Commit 0ab5cb9e authored by Romain Courteaud's avatar Romain Courteaud

Release version 0.8.0

parent 11ed2094
/*
* js_channel is a very lightweight abstraction on top of
* postMessage which defines message formats and semantics
* to support interactions more rich than just message passing
* js_channel supports:
* + query/response - traditional rpc
* + query/update/response - incremental async return of results
* to a query
* + notifications - fire and forget
* + error handling
*
* js_channel is based heavily on json-rpc, but is focused at the
* problem of inter-iframe RPC.
*
* Message types:
* There are 5 types of messages that can flow over this channel,
* and you may determine what type of message an object is by
* examining its parameters:
* 1. Requests
* + integer id
* + string method
* + (optional) any params
* 2. Callback Invocations (or just "Callbacks")
* + integer id
* + string callback
* + (optional) params
* 3. Error Responses (or just "Errors)
* + integer id
* + string error
* + (optional) string message
* 4. Responses
* + integer id
* + (optional) any result
* 5. Notifications
* + string method
* + (optional) any params
*/
;var Channel = (function() {
"use strict";
// current transaction id, start out at a random *odd* number between 1 and a million
// There is one current transaction counter id per page, and it's shared between
// channel instances. That means of all messages posted from a single javascript
// evaluation context, we'll never have two with the same id.
var s_curTranId = Math.floor(Math.random()*1000001);
// no two bound channels in the same javascript evaluation context may have the same origin, scope, and window.
// futher if two bound channels have the same window and scope, they may not have *overlapping* origins
// (either one or both support '*'). This restriction allows a single onMessage handler to efficiently
// route messages based on origin and scope. The s_boundChans maps origins to scopes, to message
// handlers. Request and Notification messages are routed using this table.
// Finally, channels are inserted into this table when built, and removed when destroyed.
var s_boundChans = { };
// add a channel to s_boundChans, throwing if a dup exists
function s_addBoundChan(win, origin, scope, handler) {
function hasWin(arr) {
for (var i = 0; i < arr.length; i++) if (arr[i].win === win) return true;
return false;
}
// does she exist?
var exists = false;
if (origin === '*') {
// we must check all other origins, sadly.
for (var k in s_boundChans) {
if (!s_boundChans.hasOwnProperty(k)) continue;
if (k === '*') continue;
if (typeof s_boundChans[k][scope] === 'object') {
exists = hasWin(s_boundChans[k][scope]);
if (exists) break;
}
}
} else {
// we must check only '*'
if ((s_boundChans['*'] && s_boundChans['*'][scope])) {
exists = hasWin(s_boundChans['*'][scope]);
}
if (!exists && s_boundChans[origin] && s_boundChans[origin][scope])
{
exists = hasWin(s_boundChans[origin][scope]);
}
}
if (exists) throw "A channel is already bound to the same window which overlaps with origin '"+ origin +"' and has scope '"+scope+"'";
if (typeof s_boundChans[origin] != 'object') s_boundChans[origin] = { };
if (typeof s_boundChans[origin][scope] != 'object') s_boundChans[origin][scope] = [ ];
s_boundChans[origin][scope].push({win: win, handler: handler});
}
function s_removeBoundChan(win, origin, scope) {
var arr = s_boundChans[origin][scope];
for (var i = 0; i < arr.length; i++) {
if (arr[i].win === win) {
arr.splice(i,1);
}
}
if (s_boundChans[origin][scope].length === 0) {
delete s_boundChans[origin][scope];
}
}
function s_isArray(obj) {
if (Array.isArray) return Array.isArray(obj);
else {
return (obj.constructor.toString().indexOf("Array") != -1);
}
}
// No two outstanding outbound messages may have the same id, period. Given that, a single table
// mapping "transaction ids" to message handlers, allows efficient routing of Callback, Error, and
// Response messages. Entries are added to this table when requests are sent, and removed when
// responses are received.
var s_transIds = { };
// class singleton onMessage handler
// this function is registered once and all incoming messages route through here. This
// arrangement allows certain efficiencies, message data is only parsed once and dispatch
// is more efficient, especially for large numbers of simultaneous channels.
