$.extend ignoring 'traditional' flag - ajax

I'm working in an ASP.NET MVC4 application, and as such, all array data sent to the server over ajax must be sent using the traditional option. (no [] for POST variables).
The problem is, I also have a filter set-up which requires an AntiforgeryToken to be sent with each ajax POST.
I have fixed this using an ajaxPrefilter like this:
$.ajaxPrefilter(function (options, originalOptions) {
if (options.type.toUpperCase() == "POST") {
options.data = $.param($.extend(originalOptions.data, { __RequestVerificationToken: "antiForgeryToken" }));
}
});
This works great, and adds the __RequestVerificationToken to all POSTs.
However, it also causes my data not to be parametrized according to the traditional flag.
Does anybody know how I can modify my prefilter to account for this?
Example can be found here:
http://jsbin.com/IxoKIKA/2/edit

You forgot to pass the traditional argument to $.param(). You should write:
options.data = $.param($.extend(originalOptions.data, {
__RequestVerificationToken: "antiForgeryToken"
}), true);

Related

ASP.NET Core API POST parameter is always null from Firefox

In my Angular2 Application, I'm submitting a form and send data through POST API to dotnet core backend. I've created a new form, that is working fine with chrome, but on firefox, I'm receiving null in POST API parameter.
I'm all stuck what to search and how to?? I've checked every possible issue and didn't find anything, because App is working fine with chrome, all data is up to date and correct but a single form is not working on firefox.
Can anyone help me out what to do? because I'm totally stuck and have
no idea what to do??
My Endpoints are;
[HttpPost]
[Route("api/Intimation/SaveIntimation")]
public async Task<ActionResult> SaveIntimation([FromBody] ViewModelCreateIntimation objCreateIntimation)
{
if (objCreateIntimation == null || objCreateIntimation.objIntimation == null)
{
return Ok("null received");
}
// remaining code
}
my service on angular side
saveIntimation(intiModel) {
console.log(intiModel);
return this.httpClient.post<ViewModelResponse>(this.baseUrl + this._SubmitIntimationUrl, JSON.stringify(intiModel), { headers: this.configurations.getHeaderWithAuth() });
}
where this._SubmitIntimationUrl is "/api/Intimation/SaveIntimation", intiModel is object that I'm passing.
Controller function - Angular
this.intimationModel = this.admissionForm.value;
this.adminService.SubmitAdmissionIntimationService(this.createIntimationModel).subscribe(
(response) => {
this.responseModel = response;
// further process
},
(error) => {
this.notification.onClear();
this.notification.onError(this.errorHandler.handleError(error).error, Constants.MESSAGE_ERROR);
}
);
Data that is sending from service (Last place where I can check data)
The problem looks like it's because of the name of the parameter in your controller is different to that being passed up in the request.
In your controller, the parameter the framework is trying to bind to is called objCreateIntimation, but your request shows you're sending up objIntimation instead. As they have different names, the model binder has no idea that objIntimation should be bound to objCreateIntimation.
Give them both the same name, and that should fix it for you.
I went through same issue once, and It took almost a day to figure out the reason behind it,
do check your date pickers and its values, and make sure it is not null and its format is also correct. Because firefox is a bit strict in this matter and a litter change in datepicker makes it null.
hope it helps you.

How to prevent server call for empty string in Select2 with remote data?

I noticed that the Select2 widget serving options with remote data was making a call even when I enter just empty spaces. This usually returns me an empty array, but I would like to eliminate this call altogether.
So here is what I did.
The Select2 plugin allows us to define our own AJAX call handler via the transport option.
From the docs :
Select2 uses the transport method defined in ajax.transport to send requests to your API. By default, this transport method is jQuery.ajax but this can be changed
So here is how you can eliminate the unnecessary call altogether.
$('select').select2({
...
ajax: {
transport: function (params, success, failure) {
if (!params.data.q.trim().length) {
return false;
}
var $request = $.ajax(params);
$request.then(success);
$request.fail(failure);
return $request;
}
}
...
})
A more detailed snippet at my blog.
Select2 has a minimumInputLength option which will handle this for you. It will display a notice when the user needs to enter more characters, and then send the request out when enough have been entered.

MVC: How to serialize a knockout object into a JSON property through AJAX

I'm trying to serialize a knockout object and pass it into a JSON property called multipleCharge.
This is the ajax code to send data though Get method to a mvc controller
$.ajax({
url: _url,
type: 'GET',
//data: { multipleCharge: ko.mapping.toJS(_vm)},
data: { multipleCharge : { AccountId : 2 } },
dataType: 'json'});
And this is the method
[HttpGet]
public HttpResponseMessage GetSalesInvoiceMultipleCharge
([FromUri]MultipleChargeDto multipleCharge)
{
...
}
Please, note that the ajax method has a comment line. Using the hardcoded line, it works, multipleCharge object is not null, but if I uncomment the another line, it's a bad request in my browser.
Look at this.
Any idea about what's happening. Using the Chrome console, it looks ok; so I can't identify the error.
It is may be IIS problems with very long URL.
See this Issue with URL length in IIS7 (Windows Server 2008) question and related answers.
Also see this http://www.iis.net/configreference/system.webserver/security/requestfiltering documentation.
You could try to solve this problem by editing web.config. But also you could use POST method instead of GET and send your data in request body.

