dojo.provide("dojo.io.ScriptSrcIO");
dojo.require("dojo.io.BrowserIO");
dojo.require("dojo.undo.browser");
//FIXME: should constantParams be JS object?
//FIXME: check dojo.io calls. Can we move the BrowserIO defined calls somewhere
// else so that we don't depend on BrowserIO at all? The dependent calls
// have to do with dealing with forms and making query params from JS object.
/**
* See test_ScriptSrcIO.html for usage information.
* Notes:
* - The watchInFlight timer is set to 100 ms instead of 10ms (which is what BrowserIO.js uses).
*/
dojo.io.ScriptSrcTransport = new function(){
this.preventCache = false; // if this is true, we'll always force GET requests to not cache
this.maxUrlLength = 1000; //Used to calculate if script request should be multipart.
this.inFlightTimer = null;
this.DsrStatusCodes = {
Continue: 100,
Ok: 200,
Error: 500
};
this.startWatchingInFlight = function(){
//summary: Internal method to start the process of watching for in-flight requests.
if(!this.inFlightTimer){
this.inFlightTimer = setInterval("dojo.io.ScriptSrcTransport.watchInFlight();", 100);
}
}
this.watchInFlight = function(){
//summary: Internal method to watch for in-flight requests.
var totalCount = 0;
var doneCount = 0;
for(var param in this._state){
totalCount++;
var currentState = this._state[param];
if(currentState.isDone){
doneCount++;
delete this._state[param];
}else if(!currentState.isFinishing){
var listener = currentState.kwArgs;
try{
if(currentState.checkString && eval("typeof(" + currentState.checkString + ") != 'undefined'")){
currentState.isFinishing = true;
this._finish(currentState, "load");
doneCount++;
delete this._state[param];
}else if(listener.timeoutSeconds && listener.timeout){
if(currentState.startTime + (listener.timeoutSeconds * 1000) < (new Date()).getTime()){
currentState.isFinishing = true;
this._finish(currentState, "timeout");
doneCount++;
delete this._state[param];
}
}else if(!listener.timeoutSeconds){
//Increment the done count if no timeout is specified, so
//that we turn off the timer if all that is left in the state
//list are things we can't clean up because they fail without
//getting a callback.
doneCount++;
}
}catch(e){
currentState.isFinishing = true;
this._finish(currentState, "error", {status: this.DsrStatusCodes.Error, response: e});
}
}
}
if(doneCount >= totalCount){
clearInterval(this.inFlightTimer);
this.inFlightTimer = null;
}
}
this.canHandle = function(/*dojo.io.Request*/kwArgs){
//summary: Tells dojo.io.bind() if this is a good transport to
//use for the particular type of request. This type of transport can only
//handle responses that are JavaScript or JSON that is passed to a JavaScript
//callback. It can only do asynchronous binds, is limited to GET HTTP method
//requests, and cannot handle formNodes. However, it has the advantage of being
//able to do cross-domain requests.
return dojo.lang.inArray(["text/javascript", "text/json", "application/json"], (kwArgs["mimetype"].toLowerCase()))
&& (kwArgs["method"].toLowerCase() == "get")
&& !(kwArgs["formNode"] && dojo.io.formHasFile(kwArgs["formNode"]))
&& (!kwArgs["sync"] || kwArgs["sync"] == false)
&& !kwArgs["file"]
&& !kwArgs["multipart"];
}
this.removeScripts = function(){
//summary: Removes any script tags from the DOM that may have been added by ScriptSrcTransport.
//description: Be careful though, by removing them from the script, you may invalidate some
//script objects that were defined by the js file that was pulled in as the
//src of the script tag. Test carefully if you decide to call this method.
//In MSIE 6 (and probably 5.x), if you remove the script element while
//part of the response script is still executing, the browser might crash.
var scripts = document.getElementsByTagName("script");
for(var i = 0; scripts && i < scripts.length; i++){
var scriptTag = scripts[i];
if(scriptTag.className == "ScriptSrcTransport"){
var parent = scriptTag.parentNode;
parent.removeChild(scriptTag);
i--; //Set the index back one since we removed an item.
}
}
}
this.bind = function(/*dojo.io.Request*/kwArgs){
//summary: function that sends the request to the server.
//description: See the Dojo Book page on this transport for a full
//description of supported kwArgs properties and usage:
//http://manual.dojotoolkit.org/WikiHome/DojoDotBook/Book25
//START duplication from BrowserIO.js (some changes made)
var url = kwArgs.url;
var query = "";
if(kwArgs["formNode"]){
var ta = kwArgs.formNode.getAttribute("action");
if((ta)&&(!kwArgs["url"])){ url = ta; }
var tp = kwArgs.formNode.getAttribute("method");
if((tp)&&(!kwArgs["method"])){ kwArgs.method = tp; }
query += dojo.io.encodeForm(kwArgs.formNode, kwArgs.encoding, kwArgs["formFilter"]);
}
if(url.indexOf("#") > -1) {
dojo.debug("Warning: dojo.io.bind: stripping hash values from url:", url);
url = url.split("#")[0];
}
//Break off the domain/path of the URL.
