person.getId()); session.setAttribute("displayname", person.getDisplayName()); session.setAttribute("thumbnailurl", person.getThumbnailUrl()); session.setAttribute("GFCUser", "yes"); }...

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Agenda

> OpenSocial Background/Overview> OpenSocial REST support> Introducing the REST client libraries> OpenSocial Authorization - Oauth> Using the OpenSocial Java client library> Building Server-Side Mashups> Building Mobile Mashups> Summary

Building Mobile Mashups with the OpenSocial client libraries

> Any native mobile phone applications that cansupport OAuth and the REST protocol cancommunicate with an OpenSocial container

> For Java, this is easy. The OpenSocial Java client library comes with a

ready-to-run Android sample application whichdemonstrates extracting contact info from Plaxousing 3-legged OAuth.

Demonstration

> A simple 3-legged OAuth demonstration from amobile phone. Accessing Plaxo contacts info from an Android

phone.

REST

Building Mobile Mashups a more advanced Mobile example

> How an existing mobile game was made socialwith OpenSocial and the REST client libraries

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Demonstration

> The Social divide and conquer game!

Divide and Conquer step-by-step

Divide and Conquer selecting a social network

Divide and Conquer onDialogClosed()

token = OpenSocialOAuthClient.getRequestToken( client, provider);persistRequestToken(token, providerString);String url = OpenSocialOAuthClient. getAuthorizationUrl(provider, token, ANDROID_SCHEME + "://opensocial");

// Browse to webpageIntent i = new Intent(Intent.ACTION_VIEW);i.setData(Uri.parse(url));getContext().startActivity(i);

Divide and Conquer in the background

Divide and Conquer getTopScoreList()

ArrayList<Hashtable<String,String>> returnList = null;List<Object> args = new ArrayList<Object>();args.add("GetTopScores");try { returnList = getScoreInfoFromJson(callBackendRPC(args));} catch (Exception ex) { ex.printStackTrace();}return returnList;

Divide and Conquer getSelfAndFriends()

friends = c.fetchFriends();self = c.fetchPerson();

for (OpenSocialPerson person : friends) { returnHash.put(provider.toString() + "_" + person.getId(), person);}if (self != null) { returnHash.put(provider.toString() + "_" + self.getId(), self);}

Divide and Conquer getTopScoresForFriends()ArrayList<Hashtable<String,String>> returnList = null;OpenSocialClient c = osClient;

List<Object> args = new ArrayList<Object>();args.add("GetTopScoresForFriends");

while (friends.hasMoreElements()) { args.add(friends.nextElement());}try { returnList = getScoreInfoFromJson(callBackendRPC(args));} catch (Exception ex) { ex.printStackTrace();}return returnList;

Divide and Conquer getPicturesForFriends()

Hashtable<String,String> userPictures = new Hashtable....for (Hashtable<String,String> score : topScoreList) { String user = score.get(“user”); OpenSocialPerson person = friends.get(user); if (person.getField(“thumbnailUrl”) != null) { thumbnailUrl = person.getField(“thumbnailUrl”). getStringValue(); // ** download thumbnail here, save to file ** userPictures.put(user, user + “.img”); }}

Divide and Conquer when you die

Divide and Conquer postUpdate()

List<Object> args = new ArrayList<Object>();args.add("SetScore");args.add(provider.toString() + "_" + person.getId());args.add(level);args.add(timeTaken);args.add(person.getDisplayName());callBackendRPC(args);

Divide and Conquer social scoreboard

Summary

>OpenSocial supports innovative server-sideand mobile integrations via its support ofRESTful and RPC protocols

>The OpenSocial Java client libraries take allthe heavy lifting out of communicating viathese protocols.

>Any mobile, desktop or server-side Javadeveloper can easily integrate OpenSocialand social features into their applications!

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Chris SchalkRyan Boyd

Google Developer AdvocatesJavaOne 2009

Technology

JavaOne: Creating Serverside and Mobile Mashups with the OpenSocial Java client libraries