I don't know if this is a duplicate post or not, sorry if it is. I'm using jquery.getJSON to load a json on my server which works just fine. Although, if I try and load a json file on a different server it doesn't work. I know I don't have any code here (because there's not much point) but I just want to know if I'm using it wrong or if it isn't supposed to load external files. I'm using the iOS Safari browser if that effects anything.
EDIT: I've looked at the console (idk what the error thing really means, it's just red with an x by the url it's trying to get the json from) and it looks like it's not actually receiving the data. Plus, do remember I'm on iOS, not desktop so I couldn't look at the console in the "Develop tab :P
EDIT 2: Great! I think I got it working! http://skitty.xyz/getJSON/
You're most likely encountering a path issue; the purpose of $.getJSON is to acquire data via http GET request so yes, it is intended to work remotely. To diagnose your issue, make certain you can access the json file in your browser first: http://domain.com/my_data.json. If that works, use that as the URL you pass into $.getJSON:
$.getJSON( 'http://domain.com/my_data.json', function(data) {
// do something with your data
});
http://api.jquery.com/jquery.getjson/
jquery.getJSON uses ajax which is all about external resources. Here's a couple things to check for if it's not working on an external resource:
1: Is the path you specified correct? The usage is jquery.getJSON(path, callback). The path should be something you can just drop in your browser and see. If an incorrect path is your problem, you'll see a 404 in the console.
2: Is the resource http and your site https? Non-secure resources on secure pages will get blocked by browser security features. You'd see a error to this effect in the console.
3: Is CORS (Cross-origin resource sharing) enabled for your site on the external resource? Servers will sometimes use a whitelist of IPs and domains to determine what origins are allowed to make requests of it. You'd also see an error to this effect in the console.
There probably some other things to look for but this is where I'd start.
Also, by all means, use the debugging features of Safari to LQQK at the actual HTTP data-streams that are passing back-and-forth in response to what you're doing. (You might need to click on a preference to see the "Develop" menu, which will take you to "Show Web Inspector" and its Network tab.)
This approach will instantly answer many questions that a JavaScript-centered approach will not so-readily tell you. (And of course, you can look at the JavaScript console too ... and at the same time.) "The actual data streams, please." Safari will tell you "exactly what bytes" your app actually sent to the server, and "exactly what bytes" the server sent in return. "Priceless!™"
Are you saying you are using jquery ajax request to load some json data from a server?
check the "not working server" has the same end point as your server.
Check if the url you want to get data from is correct.
check if console logged any errors.
Also quote from http://api.jquery.com/jquery.getjson/
"Additional Notes:
Due to browser security restrictions, most "Ajax" requests are subject to the same origin policy; the request can not successfully retrieve data from a different domain, subdomain, port, or protocol.
Script and JSONP requests are not subject to the same origin policy restrictions."
On Chrome, I'm having no troubles making a cross domain request, however on Firefox (Ubuntu 14.04), I get an error that consists only of a colon on the line that calls for the xmlhttprequest.
xmlhttp.open("GET", "http://x.x.x.x:xxxx/folder/file.xml", false);
The error message is just ":".
Try Disabling AdBlock
I was having a similar issue where all of my XMLHttpRequests were going through except for a few very specific ones where even minor URL changes fixed the problem. And the only thing I was getting was a colon : in the console. In the end I realized that AdBlockPlus was blocking at least one these requests from going through (the request had 'Banners' in the URL).
So I'm not sure if this would have solved your problem, but I've encountered it multiple times.
using Firebug, the issue turned out to be
Blocked loading mixed active content
I had the same error on a CORS POST request.
I'm using https://cors-anywhere.herokuapp.com/ to bypass the Same-origin policy.
The problem was NoScript blocking the external domain, so in case you're using an external API in your request, this might solve it.
Same as this answer, however the problem for me isn't present neither with AdBlock nor with uBlock.
It's present with uMatrix.
You can find that it blocks the request at this URL:
chrome://umatrix/content/logger-ui.html
You can enable it manually when clicking on that field:
and choosing to enable XHR in the uMatrix popup:
The blocking persists even if you have the code packaged in an Add-on that's correctly installed (the blue bar containts Internal UUID of a Firefox Add-on), therefore if you've ever wondered why some Add-ons don't work while uMatrix (or likes) is enabled, this might be one of the reasons.
I mocking my API using Apiary.io. But somehow I cannot read any headers from response object using angularJS. And I am sure i have at least Content-Type: application/json correctly set-up by checking in firebug. Code in Angular should read headers correctly too as i can print them when sending request to somewhere else than apiary.io...
$http.get('http://ies.apiary.io/some').then(function(response) {
console.log("ok",response.headers('Content-Type'));
},function(response){console.log("err",response);});
http://plnkr.co/edit/zMO0pXGsIdJkV0fZdBdw
It all boils down to a bug in firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=608735
For CORS request, firefox is not returning anything for req.getAllRequestHeaders(), although req.getRequestHeader('Content-Type') returns properly.
