Develop Reference

Wikipedia API. File not found Error

I'm trying to make a wikipedia search bar. The idea is to send a new AJAX request every time search input is changed. I'm using https://www.mediawiki.org/wiki/API:Search_and_discovery as a guideline.
var search = $('#search');
search.keyup(function() {
if (search.val() === '') {
result.html('');
}
$.ajax({
url: '//en.wikipedia.org/w/api.php',
data: {
action: 'query',
list: 'search',
format: 'json',
srsearch: search.val()
},
dataType: 'jsonp',
success: function(response) {
console.log("success!");
}
});
});
However, success function is not even triggered.
On any keypress the error I get is this ("d" pressed):
jquery-2.1.1.min.js:4 GET file://en.wikipedia.org/w/api.php?>callback=jQuery21107844703783826772_1484403407494&action=query&list=search&srse>arch=d&format=json&_=1484403407495 net::ERR_FILE_NOT_FOUND
Thank you in advance for any help or guidance!

Well, you're probably trying to do a AJAX request without a local server (opening your file directly in the browser).
First of all, your url options starts with //en... (without the protocol). It indicates that it'll construct your full url using the same protocol you're using. In this case: file://. That's because your browser is trying to reach file://en.wikipedia.org/....
So, you can set your url to https://en.wikipedia.org/w/api.php to make it work.
Just replace:
url: '//en.wikipedia.org/w/api.php',
with:
url: 'https://en.wikipedia.org/w/api.php',

Looks like you're running it from a simple html file located in your filesystem, in other words not running it from a web server (even local).
Try calling the api with
url: 'https://en.wikipedia.org/w/api.php'
or run the file from a web server (can be a local one).

Strange $.post() AJAX error when parsing JSON

I am facing this strange error in using $.post.
works
$("#add-video").click(function(){
var url = $("#new-video-url").val();
$('#loader').show();
$.post( base_url + "forms/coach/get_url.php", { url:url, base_url:base_url }, function(data){
alert(data);
$('#loader').hide();
});
});
The above piece of code, shows me the json array I am receiving using a php file, and also shows the title field here, and hides the loader image.
But when I alert(data.title), it shows me undefined. More over, when I add datatype 'json' to $.post,
doesn't work
$("#add-video").click(function(){
var url = $("#new-video-url").val();
$('#loader').show();
$.post( base_url + "forms/coach/get_url.php", { url:url, base_url:base_url }, function(data){
alert(data);
$('#loader').hide();
}, "json"); //Added datatype here.
});
This neither alerts anything nor does it hide the loader image. I also tried,
$("#add-video").click(function(){
var url = $("#new-video-url").val();
$('#loader').show();
$.post( base_url + "forms/coach/get_url.php", { url:url, base_url:base_url }, function(data){
jQuery.parseJSON(data);
alert(data.title);
$('#loader').hide();
});
});
The above one too neither alerts anything nor does it hide the loader. And then I tried this one too that did nothing.
$("#add-video").click(function(){
var url = $("#new-video-url").val();
$('#loader').show();
$.post( base_url + "forms/coach/get_url.php", { url:url, base_url:base_url }, function(data){
jQuery.parseJSON(data); //tried without this too.
alert(data['title']);
$('#loader').hide();
});
});
The strangest thing is that I have previously used json as I have shown in the 2nd script(out of 4), and that works normally. My JS console too doesn't show any errors or warning. What am I doing wrong here? How do I access the title field of data?
If this helps, here is how I send the json array,
$json = array("title" => $title, "embed" => $embed, "desc" => $desc, "duration" => $duration, "date" => $date);
print_r(json_encode($json));
I would really appreciate if someone can point out the error and tell me why my scripts are failing, similar functions worked in other js file.
here is my data, that is returned by server,
{"title":"Sunn Raha Hai Na Tu Aashiqui 2 Full Song With Lyrics |
Aditya Roy Kapur, Shraddha Kapoor","embed":"\r\t\t\t\t\t\r\t\t\t\t\t</param></param>\r\t\t\t\t\t</param>\r\t\t\t\t\t\r\t\t\t\t\t</embed></object>","desc":"Presenting
full song \"Sun Raha Hai Na Tu\" with lyrics from movie \"Aashiqui 2\"
produced by T-Series Films & Vishesh Films, starring Aditya Roy Kapur,
Shraddha Kapoor in voice of Ankit Tiwari. \n\nSong: SUNN RAHA
HAI\nSinger: ANKIT TIWARI\nMusic Director: ANKIT TIWARI\nAssistant Mix
Engineer - MICHAEL EDWIN PILLAI\nMixed and Mastered by ERIC PILLAI
(FUTURE SOUND OF BOMBAY)\nLyrics:SANDEEP NATH\nMovie: AASHIQUI
2\nProducer: BHUSHAN KUMAR KRISHAN KUAMR Producer: MUKESH BHATT
\nDirector: MOHIT SURI\nMusic Label: T-SERIES\n\nBuy from iTunes -
https://itunes.apple.com/in/album/aashiqui-2-original-motion/id630590910?ls=1\n\nEnjoy
& stay connected with us!! \n\nSUBSCRIBE T-Series channel for
unlimited entertainment\nhttp://www.youtube.com/tseries\n\nCircle
us on G+ \nhttp://www.google.com/+tseriesmusic\n\nLike us on
Facebook\nhttp://www.facebook.com/tseriesmusic\n\nFollow
us\nhttp://www.twitter.com/_Tseries","duration":"391","date":"2013-04-03"}
Edit
This worked suddenly.. :o
$("#add-video").click(function(){
var url = $("#new-video-url").val();
$('#loader').show();
$.post( base_url + "forms/coach/get_url.php", { url:url, base_url:base_url }, function(data){
alert(data.desc);
console.log(data.desc);
$("#loader").hide();
}, "json");
});

