Ajax Request gets blocked in Firebug but works in Genymotion. Why? - ajax

I am trying to build an "app version" of my website (a social network).
I am using PhoneGap + jQuery Mobile (i started learning them today).
The app simply needs to retrieve new posts from the website and show them to the user. Therefore I thought a simple Ajax Request would do the job.
So, i created a php test file on the server (URL: http://www.racebooking.net/it/moto/app/get_post_test.php), which simply Echoes Alien contact SUCCESS!
I've made a simple html page in localhost (on my PC) called index.html with a div called #post-container and an AJAX request:
var root = "http://www.racebooking.net/it/moto"
$.get(root + "/app/get_post_test.php", function(data){
$("#posts-container").html(data);
});
If everything is correct, i expect to see Alien contact SUCCESS! in the post-content div.
What happens looks strange:
If i run the app from eclipse using Genymotion, everything works fine
and i see the message Alien contact SUCCESS! -> the AJAX request
went fine
If i open the index.html file on firefox, i don't see anything
and FireBug informs me that the cross-origin request was blocked.
He also tells me to activate CORS.
1) Why is that happening and how can i make FireBug work (which is better and faster for debugging)?
2) Am i following the right procedure or i am missing something?

I found the solution from this post.
I just needed to add header('Access-Control-Allow-Origin: *'); at the top of my php file.

Related

ajax returns page source, not the message

All the answers I saw here or elsewhere on Google were with jquery. This is not jquery.
I send an ajax string to a php file.
The php, among other things, formulates a message string which I echo
back to the client.
The returned string is put up in the client as an alert.
The form is then reset.
The problem is that when I do this it puts up as much of the page source that the alert can handle. If I open developer tools to look at the return, it puts the message up correctly, not the page source. Here is the return snippet in my ajax:
ajaxRequest.onreadystatechange = function(){
if(ajaxRequest.readyState == 4){
alert(ajaxRequest.responseText);
document.getElementById("thisForm").reset();
}
}
The php file does a simple echo of a text string.
What is it about developer tools that makes this run correctly and why doesn't it print out the message in the alert when developer tools is not there?
When I run the backend php by itself, with or without developer tools, it displays the message properly.
Does anyone have any ideas?
More information: I tried to replace the alert and reset with a
display.innerHTML=ajaxRequest.responseText where display is a javascript object formed from getElementById("ajaxReturn") of a "div id="ajaxReturn". It didn't work. When I tried developer tools, it showed the network response text as being the page source.
I also added && this.status == 200 to the if statement. No change.
The problem is solved. I am not deleting this because it might help some other poster who runs into the same problem. I launched the AJAX with an onclick to a javascript function called ajaxFunction(). The html entity containing the onclick had an href="#" in it. Removing that href solved the problem.
I had the exact same issue and my cause was related to having an extra slash in my URL.
Lets say my URL was:
https://example.com/index.php
I had a wrong link as follows:
https://example.com/index.php/
On both instances my server loads the page,
But the Ajax shows the page source as response for:
https://example.com/index.php/
But works fine for:
https://example.com/index.php
The ajax is essentially posting to index.php/ajaxpage.php which then responds with whats on index.php instead of whats on ajaxpage.php

How to debug AJAX (POST) with PhpStorm and Xdebug?

