MooTools JSON request - javascript

Trying to get a very simple request working with MooTools Request.JSON. After having no success building it from scratch, I took an example from somewhere and slowly pared it down to the bare, bare minimum, then put it back into my own page. The only things changed are the url and element ID, but to no avail.
Any help, ideas, will be greatly appreciated.
json.php
<?php
$result['name'] = 'yay';
header('Content-type: application/json');
echo json_encode($result);
?>
demo.js (snippet inside window.addEvent('domready', function() { )
$(document.body).getElement('input[id=game_name]').addEvents({
'keydown' : function(){
alert('hmm'); //this fires
var jsonRequest = new Request.JSON({
url: "json.php",
onComplete: function(result){ //changing to onSuccess kills everything afterwards
alert('result.name'); //this fires
alert(result.name); //this does not fire
alert('result.name'); //this does not fire
}
}).get();
}
});
PS. in neither my page, or the pared down example pages, can i get the request to send on domready, only inside an event. why is that?
thanks again
As it turns out, the problem was that I had accidentally loaded a synced duplicate file into my browser that was therefore (obviously) unable to execute anything server side.
Thank you very much for your help.

Several suggestions/questions:
Are you getting any errors in your web browser's console? Which web browser are you using? The fact that the third alert doesn't fire at all suggests that alert(result.name); is throwing an error, in which case, all further execution will be stopped and an error will appear on your browser's console.
When you say "changing to onSuccess kills everything afterwards", what exactly do you mean? Does code further down (i.e. code that's not included in the above code snippet) never execute? Or does onSuccess just never fire?
Is json.php in the same directory as the page where this script is running? Try replacing json.php in url: "json.php" with an absolute URL (/mydirectory/json.php or http://www.mywebsite.com/mydirectory/json.php) and see whether this works.
If it's any help, the following code results in an alert reading "yay" (running on a local server; json.php is a file containing the PHP code in your question):
var jsonRequest = new Request.JSON({
url: "json.php",
onSuccess: function(result) {
alert(result.name);
}
}).get();

you can find a great tutorial here
http://net.tutsplus.com/tutorials/javascript-ajax/checking-username-availability-with-mootools-and-request-json/

Exactly the same problem here.
I solved it by decoding the JSON string, which is given as parameter (instead of the expected object).
onSuccess: function(jsonString) {
console.log(JSON.decode(jsonString));
}
Here ist the documentation:
http://mootools.net/docs/core/Utilities/JSON#JSON:decode

Related

How to debug a jQuery POST AJAX operation?

I want the data coming from the server to show in the <div id="demo"> element.
But sometimes, it just appears and goes, and other times, it is not even showing up. I searched and tried lots of options, but nothing works for me.
My code is:
function loadDoc(){
document.getElementById("demo").innerHTML = "Paragraph changed!";
alert("hello world");
$.ajax({
type:'POST',
url :"new_mark.php",
data :"regno=u4cse13xxx",
success: function(data) {
//$("demo").html = "Narayana!";
document.getElementById("demo").innerHTML = data;
alert(data);
}
});
}
To debug an web site, i advise you tu use the Chrome debugger or on generaly the browser debugger its very simple and usefull.
Click F12 and go to ressources and put an debug point at your line and it finished
Just call the Element and set the the content via a jquery method like text (Reference: .text())
So your code inside success would be:
success: function(data) {
$("#demo").text(data);
}
And maybe you can tell me if it worked? :)
Greets!
Go to the Network tab of the debugger, select your request (new_mark.php), then check the Response tab. If there was an error, it should appear in the response.
For example in Chrome:

Ajax call via POST not working

I have a lil problem with an AJAX request.
We have a lil PHP, JavaScript application (Website). The application is running fine on all desktop browsers + on our old MDE's (some Windows CE6 MDE). Now on our new Motorola MC9200 (Windows Embedded Compact 7 formerly CE7) it's not working anymore.
The problem is some small JavaScript function. It disables the buttons/input fields, starts a Ajax.Request (prototype 1.72 but I tested jQuery 1.11.1 too), does something on the database and when everything went right it is refreshing the site via window.location. This function isn't working always on the new devices. Sometimes it does, sometimes not.
simplified code:
function loadSite(siteName) {
disableForm();
var parameters = {
/* SOME PARAMETERS */
};
new Ajax.Request('ajax/ajax_db_execute.php', {
method: 'post',
parameters: parameters,
onSuccess: callbackFunc
});
}
function callbackFunc(transport) {
response = transport.responseText.evalJSON(true);
if(response.retcode === 0) {
window.location = "start.php?id=<?php echo $id; ?>";
} else {
show_error_box(response.errortext);
enableForm();
}
}
I tried to output the response in the callbackFunc but that function wasn't even called. Next thing I tried was to put some alert at the end of the loadSite function, it was fired everytime. I already checked the parameters and they look fine too.
After that I put some simple fwrite in the php file. It looks like that file isn't even called sometimes. So the question is why?
By changing the method to 'get' I couldn't reproduce the problem and everything is working fine. Problem about that is that I don't want to use get + some parameters might be too long for get to handle.
The parameters in that example were just some simple integers and strings. Does anyone have an idea what might cause the problem and some workaround?
It seems that your post request response is not synchronized. So please use setTimeout function in your post callback like that
setTimeout(function(transport) {
response = transport.responseText.evalJSON(true);
if(response.retcode === 0) {
window.location = "start.php?id=<?php echo $id; ?>";
}
else
{
show_error_box(response.errortext);
enableForm();
}
}, 3000);