In comments, you mention that this AJAX corresponds to a YouTube API.
YouTube's blog announced in 2012 that they would support CORS, which uses server-side header flags that compatible browsers interpret as permitting requests that would otherwise be prohibited by browser security Same-Origin-Policy.
Assuming, as you say, the first example worked, the first issue was "Why did (a subsequent) alert(data.title) fail? (my edit) ". If you type alert(data.title) in the console, it will fail because the scope of data is the callback function where it is defined as a parameter, and in the global scope data is undefined. If you try to pass data back to the global scope somehow, it can still be undefined because $.post returns immediately, before the data has been fetched, and merely queues a request and sets the callback function you supply to handle the reply.
The second example, which explicitly sets the $.post dataType parameter to 'json', may fail with CORS based API because the mime types for json are not allowed to be sent up to the server as Content-Type: for a simple CORS request, and $.post will as far as I know only do simple requests without preflight. $.ajax can possibly do the more complex requests if correctly applied.
The work around to keep using $.post is not to use json as the expected data type, send requests up as form data, the server may send you back json anyway if that is what the API says will happen, which can be verified while testing the code.
From https://developer.mozilla.org/en-US/docs/HTTP/Access_control_CORS
Simple requests
A simple cross-site request is one that:
Only uses GET, HEAD or POST.
If POST is used to send data to the
server, the Content-Type of the data sent to the server with the HTTP
POST request is one of application/x-www-form-urlencoded,
multipart/form-data, or text/plain.
Notice that application/json did not make the list of what Content-Type is permissible in a simple CORS request.
See also A CORS POST request works from plain javascript, but why not with jQuery?

Use ajax as
$.ajax({
url:url,
type:'post',
dataType:'json',
success:callback
})
With this type you can set lots of parameter in low level.
With datatype attribute jQuery parses JSON and send data as callback function.

I think you have to replace all single \ with double '\' to feed it to JSON.parse.