I have configured PhpStorm to debug HTTP GET - but only when I load a page directly.
When I want to debug AJAX, I take the URL which my JS would request and create a PhpStorm configuration to debug it.
Not particularly elegant, is it?
And, of course, I can't do that for POST requests (or can I?).
Ideally, I would like to load my AngularJs app in the browser (Chrome) and be able to breakpoint and debug the backend in PhpStorm.
I googled a lot, and found much that came close, but I can't find the answer :-(
Who can help?
[Update] a few years later, and I am using the excellent and free Postman to test both GET and POST.
If Xdebug and PHPStorm are configured to debug HTTP GET when loading a page normally, then simply include the GET parameter in the URL of the AJAX request in your Javascript. For example: http://example.com/script.php?XDEBUG_SESSION_START=PHPSTORM
Turn on Debug listening in PHPStorm, send the AJAX request with the new URL, and the debugger should catch it. The POST data you are looking for should appear in $_POST as usual.
I am using kind of hacking method to debug AJAX requests. My project is Laravel. You can change this code as compatible with your technology.
Basic idea is:
Grab home page debug port
Create a session
Using this session concatenate the AJAX url
When you start debugging, the port will be applied for all ajax urls which having + debug_url.
HomeController#index method
// Development purpose only
if ($request->has('XDEBUG_SESSION_START')) $request->session()->put('debug_port' , $request->get('XDEBUG_SESSION_START'));
master.blade.php
<script>
var debug_url='?XDEBUG_SESSION_START={{session('debug_port')}}';
</script>
submit.blade.php
<script>
$.ajax(url + debug_url, {
method:'post',
data:{}
});
</script>

Rendering issue after AJAX call

I'm using Bottle microframework (but I doubt my issue comes from it)
First if I define a simple redirect from /test_redirect to /x it works. So Bottle redirect() on simple case works.
Now I have a page /buy that uses Stripe Checkout (custom form) pointing to my server /stripe_process
Basically Stripe Checkout verifies credit card transaction, creates a token and POST it to my /stripe_process.
/stripe_process does its stuff (calling Stripe to charge the card) then when transaction is success, i use instruct Bottle to:
redirect('/transaction_summary')
My webserver logs show that indeed /transaction_summary is called and server-side script is processed (I put flags in my script to check this), and its template is returned (browser 'Network' analysis gives a 303 then a 200 on /transaction_summary, I even get the correct response data: seems 100% normal), but on the browser page nothing happens (I still have my initial page /buy in url field, instead of having been redirected to /transaction_summary): browser received the /transaction_summary response, a preview is visible on Chrome devtools preview mode, but is not displaying it!
Also if in /stripe_process I change redirect() with a simple return template(), same issue: no data is processed by the browser.
Any clue ? This behaviour have been observed on 100% my tests:
- Firefox / Windows
- Chrome / iOS 9 (iPad)
- Chrome / linux
- Iceweasel / linux
- Chrome / Android
- Chrome / OSX
I suspect it has something to do with Stripe Checkout taking over something (since redirect() works perfectly in my simple test), but I can't figure the reason and how to solve this.
If from Chrome-devtools-network section I go to last action (ie /transaction_summary download) and open /transaction_summary in new tab, it renders perfectly.
So it's not a bottle problem, nor webserver. I suspect more on Stripe checkout modal/popup behaviour
$(window).on('popstate', function() { handler.close(); }); is present as stripe docs instruct but anyway stripe_handler is properly closed after token received (I checked with handler.closed callback...)
EDIT:
If I replace redirect() with straight return template(), same issue: html stuff is downloaded by the browser, avail on preview, but not rendered on main window.
EDIT2:
if I add on my page a href to /test_redirect redirecting to /x it works.
Note that this manual redirect work after Stripe checkout. The only difference with Stripe sequence here is user interaction ('click' on href) but as my redirect is same domain, browsers shouldn't block redirect anyway.
Problem was that AJAX call used to send Stripe token to /stripe_process was handling redirect response. That's why on network I had 200 answer from webserver but all html page data was going into the AJAX callback and rendered. Thanks to Thomas for raising my nose from this issue.
Solution is /stripe_process to return 1 in case of success (instead of server-side redireciton), then make the redirection from AJAX success callback.

