Let's Code Test Driven JavaScript's Persona integration.

lctdjs-persona.js

// Copyright (c) 2012-2013 Titanium I.T. LLC. All rights reserved.
/*global window, document, navigator, XMLHttpRequest, alert, setupPersona, $*/

(function() {
    "use strict";

    var ready = false;

    window.setupPersona = function(email) {
        $(".tdjs-signin").click(onSignin);
        $(".tdjs-signout").click(onSignout);
        navigator.id.watch({
            loggedInUser: email,
            onlogin: postLoginRequest,
            onlogout: postLogoutRequest,
            onready: function () { ready = true; }
        });
    };

    function onSignin(event) {
        event.preventDefault();
        navigator.id.request({
            siteName: "Let’s Code JavaScript"
        });
    }

    function onSignout(event) {
        event.preventDefault();
        navigator.id.logout();
    }

    function postLoginRequest(assertion) {
        var post = $.post("/v3/auth/login", "assertion=" + assertion);
        post.done(function(data) {
            if (data === "ok") {
                window.location.reload();
            }
            else {
                alert("Login failed. Please try again.");
                // Must logout on failure or Persona will keep trying to validate assertion. But that will trigger
                // onlogout (postLogoutRequest()) synchronously, which will cause a window reload, so the logout must be
                // the last thing we do in this function.
                navigator.id.logout();
            }
        });
        post.fail(function(data, textStatus) {
            alert("Could not contact server to log in. Please try again.");
        });
    }

    function postLogoutRequest() {
        if (!ready) { return; }

        var post = $.post("/v3/auth/logout", "ios6_cache_buster=" + (new Date()).valueOf());
        post.done(function(data) {
            window.location.reload();
        });
        post.fail(function(data, textStatus) {
            alert("Could not contact server to log out. Please try again.");
        });
    }

}());