Develop Reference

Ajax: How to send FormData inside of json object

To give you a better understanding consider my ajax request:
$.ajax({
url: '{% url "validate-upload-single" %}',
type: "POST",
data: JSON.stringify({
'mainForm': Myform,
'currentForm': 1,
}),
dataType: 'json', // response type
Where:
var Myform = new FormData( $(this)[0] );
The problem is that when i send the request, i get back an empty 'dict' on the server side. Im using Django as my backend
DJANGO VIEW:
print('SORTING THE POST REQUEST')
body = request.body.decode('utf-8')
serialized = loads(body)
print(f'POST: {request.POST}')
print(f'Body: {body}')
print(f'Serialized: {serialized}')
RESULT:
SORTING THE POST REQUEST
POST: <QueryDict: {'{"mainForm":{},"currentForm":1}': ['']}>
Body: {"mainForm":{},"currentForm":1}
Serialized: {'mainForm': {}, 'currentForm': 1}
I've tried $("form").serializeArray() but this only return text data, files seem to be missing

I guess the problem is with contentType header - it should be 'multipart/form-data'. Check this link to make it work with jQuery.ajax

In the .js file you HAVE TO add the fist block of csrf token for properly working.
//Getting csrf token
var csrftoken = jQuery("[name=csrfmiddlewaretoken]").val();
function csrfSafeMethod(method) {
// these HTTP methods do not require CSRF protection
return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method));
}
$.ajaxSetup({
beforeSend: function(xhr, settings) {
if (!csrfSafeMethod(settings.type) && !this.crossDomain) {
xhr.setRequestHeader("X-CSRFToken", csrftoken);
}
}
});
Then you use json in you ajax, getting the template that you want to display by variable here "html_form":
// Submit post on submit
$('#post-form').on('submit', function(event){
event.preventDefault();
console.log("form submitted!") // sanity check
//Send data to server for getting back sorted
$.ajax({
url: '/schedule/sort_group/',
async: true,
type: 'post',
data: { //data sent with the post request
group_field_value: $("#select_group").children("#group-option:selected").val(),
lector_field_value: $("#select_lector").children("#lector-option:selected").attr("name"),
},
dataType: 'json',
success: function (data) {
$("#change_by_select").html(data.html_form);
}
});
});
In the views.py file at the bottom you need to determine the data like that:
data['html_form'] = render_to_string('schedule/select_sort.html', context,
request=request)
return JsonResponse(data)
So I suggest the information that you want to retrieve from the server put into the particular another file, whatever it would be (dictionary or lists or other data structures or html templates).
I hope it would help. Feel free to ask any questions.

How to return data from PHP to a ajax function

Hi I am currently learning php and I am trying to get data from php file using the below script but i am not getting any response
$.ajax({
type: 'POST',
url: "mark_mod.php",
data: data_set,
dataType: "JSON",
success: function(data) {
alert("Response : " ); // not triggering
}
});
my php return stmt

There might be problems with File URL or file access. You can use complete callback to check request for errors like that:
$.ajax({
type: 'POST',
url: "mark_mod.php",
data: data_set,
dataType: "JSON",
success: function(data) {
alert("Response : " );
},
// This method will be fired when request completes
complete: function(xxhr, status) {
alert("Status code: " + status);
}
});
If the status code is not success that means there is something wrong with your request.
You can check more callback options here.
It doesn't matter whether you use return or echo in your PHP file.
The success method must get a call if it's fine. However, if you use
return instead of echo, nothing will append to your request's data.

On the other hand, The PHP response will include in your 'data' variable in the function success.
You need use data in the assync function success
success: function(data) {
alert("Response : " + data);
},

Thanks for your Responses. I got the Solution to my problem. It seems since Ajax is asynchronous... its taking time to receive the resultant echo value from my php file. so I had to synchronize my Jquery using async : False.

