Since there's no signal indicating which version of the spec a signed request follows, I realized that this change will likely trip up existing app developers once Shindig changes to the new system.

Finding the appropriate bug in Shindig's issue tracker, I was happy to see that both parameters will be sent by both Java and PHP Shindig for the time being (at least until we move on to whichever version comes after 0.9). This should give a reasonable window for most developers to change their code.

If you're an app developer, it's important to change your signing code as more containers begin to support OpenSocial 0.9. It's a simple change - just check for the xoauth_public_key parameter, and if it's not available, then look for xoauth_signature_publickey instead. Once 0.9 has been fully deployed, you should be able to delete the fallback (although keeping it around for a while shouldn't break anything).

When working with OpenSocial gadgets, I usually find myself using Firebug to inspect an IFrame to get the URL of the gadget spec that is being loaded. While Firebug gives me access to this data, it's a little hard to get to, and I need to decode the URL before I can paste it into a browser. So to help with this, I created a Firebug extension which scans the current page to see if any OpenSocial gadgets have been loaded. If the extension finds any gadgets, it attempts to discover the XML spec URLs for all the gadgets on the page and lists these as links which will go directly to the gadget XML spec. (Note that this feature works for Shindig based websites, but will not work on MySpace).

Additionally, I wanted to be able to execute JavaScript code inside of the gadget IFrame (and not the container page, which Firebug lets you do normally). This kind of functionality really help debug gadgets, because you can test out JavaScript without needing to save and upload an XML file again (or even reload the page!). So I added a box below each XML spec URL which will let you execute any JavaScript you want, in the context of the gadget's IFrame.

You can find the extension on addons.mozilla.org here. Please leave a review on that site if you wind up using it!

To help make sense of it all, I've updated the OAuth Use Cases page on the OpenSocial wiki. You'll find additional diagrams and clearer request flows showing how data can be transferred between social networks, users, and third party application servers. Additionally, there are hypothetical examples showing where each type of OAuth comes in handy, as well as some links to container-specific resources for obtaining OAuth keys for your applications.

Previously, this string was:
Google OpenSocial agent (http://www.google.com/feedfetcher.html)

When the change goes live, the string will be:
Mozilla/5.0 (compatible) Feedfetcher-Google; (+http://www.google.com/feedfetcher.html)

This will be the agent used for all outgoing requests, including fetching gadget specs, osapi.http or gadgets.io.makeRequest calls, and proxied content fetches.

We're expecting few developers to be affected by this change, so if you're not checking the User-Agent for requests to your server, you shouldn't have to make any changes.

This guide should help answer a lot of the questions people first have when starting to develop OpenSocial applications with PHP. We've covered such topics as getting and installing the library, how to batch requests and deal with errors, and how to make simple OpenSocial requests for People, Activities, and App Data. Also included is our current roadmap so you can see what we're working on.

While every effort has been made to create a comprehensive developer's guide, we certainly understand that there still may be areas of the client library which are not fully documented or where the examples are unclear. If you see any place where the documentation can be improved, please take a minute to file a feature request in our issue tracker, and we'll be able to make the documentation better for everyone.

Happy Coding!
~Arne (on behalf of the PHP client library team)

Here they are translated into Chinese.  My goal is to get some of the new images and diagrams into the official documentation soon.

function sendNotification() {
  var params = {};
  params[opensocial.Message.Field.TITLE] =
      "Title of the notification goes here";
  params[opensocial.Message.Field.TYPE] =
      opensocial.Message.Type.PRIVATE_MESSAGE;
  var body="Text of the notification goes here";
  var message = opensocial.newMessage(body, params);
  var recipient = opensocial.DataRequest.PersonId.OWNER;
  opensocial.requestSendMessage(recipient, message,
      onSendNotification);
};

function onSendNotification(resp) {
  if (!resp.hadError() && resp.getData().status == "sent") {
    alert("The message was sent to the OWNER");
  } else {
    alert("There was a problem: " + resp.getErrorMessage());
  }
};

sendNotification();

function onPersonGot(result) {
  var response = result.get("person");
  if (response.hadError()) {
    output("There was a problem fetching this user: " + 
        response.getErrorCode());
  } else {
    output("Fetched " + 
        result.get("person").getData().getDisplayName());
  }
  gadgets.window.adjustHeight();
};

function closeGetPerson(id) {
  return function() {
    var params = {};
    var req = opensocial.newDataRequest();
    req.add(req.newFetchPersonRequest(id, params), "person");
    req.send(onPersonGot);
  };
};


function closePrintFriend(list) {
  return function(friend) {
    var item = document.createElement("li");
    var link = document.createElement("a");
    var text = document.createTextNode(friend.getDisplayName());
    list.appendChild(item);
    item.appendChild(link);
    item.appendChild(document.createTextNode(" [" + 
        friend.getId() + "]"));
    link.appendChild(text);
    link.onclick = closeGetPerson(friend.getId());
    link.href = "javascript:void(0);";
  };
};

function gotFriends(data) {
  var friends = data.get("of").getData();
  var list = document.createElement("ul");
  var main = document.getElementById("dom_handle")
  main.innerHTML = "";
  main.appendChild(list);
  friends.each(closePrintFriend(list));
  gadgets.window.adjustHeight();
};

function getFriends() {
  var params = {};
  params[opensocial.DataRequest.PeopleRequestFields.MAX] = 1000;
  var req = opensocial.newDataRequest();
  req.add(req.newFetchPeopleRequest(
      opensocial.DataRequest.Group.OWNER_FRIENDS, params), "of");
  req.send(gotFriends);
};

getFriends();

• opensocial.DataRequest.Person.OWNER
• opensocial.DataRequest.Person.VIEWER
• A string representing the OpenSocial ID of a person.

• opensocial.DataRequest.Group.OWNER_FRIENDS
• opensocial.DataRequest.Group.VIEWER_FRIENDS
• An array of strings, each representing the OpenSocial ID of a person.

• opensocial.IdSpec.PersonId.OWNER
• opensocial.IdSpec.PersonId.VIEWER
• A string representing the OpenSocial ID of a person.

• opensocial.DataRequest.newFetchPersonRequest
• opensocial.DataRequest.newUpdatePersonAppDataRequest
• opensocial.DataRequest.newRemovePersonAppDataRequest 
  

var params = {};
var req = opensocial.newDataRequest();
...
req.add(req.newFetchPeopleRequest(
    opensocial.DataRequest.Group.OWNER_FRIENDS, params);
req.send();

var params = {};
var idspec = opensocial.newIdSpec({ 
    "userId" : "OWNER", 
    "groupId" : "FRIENDS" 
});
...
req.add(req.newFetchPeopleRequest(
    idspec, params);
req.send();

var idspec = opensocial.newIdSpec({ 
    "userId" : "OWNER",  "groupId" : "SELF" 
});

var idspec = opensocial.newIdSpec({ 
    "userId" : "VIEWER",  "groupId" : "SELF" 
});

var idspec = opensocial.newIdSpec({ 
    "userId" : "OWNER",  "groupId" : "FRIENDS" 
});

var idspec = opensocial.newIdSpec({ 
    "userId" : "VIEWER",  "groupId" : "FRIENDS" 
});

• opensocial.DataRequest.newFetchActivitiesRequest
• opensocial.DataRequest.newFetchPeopleRequest
• opensocial.DataRequest.newFetchPersonAppDataRequest