Either FF bug has to be fixed or Angular must work around it (as jQuery does) or you must go deeper and use XmlHttpRequest instance directly.
This was maybe also related, but probably not the core issue:
However, few days ago, Apiary.io was not setting Max-Age in CORS headers. Thus, if you had a minimal blueprint, you might have CORS pre-flight response cached and thus subsequent requests may be disallowed even if you added additional resources to your blueprint.
Max-Age is now set to 10 seconds, so it should work properly. However, depending on your browser, pre-flight cache might still affect you. Try purging it or test this app in another browser.
I'm developing a page that pulls images from Flickr and Panoramio via jQuery's AJAX support.
The Flickr side is working fine, but when I try to $.get(url, callback) from Panoramio, I see an error in Chrome's console:
XMLHttpRequest cannot load http://www.panoramio.com/wapi/data/get_photos?v=1&key=dummykey&tag=test&offset=0&length=20&callback=processImages&minx=-30&miny=0&maxx=0&maxy=150. Origin null is not allowed by Access-Control-Allow-Origin.
If I query that URL from a browser directly it works fine. What is going on, and can I get around this? Am I composing my query incorrectly, or is this something that Panoramio does to hinder what I'm trying to do?
Google didn't turn up any useful matches on the error message.
EDIT
Here's some sample code that shows the problem:
$().ready(function () {
var url = 'http://www.panoramio.com/wapi/data/get_photos?v=1&key=dummykey&tag=test&offset=0&length=20&callback=processImages&minx=-30&miny=0&maxx=0&maxy=150';
$.get(url, function (jsonp) {
var processImages = function (data) {
alert('ok');
};
eval(jsonp);
});
});
You can run the example online.
EDIT 2
Thanks to Darin for his help with this. THE ABOVE CODE IS WRONG. Use this instead:
$().ready(function () {
var url = 'http://www.panoramio.com/wapi/data/get_photos?v=1&key=dummykey&tag=test&offset=0&length=20&minx=-30&miny=0&maxx=0&maxy=150&callback=?';
$.get(url, function (data) {
// can use 'data' in here...
});
});
For the record, as far as I can tell, you had two problems:
You weren't passing a "jsonp" type specifier to your $.get, so it was using an ordinary XMLHttpRequest. However, your browser supported CORS (Cross-Origin Resource Sharing) to allow cross-domain XMLHttpRequest if the server OKed it. That's where the Access-Control-Allow-Origin header came in.
I believe you mentioned you were running it from a file:// URL. There are two ways for CORS headers to signal that a cross-domain XHR is OK. One is to send Access-Control-Allow-Origin: * (which, if you were reaching Flickr via $.get, they must have been doing) while the other was to echo back the contents of the Origin header. However, file:// URLs produce a null Origin which can't be authorized via echo-back.
The first was solved in a roundabout way by Darin's suggestion to use $.getJSON. It does a little magic to change the request type from its default of "json" to "jsonp" if it sees the substring callback=? in the URL.
That solved the second by no longer trying to perform a CORS request from a file:// URL.
To clarify for other people, here are the simple troubleshooting instructions:
If you're trying to use JSONP, make sure one of the following is the case:
You're using $.get and set dataType to jsonp.
You're using $.getJSON and included callback=? in the URL.
If you're trying to do a cross-domain XMLHttpRequest via CORS...
Make sure you're testing via http://. Scripts running via file:// have limited support for CORS.
Make sure the browser actually supports CORS. (Opera and Internet Explorer are late to the party)
You need to maybe add a HEADER in your called script, here is what I had to do in PHP:
header('Access-Control-Allow-Origin: *');
More details in Cross domain AJAX ou services WEB (in French).
For a simple HTML project:
Python 2
cd project
python -m SimpleHTTPServer 8000
Python 3
cd project
python -m http.server 8000
Then browse your file.
Works for me on Google Chrome v5.0.375.127 (I get the alert):
$.get('http://www.panoramio.com/wapi/data/get_photos?v=1&key=dummykey&tag=test&offset=0&length=20&callback=?&minx=-30&miny=0&maxx=0&maxy=150',
function(json) {
alert(json.photos[1].photoUrl);
});
Also I would recommend you using the $.getJSON() method instead as the previous doesn't work on IE8 (at least on my machine):
$.getJSON('http://www.panoramio.com/wapi/data/get_photos?v=1&key=dummykey&tag=test&offset=0&length=20&callback=?&minx=-30&miny=0&maxx=0&maxy=150',
function(json) {
alert(json.photos[1].photoUrl);
});
You may try it online from here.
UPDATE:
Now that you have shown your code I can see the problem with it. You are having both an anonymous function and inline function but both will be called processImages. That's how jQuery's JSONP support works. Notice how I am defining the callback=? so that you can use an anonymous function. You may read more about it in the documentation.