var urlParts = url.split("?");
if(urlParts && urlParts.length == 2){
url = urlParts[0];
query += (query ? "&" : "") + urlParts[1];
}
if(kwArgs["backButton"] || kwArgs["back"] || kwArgs["changeUrl"]){
dojo.undo.browser.addToHistory(kwArgs);
}
//Create an ID for the request.
var id = kwArgs["apiId"] ? kwArgs["apiId"] : "id" + this._counter++;
//Fill out any other content pieces.
var content = kwArgs["content"];
var jsonpName = kwArgs.jsonParamName;
if(kwArgs.sendTransport || jsonpName) {
if (!content){
content = {};
}
if(kwArgs.sendTransport){
content["dojo.transport"] = "scriptsrc";
}
if(jsonpName){
content[jsonpName] = "dojo.io.ScriptSrcTransport._state." + id + ".jsonpCall";
}
}
if(kwArgs.postContent){
query = kwArgs.postContent;
}else if(content){
query += ((query) ? "&" : "") + dojo.io.argsFromMap(content, kwArgs.encoding, jsonpName);
}
//END duplication from BrowserIO.js
//START DSR
//If an apiId is specified, then we want to make sure useRequestId is true.
if(kwArgs["apiId"]){
kwArgs["useRequestId"] = true;
}
//Set up the state for this request.
var state = {
"id": id,
"idParam": "_dsrid=" + id,
"url": url,
"query": query,
"kwArgs": kwArgs,
"startTime": (new Date()).getTime(),
"isFinishing": false
};
if(!url){
//Error. An URL is needed.
this._finish(state, "error", {status: this.DsrStatusCodes.Error, statusText: "url.none"});
return;
}
//If this is a jsonp request, intercept the jsonp callback
if(content && content[jsonpName]){
state.jsonp = content[jsonpName];
state.jsonpCall = function(data){
if(data["Error"]||data["error"]){
if(dojo["json"] && dojo["json"]["serialize"]){
dojo.debug(dojo.json.serialize(data));
}
dojo.io.ScriptSrcTransport._finish(this, "error", data);
}else{
dojo.io.ScriptSrcTransport._finish(this, "load", data);
}
};
}
//Only store the request state on the state tracking object if a callback
//is expected or if polling on a checkString will be done.
if(kwArgs["useRequestId"] || kwArgs["checkString"] || state["jsonp"]){
this._state[id] = state;
}
//A checkstring is a string that if evaled will not be undefined once the
//script src loads. Used as an alternative to depending on a callback from
//the script file. If this is set, then multipart is not assumed to be used,
//since multipart requires a specific callback. With checkString we will be doing
//polling.
if(kwArgs["checkString"]){
state.checkString = kwArgs["checkString"];
}
//Constant params are parameters that should always be sent with each
//part of a multipart URL.
state.constantParams = (kwArgs["constantParams"] == null ? "" : kwArgs["constantParams"]);
if(kwArgs["preventCache"] ||
(this.preventCache == true && kwArgs["preventCache"] != false)){
state.nocacheParam = "dojo.preventCache=" + new Date().valueOf();
}else{
state.nocacheParam = "";
}
//Get total length URL, if we were to do it as one URL.
//Add some padding, extra & separators.
var urlLength = state.url.length + state.query.length + state.constantParams.length
+ state.nocacheParam.length + this._extraPaddingLength;
if(kwArgs["useRequestId"]){
urlLength += state.idParam.length;
}
if(!kwArgs["checkString"] && kwArgs["useRequestId"]
&& !state["jsonp"] && !kwArgs["forceSingleRequest"]
&& urlLength > this.maxUrlLength){
if(url > this.maxUrlLength){
//Error. The URL domain and path are too long. We can't
//segment that, so return an error.
this._finish(state, "error", {status: this.DsrStatusCodes.Error, statusText: "url.tooBig"});
return;
}else{
//Start the multiple requests.
this._multiAttach(state, 1);
}
}else{
//Send one URL.
var queryParams = [state.constantParams, state.nocacheParam, state.query];
if(kwArgs["useRequestId"] && !state["jsonp"]){
queryParams.unshift(state.idParam);
}
var finalUrl = this._buildUrl(state.url, queryParams);
//Track the final URL in case we need to use that instead of api ID when receiving
//the load callback.
state.finalUrl = finalUrl;
this._attach(state.id, finalUrl);
}
//END DSR
this.startWatchingInFlight();
}
//Private properties/methods
this._counter = 1;
this._state = {};
this._extraPaddingLength = 16;
//Is there a dojo function for this already?
this._buildUrl = function(url, nameValueArray){
var finalUrl = url;
var joiner = "?";
for(var i = 0; i < nameValueArray.length; i++){
if(nameValueArray[i]){
finalUrl += joiner + nameValueArray[i];
joiner = "&";
}
}
return finalUrl;
}
this._attach = function(id, url){
//Attach the script to the DOM.
var element = document.createElement("script");
element.type = "text/javascript";
element.src = url;
element.id = id;
element.className = "ScriptSrcTransport";
document.getElementsByTagName("head")[0].appendChild(element);
}
this._multiAttach = function(state, part){
//Check to make sure we still have a query to send up. This is mostly
//a protection from a goof on the server side when it sends a part OK
//response instead of a final response.
if(state.query == null){
this._finish(state, "error", {status: this.DsrStatusCodes.Error, statusText: "query.null"});
return;
}
if(!state.constantParams){
state.constantParams = "";
}
//How much of the query can we take?