jQuery properties - problem

I use this plugin: jQuery.i18n.properties
I put this code:
/* Do stuff when the DOM is ready */
jQuery(document).ready(loadMessage);
/*
* Add elements behaviours.
*/
function loadMessage() {
jQuery("#customMessage").html("test");
jQuery.i18n.properties({
name:'up_mail_messages',
path:'https://static.unifiedpost.com/apps/myup/customer/upmail/upmail_messages/',
mode:'both',
language:'en',
callback: function() {
var messageKey = 'up.mail.test';
//alert(eval(messageKey));
jQuery('#customMessage').html(jQuery.i18n.prop(messageKey));
}
});
}
I do not understand why, in the customeMessage div it prints out:
[up.mail.test]
instead of the value of it:
up.mail.test=messages loaded from en
Can anybody show me where i am wrong? I;ve spent about two hours on it without finding any clue...
Many Thanks.
Ps: here is the message file: https://static.unifiedpost.com/apps/myup/customer/upmail/upmail_messages/up_mail_messages_en.properties
EDIT: After testing locally, all works good. But if the messages files are located to another host (like in the above example) it seems that it fails...It would be nice if anyone can confirm this...
EDIT 1: It does not work because inside the js script there is an ajax call to read the messages files. Well, as you probably know, Cross-Domain XMLHttpRequest Calls are forbidden in ajax due to the browsers restrictions.
Could I trouble you and test a suspicion of mine?
Replace your first line with:
$(document).ready(function() {loadMessage()});
Also, I note that https://static.unifiedpost.com/apps/myup/customer/upmail/upmail_messages/up_mail_messages.properties returns a 404 error, while the en version works well. Is this intentional?
i don't know what is you server return, so in php i just echo something like this :
$arg = 'up.mail.test=messages loaded from en';
exit($arg);
then the js :
.......
callback: function() {
var messageKey = up.mail.test;
//alert(eval(messageKey));
jQuery('#customMessage').html(jQuery.i18n.prop(messageKey));
}
i got this : [messages loaded from en] . is this what you want ?

Problem with jquery ajax in Opera and Google Chrome

I have a page where I need to add a drag and drop functionality to certain elements. When the drop event occurs, it makes an ajax call to a php function and then refreshes the contents of a div. I'm using jQuery with jQueryUI for the drag and drop, and CakePHP as a PHP framework (not sure if this is relevant).
Everything is working just fine in Firefox, Safari and even IE, but in Opera or Chrome the contents of the div isn't refreshed (although the action from the PHP function is executed).
So, here is the code:
jQuery('#lists div').
filter(function() {return this.id.match(/item[\d]+_[\d]+/);}).
each(function() { jQuery(this).draggable( {axis: 'y'}); });
jQuery('#lists div').
filter(function() {
return this.id.match(/list[\d]+/);}).
each(function() {
jQuery(this).droppable({
drop: function(event, ui) {
dropID = jQuery(event.target).attr('id');
dragID = jQuery(ui.draggable).attr('id');
itemID = dragID.substr(dragID.lastIndexOf('_') + 1);
oldListID = dragID.substr(4).replace(/_[\d]+/g, '');
newListID = drop.substr(4);
jQuery.ajax({
url: "/lists/itemToList/"+itemID+"/"+oldListID+
"/"+newListID,
type: "POST",
success: function (data) {
jQuery('#lists').html(data);}
});
}
});
});
Basically, the success function isn't executed, but if I try to see the errorThrown (on the error event) it is "undefined"
Try something like this:
jQuery.ajax({
url: "/lists/itemToList/"+itemID+"/"+oldListID+
"/"+newListID,
type: "POST",
success: function (data) {
jQuery('#lists').html(data);
}
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(XMLHttpRequest.status);
alert(XMLHttpRequest.responseText);
}
});
It will show you what http response are you getting for your request. I had the same problem some time ago. My script worked great in Firefox and Chrome, but it didn't do anything in Opera and IE. I checked it and the problem was, that the php backend was returning 404 (I still don't know how did it work under Chrome and FF).
I know it's been a long time since I've posted the question, but here is what I found to be the solution, in case somebody else needs it: the problem was not the in javascript but with CakePHP: the html that was added on success contained an ajax form (rendered using $ajax->form()). $ajax->form() needed the $data variable from the controller to be an array, but for some reason it wasn't, and this broke the rendering of the form, and Opera and Chrome didn't like this. So the solution was to simply add
$this->data = array();
to the itemToList() function in my controller.
I don't see anything in the code that would cause a cross browser issue. My feeling is that it's a problem doesn't lie in the code at all, but in the rendering of the div and/or its contents in Chrome and Opera (i.e. a CSS problem or something along those lines where the innerHTML of the div is updated, but because of styling or positioning you don't get the visual result you were looking for).
Have you checked using Dragonfly or some other developer tool to verify that the contents of the target element are in fact unchanged after a successful request? Along those lines have you tried stepping through the code execution in the problem browsers? You could also try adding a error handler to the JQuery.ajax options to see if there is some problem with the request itself, although I don't believe that is where the problem lies.
EDIT: I didn't see that last bit below the code block. So you have verified that the success handler isn't being executed. You said that you did try and implement an error handler for the request and got some undefined result, but I don't see it in the code. Could you post the code for the error handler and describe what in the error is undefined?
I think he means, that alert(errorThrown) is showing 'undefined'.

