I have a PhoneGap project and lately I've been been hitting a lot of random "status 0" results. I can literally try the same end-point 10 times in a row, passing the same post parameters, and the status will flip between a 200 and a 0. In both cases, the results return almost instantly - it is not a timeout issue.
I'm using PhoneGap in iOS, if the platform is a factor. Does anyone have any ideas on where to start looking?
FYI - I implemented the tip at Ajax https call in ios using PhoneGap not working?. At first I thought it helped, but perhaps it was just a run of good luck.
It is perfectly normal to get a status of 0 when requesting a URL over AJAX. Since some browsers will return a 0 on a CORS request but since you are doing your request from the file:// protocol CORS does not apply. When I do a AJAX request I take 200 and 0 as a success.
Related
Earlier, chrome upgrading to version 48.
Some never before had a problem (in earlier versions, such as 47), such as pages and ajax request can not return data.
Start ajax request is no response, return "this request has no preview available", but only the individual ajax request, there is a page has five ajax request, only one of the two ajax no return, but the remaining three one can work.
Today, we found that the request pages directly blocking the entire page could not be loaded.
Or more, on Firefox no problems, normal page, ajax request properly.
I began to wonder whether it is after you upgrade to chrome version 48, in order to reduce memory consumption, blocking part of a normal request.
So, does anybody know the cause of the problem and how to avoid this problem.
ok,48.0.2564.103 m has fix it.
just see Comment 16 in
Sync ajax call get 200 code but empty body when the server returns 304 Not Modified
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.
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
I am using the Prototype JS framework to do Ajax calls. Here is my code:
new Ajax.Request( '/myurl.php', {method: 'post', postBody: 'id='+id+'&v='+foo, onSuccess: success, onFailure: failed} );
function success(ret) {
console.log("success",ret.readyState, ret.status);
}
function failed(ret) {
console.log("failed",ret.readyState, ret.status);
}
Most of the time, this works fine and the success function is called with a status code of 200. About 5% of the time on Safari the success function is called with a status code of 0. In this case, when I look in the Network tab of the web inspector, the ajax call is listed with a status of "canceled". I can confirm with server logs, that the request never hit the server. It's as if the ajax request was immediately canceled without even trying to connect to the server. I have not found any reliable way to reproduce this, it seems to be random. I do it 20 times and it happens once.
Does anyone know what would cause the ajax call to get canceled or return a status code of 0?
The cause may be the combination of http server and browser you are using. It doesn't seems like an error of the PrototypeJS library.
Multiple sources states that keep-alive parameter of the HTTP connection seems to be broken in Safari (see here, here or here). On Apache, they recommend adding this to the configuration:
BrowserMatch "Safari" nokeepalive
(Please check the appropriate syntax in your server documentation).
If Safari handles badly HTTP persistent connections with your server, it may explain what you experiences.
If it's not too complex for you, I would try another HTTP server, there are plenty available on every OS.
We lack a bit of information to answer fully your answer, though. The server issue is a lead but there may be others. It would be nice to know if it does the same thing in other browsers (Firefox with Firebug will display this kind of information, Chrome, Opera and IE have development builtin toolboxes). Another valid question would be how often you execute this AJAX request per second (if relevant).
I know this is an old topic, but I wanted to share a solution for Safari that might save others some time. The following line really solved all problems:
BrowserMatch "^(?=.*Safari)(?=.*Macintosh)(?!.*Chrom).*" nokeepalive gzip-only-text/html
The regex makes sure only Safari on Mac is detected, and not Mobile Safari and Chrome(ium) and such. Safari for Windows is also not matched, but the keepalive problem seems to be a Mac-Safari combination only. In addition, some Safari versions do not handle gzipped css/js well.
All our symptoms of our site crashing or CSS not completley loading in different versions of Safari which caused me to nearly pull my hair out (Safari really is the new IE) have been solved for us with this Apache 'configuration hack'.
I'm writing a small app that will be used to monitor the status of a few websites, mainly just to report which websites are online and which websites are offline.
I currently have this code as the onreadystatechange function:
if(xmlhttp.readyState == 4) {
if (xmlhttp.status == 200) {
element(id).innerHTML = "Online";
}
else {
element(id).innerHTML = "Offline";
}
}
It runs properly when the website is online, but it never reaches the 'else' block if I do an AJAX request on a website that is offline.. I'm thinking the request never reaches readyState 4 if the website is down?
Any suggestions for how to capture an AJAX request to an offline website?
What you will want to do is abort the request after a specific amount of time, i.e. a timeout. Here's an article that should help:
Async Requests over an Unreliable Network
IE8's XHR object supports an ontimeout event (http://msdn.microsoft.com/en-us/library/cc197061(VS.85).aspx)
ReadyState=4 means "loaded", which won't happen if the content doesn't load.
I just tested now using Fiddler, and it returned Status 502, Body 512
You can check the header for a 404 error.