Angular JS $http request does not reach the server in ie8

I'm having issues with using $http on ie8. The request does not reach the server, until I hit a refresh. Coming back to the same link still has the same problem until I hit refresh again.
The weird thing is if the web server is on LAN and the request is made to a server in LAN, it works fine. But if the webserver is hosted remotely, it does not work!
Here is the code:
Index.html
{{test}}
Controller
app.controller(
"TestController",
function( $scope, $http) {
var url = '/test/get_data';
$http.get(url).success(function(data) {
$scope.test = data;
});
}
);
I got this error: TypeError: Object doesn't support this property or methodundefined
I prepared a JSFiddle earlier but JSFiddle is broken in ie8 so I don't provide it here.
Unfortunately I don't have a remote server that I can share with you.
Edit
Previously I used an external url which gave me 'Access Denied' error in ie because of Same Origin Policy as mentioned by one answer below. But this was not my original problem. I still have the issue above when request is from the same origin
This is a cross domain request, which is not allowed in ajax because of Same Origin Policy.
There are two solutions for this
1. JSONP: It is a cross browser way to handle cross domain ajax requests using javascript callback mechanism
2. CORS: It is a HTML5 standard, it is implemented by most of the modern browsers except IE
Mongodb lab is not supporting jsonp since it has support for CORS, that is why your request is failing in IE and works in Chrome and other browsers.
As per this post they do not have any plan to support jsonp, so I don't thick there is a way to make this work in IE.
So I found the fix... Hope this helps anyone out there that experience this problem
Angular script needs to be loaded after jQuery. I didn't have this because Yii framework that I use autoloads jQuery and the angular was not included after the jQuery.
All the controller functions need to be at the end of body section (just before the closing )
Updating to angular 1.0.5 seems to fix the problem. The problem occurred in 1.0.4 with all the above tricks. I think is related to fix 791804bd

What does status=canceled for a resource mean in Chrome Developer Tools?