var s_onMessage = function(e) {
try {
var m = JSON.parse(e.data);
if (typeof m !== 'object' || m === null) throw "malformed";
} catch(e) {
// just ignore any posted messages that do not consist of valid JSON
return;
}
var w = e.source;
var o = e.origin;
var s, i, meth;
if (typeof m.method === 'string') {
var ar = m.method.split('::');
if (ar.length == 2) {
s = ar[0];
meth = ar[1];
} else {
meth = m.method;
}
}
if (typeof m.id !== 'undefined') i = m.id;
// w is message source window
// o is message origin
// m is parsed message
// s is message scope
// i is message id (or undefined)
// meth is unscoped method name
// ^^ based on these factors we can route the message
// if it has a method it's either a notification or a request,
// route using s_boundChans
if (typeof meth === 'string') {
var delivered = false;
if (s_boundChans[o] && s_boundChans[o][s]) {
for (var j = 0; j < s_boundChans[o][s].length; j++) {
if (s_boundChans[o][s][j].win === w) {
s_boundChans[o][s][j].handler(o, meth, m);
delivered = true;
break;
}
}
}
if (!delivered && s_boundChans['*'] && s_boundChans['*'][s]) {
for (var j = 0; j < s_boundChans['*'][s].length; j++) {
if (s_boundChans['*'][s][j].win === w) {
s_boundChans['*'][s][j].handler(o, meth, m);
break;
}
}
}
}
// otherwise it must have an id (or be poorly formed
else if (typeof i != 'undefined') {
if (s_transIds[i]) s_transIds[i](o, meth, m);
}
};
// Setup postMessage event listeners
if (window.addEventListener) window.addEventListener('message', s_onMessage, false);
else if(window.attachEvent) window.attachEvent('onmessage', s_onMessage);
/* a messaging channel is constructed from a window and an origin.
* the channel will assert that all messages received over the
* channel match the origin
*
* Arguments to Channel.build(cfg):
*
* cfg.window - the remote window with which we'll communicate
* cfg.origin - the expected origin of the remote window, may be '*'
* which matches any origin
* cfg.scope - the 'scope' of messages. a scope string that is
* prepended to message names. local and remote endpoints
* of a single channel must agree upon scope. Scope may
* not contain double colons ('::').
* cfg.debugOutput - A boolean value. If true and window.console.log is
* a function, then debug strings will be emitted to that
* function.
* cfg.debugOutput - A boolean value. If true and window.console.log is
* a function, then debug strings will be emitted to that
* function.
* cfg.postMessageObserver - A function that will be passed two arguments,
* an origin and a message. It will be passed these immediately
* before messages are posted.
* cfg.gotMessageObserver - A function that will be passed two arguments,
* an origin and a message. It will be passed these arguments
* immediately after they pass scope and origin checks, but before
* they are processed.
* cfg.onReady - A function that will be invoked when a channel becomes "ready",
* this occurs once both sides of the channel have been
* instantiated and an application level handshake is exchanged.
* the onReady function will be passed a single argument which is
* the channel object that was returned from build().
*/
return {
build: function(cfg) {
var debug = function(m) {
if (cfg.debugOutput && window.console && window.console.log) {
// try to stringify, if it doesn't work we'll let javascript's built in toString do its magic
try { if (typeof m !== 'string') m = JSON.stringify(m); } catch(e) { }
console.log("["+chanId+"] " + m);
}
};
/* browser capabilities check */
if (!window.postMessage) throw("jschannel cannot run this browser, no postMessage");
if (!window.JSON || !window.JSON.stringify || ! window.JSON.parse) {
throw("jschannel cannot run this browser, no JSON parsing/serialization");
}
/* basic argument validation */
if (typeof cfg != 'object') throw("Channel build invoked without a proper object argument");
if (!cfg.window || !cfg.window.postMessage) throw("Channel.build() called without a valid window argument");
/* we'd have to do a little more work to be able to run multiple channels that intercommunicate the same
* window... Not sure if we care to support that */
if (window === cfg.window) throw("target window is same as present window -- not allowed");
// let's require that the client specify an origin. if we just assume '*' we'll be
// propagating unsafe practices. that would be lame.
var validOrigin = false;
if (typeof cfg.origin === 'string') {
var oMatch;
if (cfg.origin === "*") validOrigin = true;
// allow valid domains under http and https. Also, trim paths off otherwise valid origins.