Ajax request, should it be POST or PUT

I have created a Spring MVC web app.
The app makes a few calls to the controller. These calls are close/open/end game.
I make these calls using Ajax, so I can handle a response on the top of the page.
ajaxPost = function (url, action, id, onSuccess, onError) {
$.ajax({
type: "POST",
url: url + "?" + action + "=" + id,
success: function(response) {
if(onSuccess !== null) {
onSuccess(response);
}
},
error: function(e) {
if(onError !== null) {
onError(e);
}
}
});
};
The question I have is that I'm using 'POST' for the Ajax request, is that correct, or should it be 'PUT'?
My controller has a default URL, and I'm using the param attribute to decide which method to call, as I have many buttons on the page.
#RequestMapping(params = "open", method = RequestMethod.POST)
#RequestMapping(params = "close", method = RequestMethod.POST)
It doesn't sit well with me that I'm using 'POST' for these calls. Maybe it should be 'PUT'...
Any suggestions? Does it matter?
It depends on what your request should do. So there's no general rule that you should use one over the other, they have different use cases.
POST for creating a record.
PUT for updating an existing record (or putting a record at a specified location/id).
See this wikipedia article for the definitions.
One thing to note is that PUT should be idempotent, doing the same PUT request multiple times should ideally produce the same result as doing a single PUT request. However, POST is not idempotent, so doing several POST requests should (or will) create multiple new records.
So after having read this you should check what your method does, and select the corresponding request method.
Both PUT and POST may create a new record; PUT may also update/change an existing record.
The difference between POST and PUT is that PUT is expected to address the record with it's ID, so that the server knows what ID to use when creating (or updating) the record, while POST expects the server to generate an ID for the record and return it to the client after the record has been created.
Thus, a POST is addressed to the resource as a collection: POST /resource, while PUT is addressed to a single item in the collection: PUT /resource/1
Use POST. Always use POST, unless you're absolutely rock-solid certain that PUT is properly supported by your hosting system.

Make Wordpress Ajax calls work with global variables to reduce database queries

I posted this earlier on wordpress.stackexchange.com. However, never got a reply. Hence, trying my luck here.
I am hereby providing a detailed description of what I need and what I have done for this issue of mine. I am open to any workable solution around what I have done or maybe new suggestions.
I need to make use of user data that is retrieved using the following:
$user_data = get_user_by('login', get_query_var('user_login'));
The above code uses the username passed as a query_var in the URL. All works until here.
I make use of the above code in several Ajax callbacks (handled by admin-ajax.php) on single page load. Since, the site is targeted as a high volume site. All these Ajax requests lead to several database query for the same data. So the obvious idea to save some database queries is to pass the data to a global variable like below:
$_GLOBALS['user_data'] = get_user_by('login', get_query_var('user_login'));
And then use the same in the Ajax callbacks. Here's problem. None of the Ajax callback functions see the global $user_data variable. Before you ask, yes I have declared the global inside callback as well.
So, the obvious answer would be: why not use wp_localize_script and pass the $user_data to the Ajax callback via javascript like bellow:
In PHP:
wp_localize_script('jquery', 'ajaxVars', array( 'ajaxurl' => admin_url('admin-ajax.php'), 'user_data' => $user_data));
In Javascript:
jQuery.ajax({
url: ajaxVars.ajaxurl,
type:'POST',
async: false,
cache: false,
timeout: 10000,
data: 'action=ajax_callback&user_data=' + ajaxVars.user_data,
success: function(value) {
alert(value);
},
error: function() {
alert(error);
}
});
However, this poses two questions:
Can an object that get_user_by('login', get_query_var('user_login')); returns be handled by wp_localize_script()?
If the answer to above question is yes, then would it not pose a security threat since the object would contain sensitive user information?
To overcome the global variable being not available to Ajax callbacks, I declared it directly in functions.php (without wrapping it inside a function). However, get_query_var('user_login') does not return any data when used directly inside functions.php making this futile exercise (You have to add it inside a function and call it via an action).
So, the question remains: how do I stop making $user_data = get_user_by('login', get_query_var('user_login')); calls for every Ajax request? Or is there a way I could get get_query_var('user_login') to work inside functions.php directly (without wrapping it inside a function) or a workaround?
Or maybe some completely new out of the box thinking?
All these Ajax requests lead to several database query for the same
data. So the obvious idea to save some database queries is to pass the
data to a global variable like below:
$_GLOBALS['user_data'] = get_user_by('login', get_query_var('user_login'));
And then use the same in the Ajax callbacks.
Each request that your application receives, AJAX or otherwise, lives completely in isolation: the code handling the requests does not share any state between them (besides whatever is persisted to a database). A global (or constant, or property, or variable, or anything) you define in one request will never be available to subsequent requests unless you store it somewhere.
There are a number of approaches to reducing the number of queries these requests are creating. One would be to retrieve the required user data on page load and pass it to subsequent requests. E.g.:
var user = 'someUser';
$.get('user-data.php?user=' + user, function(user_data) {
$.ajax('some-endpoint.php', {
type: 'POST',
data: { user: user_data },
success: function() { /* ... */ }
});
$.ajax('some-other-endpoint.php', {
type: 'POST',
data: { user: user_data },
success: function() { /* ... */ }
});
});
Alternatively, if it's the currently logged in user you're working with you can write their details to a JavaScript object on initial page load for use later.
var userData = <?php get_currentuserinfo(); echo json_encode($current_user); ?>;
Another option would be to ensure that the get_user_by results were being cached, either by Wordpress, MySQL or some other caching layer. That way it doesn't particularly matter how many times your code calls the method.
In general if lots of your endpoints are sharing functionality, you could probably stand to refactor some of that code.

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