//Add a padding constant to account for _part and a couple extra amperstands.
//Also add space for id since we'll need it now.
var queryMax = this.maxUrlLength - state.idParam.length
- state.constantParams.length - state.url.length
- state.nocacheParam.length - this._extraPaddingLength;
//Figure out if this is the last part.
var isDone = state.query.length < queryMax;
//Break up the query string if necessary.
var currentQuery;
if(isDone){
currentQuery = state.query;
state.query = null;
}else{
//Find the & or = nearest the max url length.
var ampEnd = state.query.lastIndexOf("&", queryMax - 1);
var eqEnd = state.query.lastIndexOf("=", queryMax - 1);
//See if & is closer, or if = is right at the edge,
//which means we should put it on the next URL.
if(ampEnd > eqEnd || eqEnd == queryMax - 1){
//& is nearer the end. So just chop off from there.
currentQuery = state.query.substring(0, ampEnd);
state.query = state.query.substring(ampEnd + 1, state.query.length) //strip off amperstand with the + 1.
}else{
//= is nearer the end. Take the max amount possible.
currentQuery = state.query.substring(0, queryMax);
//Find the last query name in the currentQuery so we can prepend it to
//ampEnd. Could be -1 (not there), so account for that.
var queryName = currentQuery.substring((ampEnd == -1 ? 0 : ampEnd + 1), eqEnd);
state.query = queryName + "=" + state.query.substring(queryMax, state.query.length);
}
}
//Now send a part of the script
var queryParams = [currentQuery, state.idParam, state.constantParams, state.nocacheParam];
if(!isDone){
queryParams.push("_part=" + part);
}
var url = this._buildUrl(state.url, queryParams);
this._attach(state.id + "_" + part, url);
}
this._finish = function(state, callback, event){
if(callback != "partOk" && !state.kwArgs[callback] && !state.kwArgs["handle"]){
//Ignore "partOk" because that is an internal callback.
if(callback == "error"){
state.isDone = true;
throw event;
}
}else{
switch(callback){
case "load":
var response = event ? event.response : null;
if(!response){
response = event;
}
state.kwArgs[(typeof state.kwArgs.load == "function") ? "load" : "handle"]("load", response, event, state.kwArgs);
state.isDone = true;
break;
case "partOk":
var part = parseInt(event.response.part, 10) + 1;
//Update the constant params, if any.
if(event.response.constantParams){
state.constantParams = event.response.constantParams;
}
this._multiAttach(state, part);
state.isDone = false;
break;
case "error":
state.kwArgs[(typeof state.kwArgs.error == "function") ? "error" : "handle"]("error", event.response, event, state.kwArgs);
state.isDone = true;
break;
default:
state.kwArgs[(typeof state.kwArgs[callback] == "function") ? callback : "handle"](callback, event, event, state.kwArgs);
state.isDone = true;
}
}
}
dojo.io.transports.addTransport("ScriptSrcTransport");
}
//Define callback handler.
window.onscriptload = function(event){
var state = null;
var transport = dojo.io.ScriptSrcTransport;
//Find the matching state object for event ID.
if(transport._state[event.id]){
state = transport._state[event.id];
}else{
//The ID did not match directly to an entry in the state list.
//Try searching the state objects for a matching original URL.
var tempState;
for(var param in transport._state){
tempState = transport._state[param];
if(tempState.finalUrl && tempState.finalUrl == event.id){
state = tempState;
break;
}
}
//If no matching original URL is found, then use the URL that was actually used
//in the SCRIPT SRC attribute.
if(state == null){
var scripts = document.getElementsByTagName("script");
for(var i = 0; scripts && i < scripts.length; i++){
var scriptTag = scripts[i];
if(scriptTag.getAttribute("class") == "ScriptSrcTransport"
&& scriptTag.src == event.id){
state = transport._state[scriptTag.id];
break;
}
}
}
//If state is still null, then throw an error.
if(state == null){
throw "No matching state for onscriptload event.id: " + event.id;
}
}
var callbackName = "error";
switch(event.status){
case dojo.io.ScriptSrcTransport.DsrStatusCodes.Continue:
//A part of a multipart request.
callbackName = "partOk";
break;
case dojo.io.ScriptSrcTransport.DsrStatusCodes.Ok:
//Successful reponse.
callbackName = "load";
break;
}
transport._finish(state, callbackName, event);
};