else if (null !== (oMatch = cfg.origin.match(/^https?:\/\/(?:[-a-zA-Z0-9_\.])+(?::\d+)?/))) {
cfg.origin = oMatch[0].toLowerCase();
validOrigin = true;
}
}
if (!validOrigin) throw ("Channel.build() called with an invalid origin");
if (typeof cfg.scope !== 'undefined') {
if (typeof cfg.scope !== 'string') throw 'scope, when specified, must be a string';
if (cfg.scope.split('::').length > 1) throw "scope may not contain double colons: '::'";
}
/* private variables */
// generate a random and psuedo unique id for this channel
var chanId = (function () {
var text = "";
var alpha = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
for(var i=0; i < 5; i++) text += alpha.charAt(Math.floor(Math.random() * alpha.length));
return text;
})();
// registrations: mapping method names to call objects
var regTbl = { };
// current oustanding sent requests
var outTbl = { };
// current oustanding received requests
var inTbl = { };
// are we ready yet? when false we will block outbound messages.
var ready = false;
var pendingQueue = [ ];
var createTransaction = function(id,origin,callbacks) {
var shouldDelayReturn = false;
var completed = false;
return {
origin: origin,
invoke: function(cbName, v) {
// verify in table
if (!inTbl[id]) throw "attempting to invoke a callback of a nonexistent transaction: " + id;
// verify that the callback name is valid
var valid = false;
for (var i = 0; i < callbacks.length; i++) if (cbName === callbacks[i]) { valid = true; break; }
if (!valid) throw "request supports no such callback '" + cbName + "'";
// send callback invocation
postMessage({ id: id, callback: cbName, params: v});
},
error: function(error, message) {
completed = true;
// verify in table
if (!inTbl[id]) throw "error called for nonexistent message: " + id;
// remove transaction from table
delete inTbl[id];
// send error
postMessage({ id: id, error: error, message: message });
},
complete: function(v) {
completed = true;
// verify in table
if (!inTbl[id]) throw "complete called for nonexistent message: " + id;
// remove transaction from table
delete inTbl[id];
// send complete
postMessage({ id: id, result: v });
},
delayReturn: function(delay) {
if (typeof delay === 'boolean') {
shouldDelayReturn = (delay === true);
}
return shouldDelayReturn;
},
completed: function() {
return completed;
}
};
};
var setTransactionTimeout = function(transId, timeout, method) {
return window.setTimeout(function() {
if (outTbl[transId]) {
// XXX: what if client code raises an exception here?
var msg = "timeout (" + timeout + "ms) exceeded on method '" + method + "'";
(1,outTbl[transId].error)("timeout_error", msg);
delete outTbl[transId];
delete s_transIds[transId];
}
}, timeout);
};
var onMessage = function(origin, method, m) {
// if an observer was specified at allocation time, invoke it
if (typeof cfg.gotMessageObserver === 'function') {
// pass observer a clone of the object so that our
// manipulations are not visible (i.e. method unscoping).
// This is not particularly efficient, but then we expect
// that message observers are primarily for debugging anyway.
try {
cfg.gotMessageObserver(origin, m);
} catch (e) {
debug("gotMessageObserver() raised an exception: " + e.toString());
}
}
// now, what type of message is this?
if (m.id && method) {
// a request! do we have a registered handler for this request?
if (regTbl[method]) {
var trans = createTransaction(m.id, origin, m.callbacks ? m.callbacks : [ ]);
inTbl[m.id] = { };
try {
// callback handling. we'll magically create functions inside the parameter list for each
// callback
if (m.callbacks && s_isArray(m.callbacks) && m.callbacks.length > 0) {
for (var i = 0; i < m.callbacks.length; i++) {
var path = m.callbacks[i];
var obj = m.params;
var pathItems = path.split('/');
for (var j = 0; j < pathItems.length - 1; j++) {
var cp = pathItems[j];
if (typeof obj[cp] !== 'object') obj[cp] = { };
obj = obj[cp];
}
obj[pathItems[pathItems.length - 1]] = (function() {
var cbName = path;
return function(params) {
return trans.invoke(cbName, params);
};
})();
}
}
var resp = regTbl[method](trans, m.params);
if (!trans.delayReturn() && !trans.completed()) trans.complete(resp);
} catch(e) {
// automagic handling of exceptions:
var error = "runtime_error";
var message = null;
// * if it's a string then it gets an error code of 'runtime_error' and string is the message
if (typeof e === 'string') {
message = e;
} else if (typeof e === 'object') {
// either an array or an object
// * if it's an array of length two, then array[0] is the code, array[1] is the error message
if (e && s_isArray(e) && e.length == 2) {
error = e[0];
message = e[1];
}
// * if it's an object then we'll look form error and message parameters
else if (typeof e.error === 'string') {
error = e.error;
if (!e.message) message = "";
else if (typeof e.message === 'string') message = e.message;
else e = e.message; // let the stringify/toString message give us a reasonable verbose error string
}
}
// message is *still* null, let's try harder
if (message === null) {
try {
message = JSON.stringify(e);
/* On MSIE8, this can result in 'out of memory', which
* leaves message undefined. */
if (typeof(message) == 'undefined')
message = e.toString();
} catch (e2) {
message = e.toString();
}
}
trans.error(error,message);
}
}
} else if (m.id && m.callback) {
if (!outTbl[m.id] ||!outTbl[m.id].callbacks || !outTbl[m.id].callbacks[m.callback])
{
debug("ignoring invalid callback, id:"+m.id+ " (" + m.callback +")");
} else {
// XXX: what if client code raises an exception here?