$(function(){
$('#formID').on('submit',function(){
const data_set={
name:"Nipu chakraborty",
"phone":"01783837xxx"
}
$.ajax({
type: 'POST',
url: "mark_mod.php",
data: data_set,
dataType: "JSON",
success: function(data) {
alert(data);
}
});
});
});

Ajax POST error (400 BAD REQUEST)

and thank you in advance for helping me.
I'm trying to make a POST where I pass the TOKEN in the URL and I want to pass another param too so I can save the info in the DB. I have this:
$("#btnAddCompany").click(function(e) {
var token = "123";
var companyValue = document.getElementById("companyValue").value;
var obj ={CompanyId: 4 ,Name: companyValue }
var postData = JSON.stringify(obj);
console.log(postData);
$.ajax({
type: "POST", //REQUEST TYPE
dataType: "json", //RESPONSE TYPE
contentType: "application/json",
data: postData,
url: "http://banametric.ddns.net/BanaMetricWebServices/BanaSov_WS.svc/CompanySave/"+token,
success: function(data) {
toastr.success("Lidl Adicionado!");
},
error: function(err) {
console.log("AJAX error in request: " + JSON.stringify(err, null, 2));
}
}).always(function(jqXHR, textStatus) {
if (textStatus != "success") {
alert("Error: " + jqXHR.statusText);
}
})
});
But I'm getting an 400 error (Bad Request) so I assume that I'm making something wrong, but I don't find out what. The error trace is this:
AJAX error in request: { "readyState": 4, "responseText": "\r\n
The server encountered an error processing the request. The
exception message is 'The incoming message has an unexpected message
format 'Raw'. The expected message formats for the operation are
'Xml', 'Json'. This can be because a WebContentTypeMapper has not been
configured on the binding. See server logs for more
details. The exception stack trace is: \r\n at
System.ServiceModel.Dispatcher.DemultiplexingDispatchMessageFormatter.DeserializeRequest(Message
message, Object[] parameters)\r\n at

It's error because of
The expected message formats for the operation are 'Xml', 'Json'.
So you can pass contentType in your ajax call
$.ajax({
....,
contentType: "application/json"
})

I am not sure, but it depends on what server wants to read from you.
Server does not want to read raw bytes, it wants xml or json
Try to add headers like
beforeSend: function(xhrObj){
xhrObj.setRequestHeader("Content-Type","application/json");
xhrObj.setRequestHeader("Accept","application/json");
},
in $.ajax() function

You need to set the content type header in your request to inform the server you're sending the data as JSON.
The error message is telling you that the server does not understand the content you're sending it - you have to give it a hint that the data is in a particular format, especially because, again as mentioned in the error message, it allows you to submit in more than one different format (JSON or XML in this case).
Adding
contentType: "application/json"
to the options in your $.ajax call should resolve the issue.
P.S. We can't see the signature of your controller method but it's possible you may also need to give your parameter a name within the JSON, e.g. something like data: JSON.stringify({ "companyValue": postData }); , but there's not enough info in your question to say for certain what the correct structure should be.

$("body").on("submit", ".example_form", function() {
$.ajax({
url: 'http://example.com/{ROUTE_URL}',
data: new FormData(this),
processData: false,
contentType: false,
/* OR contentType: "application/json; charset=utf-8"*/
type: 'POST',
dataType: "json",
success: function(data) {
console.log(data);
}
});
});

Instead of this
var postData = JSON.stringify(companyValue);
why don't you try this:
var obj ={token :token ,companyValue:companyValue }
And then make use of the json stringify function
var postData = JSON.stringify(obj);
After that in ajax call only change the url:
url: "http://webservice/CompanySave/"

How to add local json file in jsfiddle?

How can I add a JSON file in jsfiddle? I have a JSON file but I am not able to attach it in jsfiddle. I can make a JSON object and use it, but is there any way to add an external JSON file to a fiddle?

