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Detecting when ajax success function takes longer than 5 seconds and redirect

Hello I have this script that moves from one page through a href without page load.
It works perfectly, but I want to redirect to the requested page if Ajax takes longer than 5 seconds to respond, usually caused by probably slow internet connection.
In this case: Stop the script and load the page normally.
Firstly the href:
new
New 1
This is the script:
<script>
$(function(){
$("a[rel='tab']").click(function(e){
pageurl = $(this).attr('href'); //get the href clicked
$.ajax({url:pageurl+'?rel=tab',
success: function(data){
$('#mole').html(data);
}
});
if(pageurl!=window.location){
window.history.pushState({
path:pageurl
},'',pageurl);
}
return false;
});
});
$(window).bind('popstate', function(){
$.ajax({
url:location.pathname+'?rel=tab',
success: function(data){
// here how do I detect if the success takes longer than 5 seconds
// stop the script and load the page normally which is the URL parameter in ajax
$('#mole').html(data);
}
});
});
</script>

First, we need to add a timeout to the ajax handler so it will cancel the request after 5 seconds (here we use 5000 for milliseconds). Then, based on the docs, head to error and you can see the second param is textStatus. If it was a timeout, this will be equal to "timeout". This is probably your easiest path to what you need to do. Update the error handler as needed for your functionality.
$(window).bind('popstate', function() {
var url = location.pathname + '?rel=tab';
$.ajax({
timeout: 5000,
url: url,
success: function(data) {
$('#mole').html(data);
},
error: function(jqXHR, textStatus) {
if (textStatus === 'timeout') {
// we know the ajax failed due to a timeout,
// do what you need here, below is an example.
window.location = url;
}
}
});
});

Ajax User Typing message for chat

I am trying to make a facebook style user typing system. But i have one question about keypress.
So my code is working fine but i want to change something else like keypress, keyup, paste ect.
I am using following javascript and ajax codes. In the following my ajax code is working like if ($.trim(updateval).length == 0) { send width notyping.php notyping.php posting 0 and the 0 is don't show typing message.
If if ($.trim(updateval).length > 13) { send with usertyping.php usertyping.php posting 1 and the 1 is show typing message.
The problem is here if user is stoped to wrire some message then it is everytime saying typing. What should I do to fix for it anyone can help me in this regard ?
All ajax and javascript code is here:
;
(function($) {
$.fn.extend({
donetyping: function(callback, timeout) {
timeout = timeout || 1000; // 1 second default timeout
var timeoutReference,
doneTyping = function(el) {
if (!timeoutReference) return;
timeoutReference = null;
callback.call(el);
};
return this.each(function(i, el) {
var $el = $(el);
// Chrome Fix (Use keyup over keypress to detect backspace)
// thank you #palerdot
$el.is(':input') && $el.is(':input') && $el.on('keyup keypress paste', function(e) {
// This catches the backspace button in chrome, but also prevents
// the event from triggering too premptively. Without this line,
// using tab/shift+tab will make the focused element fire the callback.
if (e.type == 'keypress' && e.keyCode != 8) return;
// Check if timeout has been set. If it has, "reset" the clock and
// start over again.
if (timeoutReference) clearTimeout(timeoutReference);
timeoutReference = setTimeout(function() {
// if we made it here, our timeout has elapsed. Fire the
// callback
doneTyping(el);
}, timeout);
}).on('blur', function() {
// If we can, fire the event since we're leaving the field
doneTyping(el);
});
});
}
});
})(jQuery);
Checking text value if is 0 then send data is 0 for user no typing
$('#chattextarea').donetyping(function() {
var typingval = $("#chattextarea").val();
var tpy = $('#tpy').val();
if ($.trim(typingval).length == 0) {
$.ajax({
type: "POST",
url: "/notyping.php",
data: {
tpy: tpy
},
success: function(data) {
}
});
}
Checking text value is >13 then send data is 1 for user typing.(Maybe need to change this if statement)
if ($.trim(typingval).length > 13) {
$.ajax({
type: "POST",
url: "/usertyping.php",
data: {
tpy: tpy
},
success: function(data) {
}
});
}
});
Check and show user typing:
function getTyping(){
setInterval(function(){
var tpy = $('#tpy').val();
$.ajax({
type: "POST",
url: "/getTyping.php",
data: { tpy: tpy },
success: function(data) {
$('#s').html(data);
}
});
},1000);
}
getTyping();
HTML
<textarea id="chattextarea"></textarea>
<div id="s"></div>

I have some remarks about your code and app :
At the first, and as mentioned by #rory-mccrossan, unless you have the infrastructure of facebook, google or microsoft, ..., I think it's really a bad idea to use Ajax instead of Websockets for a real time application like a chat.
Now about your code, I don't know what your PHP scripts are doing behind the scene, but I think that you don't need to send two requests to indicate that the user is typing or not, you can limit that to one request to be sent when the user is typing otherwise, he is surely not typing. Of course you can use some sort of a timeout in your getTyping.php script to limit the life time of a "typing" status (for example 5 seconds), so if a request is sent after that timeout, you can know that your user is not typing.
And about your current problem, I think that's because the "not typing" status is just fired when the textarea is empty, so of course, after stopping writing and the length of the current text is more that 13, so the "not typing" status will never be fired (sent), that's why you need a timeout as I told you in the 2nd point ...
Also, don't forget the cache problem when getting the status using the getTyping.php script which should be not cacheable (or at least for a very limited period) ...
Then, I don't see in your posted code any information(s) to identify the current user and the one which is converting with him ... maybe you haven't included that in the question, I don't know !
...
Hope that can help.