outTbl[m.id].callbacks[m.callback](m.params);
}
} else if (m.id) {
if (!outTbl[m.id]) {
debug("ignoring invalid response: " + m.id);
} else {
// XXX: what if client code raises an exception here?
if (m.error) {
(1,outTbl[m.id].error)(m.error, m.message);
} else {
if (m.result !== undefined) (1,outTbl[m.id].success)(m.result);
else (1,outTbl[m.id].success)();
}
delete outTbl[m.id];
delete s_transIds[m.id];
}
} else if (method) {
// tis a notification.
if (regTbl[method]) {
// yep, there's a handler for that.
// transaction has only origin for notifications.
regTbl[method]({ origin: origin }, m.params);
// if the client throws, we'll just let it bubble out
// what can we do? Also, here we'll ignore return values
}
}
};
// now register our bound channel for msg routing
s_addBoundChan(cfg.window, cfg.origin, ((typeof cfg.scope === 'string') ? cfg.scope : ''), onMessage);
// scope method names based on cfg.scope specified when the Channel was instantiated
var scopeMethod = function(m) {
if (typeof cfg.scope === 'string' && cfg.scope.length) m = [cfg.scope, m].join("::");
return m;
};
// a small wrapper around postmessage whose primary function is to handle the
// case that clients start sending messages before the other end is "ready"
var postMessage = function(msg, force) {
if (!msg) throw "postMessage called with null message";
// delay posting if we're not ready yet.
var verb = (ready ? "post " : "queue ");
debug(verb + " message: " + JSON.stringify(msg));
if (!force && !ready) {
pendingQueue.push(msg);
} else {
if (typeof cfg.postMessageObserver === 'function') {
try {
cfg.postMessageObserver(cfg.origin, msg);
} catch (e) {
debug("postMessageObserver() raised an exception: " + e.toString());
}
}
cfg.window.postMessage(JSON.stringify(msg), cfg.origin);
}
};
var onReady = function(trans, type) {
debug('ready msg received');
if (ready) throw "received ready message while in ready state. help!";
if (type === 'ping') {
chanId += '-R';
} else {
chanId += '-L';
}
obj.unbind('__ready'); // now this handler isn't needed any more.
ready = true;
debug('ready msg accepted.');
if (type === 'ping') {
obj.notify({ method: '__ready', params: 'pong' });
}
// flush queue
while (pendingQueue.length) {
postMessage(pendingQueue.pop());
}
// invoke onReady observer if provided
if (typeof cfg.onReady === 'function') cfg.onReady(obj);
};
var obj = {
// tries to unbind a bound message handler. returns false if not possible
unbind: function (method) {
if (regTbl[method]) {
if (!(delete regTbl[method])) throw ("can't delete method: " + method);
return true;
}
return false;
},
bind: function (method, cb) {
if (!method || typeof method !== 'string') throw "'method' argument to bind must be string";
if (!cb || typeof cb !== 'function') throw "callback missing from bind params";
if (regTbl[method]) throw "method '"+method+"' is already bound!";
regTbl[method] = cb;
return this;
},
call: function(m) {
if (!m) throw 'missing arguments to call function';
if (!m.method || typeof m.method !== 'string') throw "'method' argument to call must be string";
if (!m.success || typeof m.success !== 'function') throw "'success' callback missing from call";
// now it's time to support the 'callback' feature of jschannel. We'll traverse the argument
// object and pick out all of the functions that were passed as arguments.
var callbacks = { };
var callbackNames = [ ];
var pruneFunctions = function (path, obj) {
if (typeof obj === 'object') {
for (var k in obj) {
if (!obj.hasOwnProperty(k)) continue;
var np = path + (path.length ? '/' : '') + k;
if (typeof obj[k] === 'function') {
callbacks[np] = obj[k];
callbackNames.push(np);
delete obj[k];
} else if (typeof obj[k] === 'object') {
pruneFunctions(np, obj[k]);
}
}
}
};
pruneFunctions("", m.params);
// build a 'request' message and send it
var msg = { id: s_curTranId, method: scopeMethod(m.method), params: m.params };
if (callbackNames.length) msg.callbacks = callbackNames;
if (m.timeout)
// XXX: This function returns a timeout ID, but we don't do anything with it.