Another remark is that you shouldn't call eval. The parameter passed to your anonymous function will already be parsed into JSON by jQuery.
As long as the requested server supports the JSON data format, use the JSONP (JSON Padding) interface. It allows you to make external domain requests without proxy servers or fancy header stuff.
If you are doing local testing or calling the file from something like file:// then you need to disable browser security.
On MAC:
open -a Google\ Chrome --args --disable-web-security
It's the same origin policy, you have to use a JSON-P interface or a proxy running on the same host.
We managed it via the http.conf file (edited and then restarted the HTTP service):
<Directory "/home/the directory_where_your_serverside_pages_is">
Header set Access-Control-Allow-Origin "*"
AllowOverride all
Order allow,deny
Allow from all
</Directory>
In the Header set Access-Control-Allow-Origin "*", you can put a precise URL.
In my case, same code worked fine on Firefox, but not on Google Chrome. Google Chrome's JavaScript console said:
XMLHttpRequest cannot load http://www.xyz.com/getZipInfo.php?zip=11234.
Origin http://xyz.com is not allowed by Access-Control-Allow-Origin.
Refused to get unsafe header "X-JSON"
I had to drop the www part of the Ajax URL for it to match correctly with the origin URL and it worked fine then.
As final note the Mozilla documentation explicitly says that
The above example would fail if the header was wildcarded as:
Access-Control-Allow-Origin: *. Since the Access-Control-Allow-Origin explicitly mentions http://foo.example,
the credential-cognizant content is returned to the invoking web
content.
As consequence is a not simply a bad practice to use '*'. Simply does not work :)
Not all servers support jsonp. It requires the server to set the callback function in it's results. I use this to get json responses from sites that return pure json but don't support jsonp:
function AjaxFeed(){
return $.ajax({
url: 'http://somesite.com/somejsonfile.php',
data: {something: true},
dataType: 'jsonp',
/* Very important */
contentType: 'application/json',
});
}
function GetData() {
AjaxFeed()
/* Everything worked okay. Hooray */
.done(function(data){
return data;
})
/* Okay jQuery is stupid manually fix things */
.fail(function(jqXHR) {
/* Build HTML and update */
var data = jQuery.parseJSON(jqXHR.responseText);
return data;
});
}
I use Apache server, so I've used mod_proxy module. Enable modules:
LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_http_module modules/mod_proxy_http.so
Then add:
ProxyPass /your-proxy-url/ http://service-url:serviceport/
Finally, pass proxy-url to your script.
For PHP - this Work for me on Chrome, safari and firefox
https://w3c.github.io/webappsec-cors-for-developers/#avoid-returning-access-control-allow-origin-null
header('Access-Control-Allow-Origin: null');
using axios call php live services with file://
I also got the same error in Chrome (I didn't test other browers). It was due to the fact that I was navigating on domain.com instead of www.domain.com. A bit strange, but I could solve the problem by adding the following lines to .htaccess. It redirects domain.com to www.domain.com and the problem was solved. I am a lazy web visitor so I almost never type the www but apparently in some cases it is required.
RewriteEngine on
RewriteCond %{HTTP_HOST} ^domain\.com$ [NC]
RewriteRule ^(.*)$ http://www.domain.com/$1 [R=301,L]
Make sure you are using the latest version of JQuery. We were facing this error for JQuery 1.10.2 and the error got resolved after using JQuery 1.11.1
Folks,
I ran into a similar issue. But using Fiddler, I was able to get at the issue. The problem is that the client URL that is configured in the CORS implementation on the Web API side must not have a trailing forward-slash. After submitting your request via Google Chrome and inspect the TextView tab of the Headers section of Fiddler, the error message states something like this:
*"The specified policy origin your_client_url:/' is invalid. It cannot end with a forward slash."
This is real quirky because it worked without any issues on Internet Explorer, but gave me a headache when testing using Google Chrome.
I removed the forward-slash in the CORS code and recompiled the Web API, and now the API is accessible via Chrome and Internet Explorer without any issues. Please give this a shot.
Thanks,
Andy
There is a small problem in the solution posted by CodeGroover above , where if you change a file, you'll have to restart the server to actually use the updated file (at least, in my case).
So searching a bit, I found this one To use:
sudo npm -g install simple-http-server # to install
nserver # to use
And then it will serve at http://localhost:8000.
Suppose we have the xhr 'POST' request that returns 'redirect' status code.
In that case browser is sending additional xhr 'GET' by the given URL.
I am not sure who is doing that call chain: browser itself or js library(using MooTools).
The problem is that the second 'GET' request is not recognized as xhr by the server:
It doesn't have "X-Requested-With" header contains "XMLHttpRequest"
The problem appears only on Firefox, but not on Webkit. So, believe it is not related to js library bug.
Does anyone have ideas how to fix it?
The XHR/browser follows redirects internally.
Apparently firefox is not forwarding non-standard headers?
Sound like you should report a bug to BugZilla