jQuery .getJSON Firefox 3 Syntax Error Undefined

I'm getting a syntax error (undefined line 1 test.js) in Firefox 3 when I run this code. The alert works properly (it displays 'work') but I have no idea why I am receiving the syntax error.
jQuery code:
$.getJSON("json/test.js", function(data) {
alert(data[0].test);
});
test.js:
[{"test": "work"}]
Any ideas? I'm working on this for a larger .js file but I've narrowed it down to this code. What's crazy is if I replace the local file with a remote path there is no syntax error (here's an example):
http://api.flickr.com/services/feeds/photos_public.gne?tags=cat&tagmode=any&format=json&jsoncallback=?
I found a solution to kick that error
$.ajaxSetup({'beforeSend': function(xhr){
if (xhr.overrideMimeType)
xhr.overrideMimeType("text/plain");
}
});
Now the explanation:
In firefox 3 (and I asume only firefox THREE) every file that has the mime-type of "text/xml" is parsed and syntax-checked. If you start your JSON with an "[" it will raise an Syntax Error, if it starts with "{" it's an "Malformed Error" (my translation for "nicht wohlgeformt").
If I access my json-file from an local script - no server is included in this progress - I have to override the mime-type... Maybe you set your MIME-Type for that very file wrong...
How ever, adding this little piece of code will save you from an error-message
Edit: In jquery 1.5.1 or higher, you can use the mimeType option to achieve the same effect. To set it as a default for all requests, use
$.ajaxSetup({ mimeType: "text/plain" });
You can also use it with $.ajax directly, i.e., your calls translates to
$.ajax({
url: "json/test.js",
dataType: "json",
mimeType: "textPlain",
success: function(data){
alert(data[0].test);
} });
getJSON may be insisting on at least one name:value pair.
A straight array ["item0","item1","Item2"] is valid JSON, but there's nothing to reference it with in the callback function for getJSON.
In this little array of Zip codes:
{"result":[["43001","ALEXANDRIA"],["43002","AMLIN"],["43003","ASHLEY"],["43004","BLACKLICK"],["43005","BLADENSBURG"],["43006","BRINKHAVEN"]]}
... I was stuck until I added the {"result": tag. Afterward I could reference it:
<script>
$.getJSON("temp_test_json.php","",
function(data) {
$.each(data.result, function(i, item) {
alert(item[0]+ " " + i);
if (i > 4 ) return false;
});
});
</script>
... I also found it was just easier to use $.each().
This may sound really really dumb, but change the file extension for test.js from .js to .txt. I had the same thing happen with perfectly valid JSON data files with pretty well any extension except .txt (example: .json, .i18n). Since I've changed the extension, I get the data and use it just fine.
Like I said, it may sound dumb but it worked for me.
HI
I have this same error when testing the web page on my local PC, but once it is up on the hosting server the error no longer happens. Sorry - I have no idea of the reason, but thought it may help someone else track down the reason
Try renaming "test.js" to "test.json", which is what Wikipedia says is the official extension for JSON files. Maybe it's being processed as Javascript at some point.
Have you tried disabling all the Firefox extensions?
I usually get some errors in the Firebug console that are caused by the extensions, not by the webs being visited.
Check if there's ; at the end of the test.js. jQuery executes eval("(" + data + ")") and semicolon would prevent Firefox from finding closing parenthesis. And there might be some other unseen characters that prevents it from doing so.
I can tell you why this remote location working though, it's because it's executed in completely different manner. Since it has jsoncallback=? as the part of query parameters, jQuery thinks of it as of JSONP and actually inserts it into the DOM inside <script> tags. Try use "json/test.js?callback=?" as target, it might help too.
What kind of webserver are you running that on? I once had an issue reading a JSON file on IIS because it wasn't defined as a valid MIME type.
Try configuring the content type of the .js file. Firefox expects it to be text/plain, apparently. You can do that as Peter Hoffmann does above, or you can set the content type header server side.
This might mean a server-side configuration change (like apache's mime.types file), or if the json is served from a script, setting the content-type header in the script.
Or at least that seems to have made the error go away for me.
I had a similar problem but was looping through a for loop. I think the problem might be that the index is out of bound.
Kien
For the people who don't use jQuery, you need to call the overrideMimeType method before sending the request:
var r = new XMLHttpRequest();
r.open("GET", filepath, true);
r.overrideMimeType("text/plain");

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