My suggestion here to have external setInterval which will each 3 seconds save current text in oldValue variable and compare currentText with oldValue if they are equal then user stopped writing then send ajax to notyping.php

your updated code is given below
i have created a getTyping function which will be call at every time 1 sec interval if user get start typing.
in get getTyping setinterval function i called a function check_which_function.
in function check_which_funciton i used your code by applying conditions on textarea value length which is in nested if else statement , so now
if user start typing but if content length is =0 than
$.trim(typingval).length == 0 will execute till length is not equal to 12
if length of content is greather equal to 13 than
$.trim(typingval).length > 13 will execute
by default getTyping2() function is executing in this function getTyping.php ajax call is going
<script>
(function ($) {
$.fn.extend({
donetyping: function (callback, timeout) {
timeout = timeout || 1000; // 1 second default timeout
var timeoutReference,
doneTyping = function (el) {
if (!timeoutReference)
return;
timeoutReference = null;
callback.call(el);
};
return this.each(function (i, el) {
var $el = $(el);
// Chrome Fix (Use keyup over keypress to detect backspace)
// thank you #palerdot
$el.is(':input') && $el.is(':input') && $el.on('keyup keypress paste', function (e) {
// This catches the backspace button in chrome, but also prevents
// the event from triggering too premptively. Without this line,
// using tab/shift+tab will make the focused element fire the callback.
if (e.type == 'keypress' && e.keyCode != 8)
return;
// Check if timeout has been set. If it has, "reset" the clock and
// start over again.
if (timeoutReference)
clearTimeout(timeoutReference);
timeoutReference = setTimeout(function () {
// if we made it here, our timeout has elapsed. Fire the
// callback
doneTyping(el);
}, timeout);
}).on('blur', function () {
// If we can, fire the event since we're leaving the field
doneTyping(el);
});
});
}
});
})(jQuery);
function getTyping2() {
var tpy = $('#tpy').val();
$.ajax({
type: "POST",
url: "/getTyping.php",
data: {tpy: tpy},
success: function (data) {
$('#s').html(data);
}
});
}
function check_which_action() {
$('#chattextarea').donetyping(function () {
var typingval = $("#chattextarea").val();
var tpy = $('#tpy').val();
if ($.trim(typingval).length == 0) {
$.ajax({
type: "POST",
url: "/notyping.php",
data: {
tpy: tpy
},
success: function (data) {
}
});
}
else if ($.trim(typingval).length > 13) {
$.ajax({
type: "POST",
url: "/usertyping.php",
data: {
tpy: tpy
},
success: function (data) {
}
});
}
else {
getTyping2() ;
}
});
}
function getTyping() {
setInterval(check_which_action, 1000);
}
getTyping();
</script>
<textarea id="chattextarea"></textarea>
<div id="s"></div>

Rate-limiting AJAX requests for updating content to avoid duplicates

I'm trying to fetch posts dynamically using AJAX and JQuery by checking if the user is close to the bottom. Serverside is in python on GAE.
Listening for scroll:
this.config.window.on('scroll',this.loadContent);
1.Checking for distance from bottom
2.Sending an ajax request with the number of current posts in order to retrieve the next 10
3.results.check = true means that the server has no further posts to send.
loadContent: function(){
// 1
if($(document).height() - $(window).height() - $(window).scrollTop() < 1000) {
var posts = $('.troll').children('div').length;
data = 'loadmore=True&offset=' + posts; //2
$.ajax({
url: '/',
type: 'POST',
data: data,
dataType: 'json',
success: function(results){
if (results.check === 'true'){ //3
$(window).unbind('scroll');
return;
}
Post.insert10Values(results);
}
});
};
},
insert10Values: function(results){
var update = Handlebars.compile($('#troll10').html()),
troll10update = update(results);
$('div.troll').append( troll10update );
}
The problem here is that when scrolling fast, two or more requests are sent to the server and i get duplicate entries. I want to rate-limit on client-side.

Set a flag loading = false. Before you send a request, check the flag. If it's false, set the flag to true and proceed with request, otherwise ignore the event. When results arrive, show them and set the flag back to false.