Myjson.com provides api, which runs in Jsfiddle.net.
Custom my myjson:
// Loading JSON with CROS
var url = 'https://api.myjson.com/bins/3ko1q';
$.ajax({
type: 'GET',
url: url,
async: false,
contentType: "application/json",
dataType: 'json',
success: function (data) {
alert('success');
console.log(data);
},
error: function (e) {
alert('error');
console.log(e);
}
});
Myjson GET Example:
// 1. Create valid uri via POST
// 2. GET using newly created uri
var obj = {
"key": "value",
"key2": "value2"
};
var data = JSON.stringify(obj);
$("#clickMe").click(function () {
$.ajax({
url: "https://api.myjson.com/bins",
type: "POST",
data: data,
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (data, textStatus, jqXHR) {
// load created json
$.get(data.uri, function (data, textStatus, jqXHR) {
var json = JSON.stringify(data);
$("#data").val(json);
});
}
});
});

You can harness the power of Cross-Origin Resource Sharing (CORS) to achieve your task.
Basically how CORS works is that if the Access-Control-Allow-Orign header is set in the HTTP response, then the content loaded by AJAX can be used in our script regardless of the fact it is on the same domain or some other.
Now for your purpose, you can upload your local JSON file to Dropbox's Public folder and get a Public URL, that you can load by a simple AJAX call.
The AJAX call will succeed in this case because Dropbox sets the following value in the response Access-Control-Allow-Orign:* which means any domain can use the loaded content.
Jquery code will be something like this(you can even use pure JavaScript if you prefer ).
var url = 'https://dl.dropboxusercontent.com/u/94145612/example.json';
var myJsonData= {};
$.ajax({
type: 'GET',
url: url,
async: false,
contentType: "application/json",
dataType: 'json',
success: function (data) {
alert('success');
console.log(data);
myJsonData= data;
},
error: function (e) {
alert('error');
console.log(e);
}
});
Example JSFiddle

Based on your comment, you want to use a pure JSON file as an external resource in a jsFiddle. You can't do this, because pure JSON is not JavaScript. Say you try to include http://example.com/foo.json as an external resource, and that file contains the following:
{"foo":"bar"}
This will result in Uncaught SyntaxError: Unexpected token :, because the JSON object is not valid JavaScript by itself.
But if you assign the JSON object to a variable, like so:
var foo = {"foo":"bar"};
then no problem.
Solution: use a modified version of your file to initialize a variable for use in the jsFiddle.

Accessing ajax POST response in javascript

I'm making ajax POST request from javascript function:
function UpdateMetrics() {
$.ajax({
type: "POST",
url: "MyHandler.ashx?Param1=value1",
data: "{}",
contentType: "text/json; charset=utf-8",
dataType: "text",
success: function (msg) {
var jsonUpdatedData = msg;
...
}
});
}
From my handler, I'm sending json string with:
context.Response.write(json);
I think I'll get it in msg.
I also want to send other string (count). So I'm trying to use header info along with json data. So I added this line:
context.Response.Headers.Add("MaxCount",Convert.ToString(tempList.Count));
If this is right way to do it, how can I access it in my success function?

To access headers in your success function, add in 2 more arguments to your function, the status code and the jqXHR object, which you can read the documentation for at api.jquery.com.
So, your function should look like:
success: function (msg, status, jqXHR) {
var jsonUpdatedData = msg;
...
}
However, as pointed out in comments, it's probably best not to use the header to send data. You should probably just include it in the json you send out.
You also need to tell jQuery to interpret the response as json by setting
dataType: "json"
Otherwise, it will just be returned to you as text.

Your requirement to get the header data in ajax post success can be achieved using getResponseHeader method please refer the below code snippet.
function UpdateMetrics() {
var callback = $.ajax({
type: "POST",
url: "MyHandler.ashx?Param1=value1",
data: "{}",
contentType: "text/json; charset=utf-8",
dataType: "text",
success: function (msg) {
var jsonUpdatedData = msg;
var headerdata = callback.getResponseHeader("MaxCount");
// Where MaxCount is name provided in the header.
...
}
});
}
Thanks