// We might want to keep track of it so we can cancel it using clearTimeout()
// when the transaction completes.
setTransactionTimeout(s_curTranId, m.timeout, scopeMethod(m.method));
// insert into the transaction table
outTbl[s_curTranId] = { callbacks: callbacks, error: m.error, success: m.success };
s_transIds[s_curTranId] = onMessage;
// increment current id
s_curTranId++;
postMessage(msg);
},
notify: function(m) {
if (!m) throw 'missing arguments to notify function';
if (!m.method || typeof m.method !== 'string') throw "'method' argument to notify must be string";
// no need to go into any transaction table
postMessage({ method: scopeMethod(m.method), params: m.params });
},
destroy: function () {
s_removeBoundChan(cfg.window, cfg.origin, ((typeof cfg.scope === 'string') ? cfg.scope : ''));
if (window.removeEventListener) window.removeEventListener('message', onMessage, false);
else if(window.detachEvent) window.detachEvent('onmessage', onMessage);
ready = false;
regTbl = { };
inTbl = { };
outTbl = { };
cfg.origin = null;
pendingQueue = [ ];
debug("channel destroyed");
chanId = "";
}
};
obj.bind('__ready', onReady);
setTimeout(function() {
postMessage({ method: scopeMethod('__ready'), params: "ping" }, true);
}, 0);
return obj;
}
};
})();
;/*
* DOMParser HTML extension
* 2012-09-04
*
* By Eli Grey, http://eligrey.com
* Public domain.
* NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
*/
/*! @source https://gist.github.com/1129031 */
(function (DOMParser) {
"use strict";
var DOMParser_proto = DOMParser.prototype,
real_parseFromString = DOMParser_proto.parseFromString;
// Firefox/Opera/IE throw errors on unsupported types
try {
// WebKit returns null on unsupported types
if ((new DOMParser()).parseFromString("", "text/html")) {
// text/html parsing is natively supported
return;
}
} catch (ignore) {}
DOMParser_proto.parseFromString = function (markup, type) {
var result, doc, doc_elt, first_elt;
if (/^\s*text\/html\s*(?:;|$)/i.test(type)) {
doc = document.implementation.createHTMLDocument("");
doc_elt = doc.documentElement;
doc_elt.innerHTML = markup;
first_elt = doc_elt.firstElementChild;
if (doc_elt.childElementCount === 1
&& first_elt.localName.toLowerCase() === "html") {
doc.replaceChild(first_elt, doc_elt);
}
result = doc;
} else {
result = real_parseFromString.apply(this, arguments);
}
return result;
};
}(DOMParser));
;// IE does not support have Document.prototype.contains.
if (typeof document.contains !== 'function') {
Document.prototype.contains = function(node) {
if (node === this || node.parentNode === this)
return true;
return this.documentElement.contains(node);
}
}
;/*! RenderJs */
/*jslint nomen: true*/
/*
* renderJs - Generic Gadget library renderer.
* http://www.renderjs.org/documentation
*/
(function (document, window, RSVP, DOMParser, Channel, MutationObserver,
Node, FileReader, Blob) {
"use strict";
function readBlobAsDataURL(blob) {
var fr = new FileReader();
return new RSVP.Promise(function (resolve, reject) {
fr.addEventListener("load", function (evt) {
resolve(evt.target.result);
});
fr.addEventListener("error", reject);
fr.readAsDataURL(blob);
}, function () {
fr.abort();
});
}
function ajax(url) {
var xhr;
function resolver(resolve, reject) {
function handler() {
try {
if (xhr.readyState === 0) {
// UNSENT
reject(xhr);
} else if (xhr.readyState === 4) {
// DONE
if ((xhr.status < 200) || (xhr.status >= 300) ||
(!/^text\/html[;]?/.test(
xhr.getResponseHeader("Content-Type") || ""
))) {
reject(xhr);
} else {
resolve(xhr);
}
}
} catch (e) {
reject(e);
}
}
xhr = new XMLHttpRequest();
xhr.open("GET", url);
xhr.onreadystatechange = handler;
xhr.setRequestHeader('Accept', 'text/html');