What would cause a page to be canceled? I have a screenshot of the Chrome Developer Tools.
This happens often but not every time. It seems like once some other resources are cached, a page refresh will load the LeftPane.aspx. And what's really odd is this only happens in Google Chrome, not Internet Explorer 8. Any ideas why Chrome would cancel a request?
We fought a similar problem where Chrome was canceling requests to load things within frames or iframes, but only intermittently and it seemed dependent on the computer and/or the speed of the internet connection.
This information is a few months out of date, but I built Chromium from scratch, dug through the source to find all the places where requests could get cancelled, and slapped breakpoints on all of them to debug. From memory, the only places where Chrome will cancel a request:
The DOM element that caused the request to be made got deleted (i.e. an IMG is being loaded, but before the load happened, you deleted the IMG node)
You did something that made loading the data unnecessary. (i.e. you started loading a iframe, then changed the src or overwrite the contents)
There are lots of requests going to the same server, and a network problem on earlier requests showed that subsequent requests weren't going to work (DNS lookup error, earlier (same) request resulted e.g. HTTP 400 error code, etc)
In our case we finally traced it down to one frame trying to append HTML to another frame, that sometimes happened before the destination frame even loaded. Once you touch the contents of an iframe, it can no longer load the resource into it (how would it know where to put it?) so it cancels the request.
status=canceled may happen also on ajax requests on JavaScript events:
<script>
$("#call_ajax").on("click", function(event){
$.ajax({
...
});
});
</script>
<button id="call_ajax">call</button>
The event successfully sends the request, but is is canceled then (but processed by the server). The reason is, the elements submit forms on click events, no matter if you make any ajax requests on the same click event.
To prevent request from being cancelled, JavaScript event.preventDefault(); have to be called:
<script>
$("#call_ajax").on("click", function(event){
event.preventDefault();
$.ajax({
...
});
});
</script>
NB: Make sure you don't have any wrapping form elements.
I had a similar issue where my button with onclick={} was wrapped in a form element. When clicking the button the form is also submitted, and that messed it all up...
Another thing to look out for could be the AdBlock extension, or extensions in general.
But "a lot" of people have AdBlock....
To rule out extension(s) open a new tab in incognito making sure that "allow in incognito is off" for the extention(s) you want to test.
In my case, I found that it is jquery global timeout settings, a jquery plugin setup global timeout to 500ms, so that when the request exceed 500ms, chrome will cancel the request.
You might want to check the "X-Frame-Options" header tag. If its set to SAMEORIGIN or DENY then the iFrame insertion will be canceled by Chrome (and other browsers) per the spec.
Also, note that some browsers support the ALLOW-FROM setting but Chrome does not.
To resolve this, you will need to remove the "X-Frame-Options" header tag. This could leave you open to clickjacking attacks so you will need to decide what the risks are and how to mitigate them.
Here's what happened to me: the server was returning a malformed "Location" header for a 302 redirect.
Chrome failed to tell me this, of course. I opened the page in firefox, and immediately discovered the problem.
Nice to have multiple tools :)
Another place we've encountered the (canceled) status is in a particular TLS certificate misconfiguration. If a site such as https://www.example.com is misconfigured such that the certificate does not include the www. but is valid for https://example.com, chrome will cancel this request and automatically redirect to the latter site. This is not the case for Firefox.
Currently valid example: https://www.pthree.org/
A cancelled request happened to me when redirecting between secure and non-secure pages on separate domains within an iframe. The redirected request showed in dev tools as a "cancelled" request.
I have a page with an iframe containing a form hosted by my payment gateway. When the form in the iframe was submitted, the payment gateway would redirect back to a URL on my server. The redirect recently stopped working and ended up as a "cancelled" request instead.
It seems that Chrome (I was using Windows 7 Chrome 30.0.1599.101) no longer allowed a redirect within the iframe to go to a non-secure page on a separate domain. To fix it, I just made sure any redirected requests in the iframe were always sent to secure URLs.
When I created a simpler test page with only an iframe, there was a warning in the console (which I had previous missed or maybe didn't show up):
[Blocked] The page at https://mydomain.com/Payment/EnterDetails ran insecure content from http://mydomain.com/Payment/Success
The redirect turned into a cancelled request in Chrome on PC, Mac and Android. I don't know if it is specific to my website setup (SagePay Low Profile) or if something has changed in Chrome.
Chrome Version 33.0.1750.154 m consistently cancels image loads if I am using the Mobile Emulation pointed at my localhost; specifically with User Agent spoofing on (vs. just Screen settings).
When I turn User Agent spoofing off; image requests aren't canceled, I see the images.
I still don't understand why; in the former case, where the request is cancelled the Request Headers (CAUTION: Provisional headers are shown) have only
Accept
Cache-Control
Pragma
Referer
User-Agent
In the latter case, all of those plus others like:
Cookie
Connection
Host
Accept-Encoding
Accept-Language
Shrug
I got this error in Chrome when I redirected via JavaScript:
<script>
window.location.href = "devhost:88/somepage";
</script>
As you see I forgot the 'http://'. After I added it, it worked.
Here is another case of request being canceled by chrome, which I just encountered, which is not covered by any of answers up there.
In a nutshell
Self-signed certificate not being trusted on my android phone.
Details
We are in development/debug phase. The url is pointing to a self-signed host. The code is like:
location.href = 'https://some.host.com/some/path'
Chrome just canceled the request silently, leaving no clue for newbie to web development like myself to fix the issue. Once I downloaded and installed the certificate using the android phone the issue is gone.
If you use axios it can help you
// change timeout delay:
instance.defaults.timeout = 2500;
https://github.com/axios/axios#config-order-of-precedence
For my case, I had an anchor with click event like
<a href="" onclick="somemethod($index, hour, $event)">
Inside click event I had some network call, Chrome cancelling the request. The anchor has href with "" means, it reloads the page and the same time it has click event with network call that gets cancelled. Whenever i replace the href with void like
<a href="javascript:void(0)" onclick="somemethod($index, hour, $event)">
The problem went away!
If you make use of some Observable-based HTTP requests like those built-in in Angular (2+), then the HTTP request can be canceled when observable gets canceled (common thing when you're using RxJS 6 switchMap operator to combine the streams). In most cases it's enough to use mergeMap operator instead, if you want the request to complete.
I had faced the same issue, somewhere deep in our code we had this pseudocode:
create an iframe
onload of iframe submit a form
After 2 seconds, remove the iframe
thus, when the server takes more than 2 seconds to respond the iframe to which the server was writing the response to, was removed, but the response was still to be written , but there was no iframe to write , thus chrome cancelled the request, thus to avoid this I made sure that the iframe is removed only after the response is over, or you can change the target to "_blank".
Thus one of the reason is:
when the resource(iframe in my case) that you are writing something in, is removed or deleted before you stop writing to it, the request will be cancelled
I have embedded all types of font as well as woff, woff2, ttf when I embed a web font in style sheet. Recently I noticed that Chrome cancels request to ttf and woff when woff2 is present. I use Chrome version 66.0.3359.181 right now but I am not sure when Chrome started canceling of extra font types.
We had this problem having tag <button> in the form, that was supposed to send ajax request from js. But this request was canceled, due to browser, that sends form automatically on any click on button inside the form.
So if you realy want to use button instead of regular div or span on the page, and you want to send form throw js - you should setup a listener with preventDefault function.
e.g.
$('button').on('click', function(e){
e.preventDefault();
//do ajax
$.ajax({
...
});
})
I had the exact same thing with two CSS files that were stored in another folder outside my main css folder. I'm using Expression Engine and found that the issue was in the rules in my htaccess file. I just added the folder to one of my conditions and it fixed it. Here's an example:
RewriteCond %{REQUEST_URI} !(images|css|js|new_folder|favicon.ico)
So it might be worth you checking your htaccess file for any potential conflicts
happened to me the same when calling a. js file with $. ajax, and make an ajax request, what I did was call normally.
In my case the code to show e-mail client window caused Chrome to stop loading images:
document.location.href = mailToLink;
moving it to $(window).load(function () {...}) instead of $(function () {...}) helped.
In can this helps anybody I came across the cancelled status when I left out the return false; in the form submit. This caused the ajax send to be immediately followed by the submit action, which overwrote the current page. The code is shown below, with the important return false at the end.
$('form').submit(function() {
$.validator.unobtrusive.parse($('form'));
var data = $('form').serialize();
data.__RequestVerificationToken = $('input[name=__RequestVerificationToken]').val();
if ($('form').valid()) {
$.ajax({
url: this.action,
type: 'POST',
data: data,
success: submitSuccess,
fail: submitFailed
});
}
return false; //needed to stop default form submit action
});
Hope that helps someone.
For anyone coming from LoopbackJS and attempting to use the custom stream method like provided in their chart example. I was getting this error using a PersistedModel, switching to a basic Model fixed my issue of the eventsource status cancelling out.
Again, this is specifically for the loopback api. And since this is a top answer and top on google i figured i'de throw this in the mix of answers.
For me 'canceled' status was because the file did not exist. Strange why chrome does not show 404.
It was as simple as an incorrect path for me. I would suggest the first step in debugging would be to see if you can load the file independently of ajax etc.
The requests might have been blocked by a tracking protection plugin.
It happened to me when loading 300 images as background images. I'm guessing once first one timed out, it cancelled all the rest, or reached max concurrent request. need to implement a 5-at-a-time
One the reasons could be that the XMLHttpRequest.abort() was called somewhere in the code, in this case, the request will have the cancelled status in the Chrome Developer tools Network tab.
In my case, it started coming after chrome 76 update.
Due to some issue in my JS code, window.location was getting updated multiple times which resulted in canceling previous request.
Although the issue was present from before, chrome started cancelling request after update to version 76.
I had the same issue when updating a record. Inside the save() i was prepping the rawdata taken from the form to match the database format (doing a lot of mapping of enums values, etc), and this intermittently cancels the put request. i resolved it by taking out the data prepping from the save() and creating a dedicated dataPrep() method out of it. I turned this dataPrep into async and await all the memory intensive data conversion. I then return the prepped data to the save() method that i could use in the http put client. I made sure i await on dataPrep() before calling the put method:
await dataToUpdate = await dataPrep();
http.put(apiUrl, dataToUpdate);
This solved the intermittent cancelling of request.

Resources