How I get respone text in application and bind to the label in cross ajax call

I am calling the web service from other domain using Ajax call and I want to get returned response from server in my application by using following code I get response text in firebug but not in my JavaScript code. Control are not showing success and error response it goes out directly.
I want response in my success or error section but both not handling in this.
I am trying lot but not finding any solution please any one help me.
I am in a trouble. I hope somebody can help me for calling cross domain web service by using Ajax call. I am trying from 1 week but didn't find any solution till. I am getting response on browser but not getting it on my actual code.
My JavaScript code.
crossdomain.async_load_javascript(jquery_path, function () {
$(function () {
crossdomain.ajax({
type: "GET",
url: "http://192.168.15.188/Service/Service.svc/GetMachineInfo?serialNumber="+123,
success: function (txt) {
$('#responseget').html(txt);
alert("hii get");
}
});
crossdomain.ajax({
type: "POST",
url: "http://192.168.15.188/Server/Service.svc/GetEvents/",
// data: "origin=" + escape(origin),
success: function (txt) {
$('#responsepost').html(txt);
alert("hii post");
}
});
});
});
</script>

You can't simply ignore the Same Origin Policy.
There are only three solutions to fetch an answer from a web-service coming from another domain :
do it server-side (on your server)
let the browser think it comes from the same domain by using a proxy on your server
change the web service server, by making it JSONP or (much cleaner today) by adding CORS headers

Call similar to $.get in $.ajax

I have the following code:
$.get(url, {}, checkResponse)
And the following function:
function checkResponse(content) {}
The parameter "content" here is the result of the "get". I wanted to implement $.ajax to able to wait for the process to complete before it jump to the next chunk of code. I tried the following code but it didn't work.
$.ajax({
async: false,
type: 'GET',
url: url,
success: function (data) {
alert(data.toString());
checkResponse(data);
},
error: function (data) {
alert("error");
}
});
Here's what happened, the alert for the data.toString() gives empty string value while it should give me the url page content, and after it hits the alert it jumps to the error section and displays the alert "error".

According to the discussion in the comments section you are trying to send cross domain AJAX calls to arbitrary urls on the internet. Due to the same origin policy restriction that's built into the browsers this is not possible.
Possible workarounds involve using JSONP or CORS but since you will be sending requests to arbitrary urls that you have no control over they might not be an option. The only viable solution in this case is for you to write a server side script that you will host on your domain acting as a bridge. This script will receive an url as parameter and send an HTTP request to this url in order to retrieve the result. Then it will simply return the result back to the response. Finally you will send an AJAX request to your own server side script.

AD FS 2.0 Authentication and AJAX

I have a web site that is trying to call an MVC controller action on another web site. These sites are both setup as relying party trusts in AD FS 2.0. Everything authenticates and works fine when opening pages in the browser window between the two sites. However, when trying to call a controller action from JavaScript using the jQuery AJAX method it always fails. Here is a code snippet of what I'm trying to do...
$.ajax({
url: "relyingPartySite/Controller/Action",
data: { foobar },
dataType: "json",
type: "POST",
async: false,
cache: false,
success: function (data) {
// do something here
},
error: function (data, status) {
alert(status);
}
});
The issue is that AD FS uses JavaScript to post a hidden html form to the relying party.
When tracing with Fiddler I can see it get to the AD FS site and return this html form which should post and redirect to the controller action authenticated. The problem is this form is coming back as the result of the ajax request and obviously going to fail with a parser error since the ajax request expects json from the controller action. It seems like this would be a common scenario, so what is the proper way to communicate with AD FS from AJAX and handle this redirection?