Part of your problem is scroll event will trigger many times a second
you can throttle any function calls doing something like this:
var scrollTimer=false;
var delay=500; /* 1/2 second*/
$(window).on('scroll',function(){
if( scrollTimer){
clearTimeout( scrollTimer);
}
scrollTimer=setTimeout(function(){
/* run your code here*/
}, delay);
});
As for the ajax you could store a time for last ajax call and set a miniumum difference based on now vs stored time before making a new ajax call
var lastAJAX=Date.now(), AJAXMin=5000;/* 5 seconds*/
function checkAJAXCalls(){
var now=Date.now(), diff=now-lastAJAX;
if( diff >= AJAXMin){
lastAJAX=now;
return true;
}else{
return false;
}
}
Then run if(checkAJAXCalls()) prior to making request. Concept could be modified to update lastAJAX in success callback of $.ajax also

jQuery.ajax has a method called beforeSend. It is executed right before your ajax call. You can use it to check if any other request is in progress and cancel the call if there is one. If you return false in beforeSend function, the ajax call will not be fired so you won't have any duplicate content.
$.ajax({
url: '/',
type: 'POST',
data: data,
dataType: 'json',
beforeSend: function() {
if (window.nextPageProcess) {
return false;
} else {
window.nextPageProcess = 1;
}
},
success: function(results){
if (results.check === 'true'){ //3
$(window).unbind('scroll');
return;
}
Post.insert10Values(results);
window.nextPageProcess = 1;
}
});

Best Practise to check Internet connection in javascript

I am using Ajax to check my internet connection after every few second for my application which is using IE instance. But due to low bandwidth my internet explorer is crashing.
What best practise can be followed to check the internet connection so that it prevent crashing of internet explorer and boost performance ?
I am using the following code to check my internet connection.
The explanation of which is given at: -
http://tomriley.net/blog/archives/111 from where I get the jquery file.
(function ($) {
$.fn.checkNet = function (intCheckInterval, strCheckURL) {
if (typeof (intCheckInterval) === 'undefined') {
var intCheckInterval = 5
} if (typeof (strCheckURL) === 'undefined') {
var strCheckURL = window.location
} else if (strCheckURL.indexOf('http') === -1) {
var strCheckURL = 'http://' + strCheckURL
} intCheckInterval = intCheckInterval * 1000; function doRequest(strCheckURL) {
$.ajax({ url: strCheckURL, cache: false, success: function () {
if ($('#netWarn').length) {
$('#netWarn').fadeOut()
} $('.tempDisabled').removeAttr('disabled').removeClass('tempDisabled')
}, error: function () {
if (!$('#netWarn').length) {
$('body').prepend('<p id="netWarn">No internet connection detected, some features will be re-enabled when a connection is detected. </p>'); $('#netWarn').fadeIn()
}
}
})
} setInterval(function () {
doRequest(strCheckURL)
}, intCheckInterval)
}
})(jQuery);

my plugin takes an argument for the length of time between the requests. So, if you want a 10sec interval between requests, call it with this code:
$.fn.checkNet(10);
...after you've included the plugin. I uploaded a new version recently which works much more efficiently.

How to update Ajax call (not content)

Look at this code please - how could I kill / update or restart an ajax call (not content that Ajax calls) after the content has already been called?
I mean the $('#posting_main') is called onclick and animated - how to stop ajax and make it another $('#posting_main') on another click?
$(document).ready(function() {
$("#img_x_ok").click(function(e){
e.preventDefault();
var post_text = $.trim($("#main_text_area").val());
var data_text = 'post_text='+ post_text;
if (post_text === "") return;
var xhr = $.ajax({
type: "POST",
url: "comm_main_post.php",
data: data_text,
cache: false,
success: function (data){
//content
$("#posting_main").fadeIn();
$("#posting_main").load("pull_comm.php");
$("#main_text_area").attr("value", "");
$("#posting_main").animate({
marginTop: "+=130px",
}, 1000 );
}
}); //ajax close
}); }); //both functions close

You can abort the current request with:
xhr.abort();
After having done that, you can run another $.ajax(...) to make a second request.
You could implement it like the following. Note that indenting code makes it a lot more readable!
$(document).ready(function() {
var xhr; // by placing it outside the click handler, you don't create
// a new xhr each time. Rather, you can access the previous xhr
// and overwrite it this way
$("#img_x_ok").click(function(e){
e.preventDefault();
var post_text = $.trim($("#main_text_area").val());
var data_text = 'post_text='+ post_text;
if (post_text === "") return;
if(xhr) xhr.abort(); // abort current xhr if there is one
xhr = $.ajax({
type: "POST",
url: "comm_main_post.php",
data: data_text,
cache: false,
success: function (data){
//content
$("#posting_main").fadeIn();
$("#posting_main").load("pull_comm.php");
$("#main_text_area").attr("value", "");
$("#posting_main").animate({
marginTop: "+=130px",
}, 1000 );
}
});
});
});

I am not sure I fully understand your question, however:
xhr.abort() will kill the AJAX request. After calling abort(), you could modify and resend the request, if desired.
$("#posting_main").stop() will stop the fadeIn animation. (And I think you might need to follow that with $("#posting_main").hide() to be sure it isn't left partially visible.)