You have two options.
More info here.
The first is to share a session cookie between an entry application (one that is HTML based) and your API solutions. You configure both applications to use the same WIF cookie. This only works if both applications are on the same root domain.
See the above post or this stackoverflow question.
The other option is to disable the passiveRedirect for AJAX requests (as Gutek's answer). This will return a http status code of 401 which you can handle in Javascript.
When you detect the 401, you load a dummy page (or a "Authenticating" dialog which could double as a login dialog if credentials need to be given again) in an iFrame. When the iFrame has completed you then attempt the call again. This time the session cookie will be present on the call and it should succeed.
//Requires Jquery 1.9+
var webAPIHtmlPage = "http://webapi.somedomain/preauth.html"
function authenticate() {
return $.Deferred(function (d) {
//Potentially could make this into a little popup layer
//that shows we are authenticating, and allows for re-authentication if needed
var iFrame = $("<iframe></iframe>");
iFrame.hide();
iFrame.appendTo("body");
iFrame.attr('src', webAPIHtmlPage);
iFrame.load(function () {
iFrame.remove();
d.resolve();
});
});
};
function makeCall() {
return $.getJSON(uri)
.then(function(data) {
return $.Deferred(function(d) { d.resolve(data); });
},
function(error) {
if (error.status == 401) {
//Authenticating,
//TODO:should add a check to prevnet infinite loop
return authenticate().then(function() {
//Making the call again
return makeCall();
});
} else {
return $.Deferred(function(d) {
d.reject(error);
});
}
});
}

If you do not want to receive HTML with the link you can handle AuthorizationFailed on WSFederationAuthenticationModule and set RedirectToIdentityProvider to false on Ajax calls only.
for example:
FederatedAuthentication.WSFederationAuthenticationModule.AuthorizationFailed += (sender, e) =>
{
if (Context.Request.RequestContext.HttpContext.Request.IsAjaxRequest())
{
e.RedirectToIdentityProvider = false;
}
};
This with Authorize attribute will return you status code 401 and if you want to have something different, then you can implement own Authorize attribute and write special code on Ajax Request.

In the project which I currently work with, we had the same issue with SAML token expiration on the clientside and causing issues with ajax calls. In our particular case we needed all requests to be enqueud after the first 401 is encountered and after successful authentication all of them could be resent. The authentication uses the iframe solution suggested by Adam Mills, but also goes a little further in case user credentials need to be entered, which is done by displaying a dialog informing the user to login on an external view (since ADFS does not allow displaying login page in an iframe atleast not default configuration) during which waiting request are waiting to be finished but the user needs to login on from an external page. The waiting requests can also be rejected if user chooses to Cancel and in those cases jquery error will be called for each request.
Here's a link to a gist with the example code:
https://gist.github.com/kavhad/bb0d8e4a446496a6c05a
Note my code is based on usage of jquery for handling all ajax request. If your ajax request are being handled by vanilla javascript, other libraries or frameworks then you can perhaps find some inspiration in this example. The usage of jquery ui is only because of the dialog and stands for a small portion of the code which could easly be swapped out.
Update
Sorry I changed my github account name and that's why link did not work. It should work now.

First of all you say you are trying to make an ajax call to another website, does your call conforms to same origin policy of web browsers? If it does then you are expecting html as a response from your server, changedatatype of the ajax call to dataType: "html", then insert the form into your DOM.

Perhaps the 2 first posts of this serie will help you. They consider ADFS and AJAX requests
What I think I would try to do is to see why the authentication cookies are not transmitted through ajax, and find a mean to send them with my request. Or wrap the ajax call in a function that pre authenticate by retrieving the html form, appending it hidden to the DOM, submitting it (it will hopefully set the good cookies) then send the appropriate request you wanted to send originally

You can do only this type of datatype
"xml": Treat the response as an XML document that can be processed via jQuery.
"html": Treat the response as HTML (plain text); included script tags are evaluated.
"script": Evaluates the response as JavaScript and evaluates it.
"json": Evaluates the response as JSON and sends a JavaScript Object to the success callback.
If you can see in your fiddler that is returning only html then change your data type to html or if that only a script code then you can use script.

You should create a file anyname like json.php and then put the connection to the relayparty website this should works
$.ajax({
url: "json.php",
data: { foobar },
dataType: "json",
type: "POST",
async: false,
cache: false,
success: function (data) {
// do something here
},
error: function (data, status) {
alert(status);
}
});