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Flutter with GetX, get connect don't calling to the setted adress

I'm trying to get a response from a web api(C#), but, in a specific method, the end point address is pointed to the port the front end is running on, but in the others methods it's working as well.
Future<void> onInit() async {
httpClient.baseUrl = await baseUrlGetter();
httpClient.addRequestModifier((Request request) {
request.headers['Accept'] = 'application/json';
request.headers['Content-Type'] = 'application/json';
request.headers['origemAcesso'] = 't2painel';
return request;
});
httpClient.addAuthenticator((Request request) {
var token = _storageService.token;
var headers = {'Authorization': "Bearer $token"};
request.headers.addAll(headers);
return request;
});
super.onInit();
}
Ahead, it'ts the onInit method in API class, the function baseUrlGetter is working, returnig the rigth url of the API.
But, in the method below:
Future<ImageModel> fetchDistribuidorImage() async {
var response = _errorHandler(await get('/api/Imagens/DistribuidorImagem'));
var data = ImageModel.fromJson(response.body);
return data;
}
Take a look to this images (read the images descriptions)
Only in the method "fetchDistribuidorImage" is not correct.

Http Client did not return any value and not moved another line of code

When I call HTTP client like below this code did not return any response value and also did not move next line of code. just hanged.
How to solve this issue?
I called from another class file, here this function want return proper a integer value and also HTTP response.
// call api
HttpResponseMessage response = await client.PostAsJsonAsync("System", new Systemmodel
{
GuidID = System.Guid.NewGuid().ToString(),
SystemIP = "124.0.098",
SystemUserName = string.IsNullOrEmpty(SystemName)
? System.Environment.MachineName
: SystemName,
SystemOS = "Windows OS",
CompanyGUID = Ad`enter code here`minName
});

Web API async Task await blocking main thread

We have a three tier infrastructure (front end which is all Web API 2, Middleware which accepts API calls from front end and runs business logic and databases access, then the DB)
I'm trying to find out why our app locks up when I take the middle tier down. We use Memcached for all the reads and the front end serves the cached data just fine, but one of the calls that is made checks to see if the user is logged in. Running on my local machine with one app pool, that call locks the thread (I think) and prevents the rest of the calls from doing anything until the timeout on the autologin call expires.
The code path looks like this:
call to api/autologin --> front end API calls Client.SendAsync (our custom method for passing along data to the middleware), this tries to call the middlewware by using HttpClient.SendAsAsync with a timeout of 3 minutes (Probably should shorten this)
My expectation is that this should release this thread while we are waiting. That does not appear to be the result.
The REALLY weird thing is that when the middleware is down the Client.SendAsync gets ran MANY time, like 10. I thought this was maybe HTTP 2.0 in Chrome, but I switched to Fiddler and it did the same thing. Very weird.
So, two questions.
1. What's with the multiple calls?
2. Why do the threads appear to be getting locked?
Here's the code.
/// <summary>
/// Auto login user if they have the persistent cookies.
/// </summary>
/// <returns>The groups the logged in user has access to in the form of a
LoggedInUserData object.</returns>
[Route("api/cms/autologin/")]
[HttpGet]
public async Task<HttpResponseMessage> AutoLogin()
{
HttpResponseMessage response = await Client.SendAsync(this.Request);
return this.LoginCacheHelper(response);
}
That calls
public static async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request)
{
return await Client.SendAsync<string>(request, null, null, false);
}
Which calls
public static async Task<HttpResponseMessage> SendAsync<T>(HttpRequestMessage request, T content = null, string route = null, bool isFile = false, TimeSpan? timeout = null) where T : class
{
// Validate all internal certs.
ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };
// Determine the route and make sure route has a starting forward slash.
if (!string.IsNullOrWhiteSpace(route) && route.StartsWith("http"))
{
// Check to make sure this is a selinc.com domain for security purposes.
if (Sel.Utils.Validation.UriValidation.IsSelincDomain(route))
{
request.RequestUri = new Uri(route);
}
else
{
return new HttpResponseMessage(HttpStatusCode.BadRequest);
}
}
else
{
string middlewareRoute = GetRoute(route, request);
// Change Uri to middle ware.
request.RequestUri = new Uri(Config.MwareSiteUrl + middlewareRoute);
}
// Remove host header
request.Headers.Host = string.Empty;
// Set content of request.
// File content will be kept on the request as is.
if (content != null && !isFile)
{
request.Content = new ObjectContent<T>(content, new JsonMediaTypeFormatter());
}
else if (!isFile)
{
request.Content = null;
}
// Client handler set use cookies to false which will pass along the current cookies
HttpClientHandler clientHandler = new HttpClientHandler() { UseCookies = false };
// The HttpClient object
HttpClient client = new HttpClient(clientHandler);
client.Timeout = timeout ?? new TimeSpan(0, 3, 0);
// Send the request
return await client.SendAsync(request);
}
Adding image of the Network log in Chrome to illustrate the behavior.
Note that if I remove the API call to the autologin, everything works fine. It's the only call in this stack that hits the back end.
Also note: If I modify the SendAsync method to just return a new HttpResponseMessage (and thus do no work) then the autologin basically does nothing, returns quickly and site loads as it should, with the middleware server down. This is just to prove that it is the autologin API call causing the problem. The autologin API call is the only method calling SendAsync at this time so it's a valid test.
// Send the request
////return await client.SendAsync(request);
return new HttpResponseMessage();

MVC4 Async Controller Action not completed

I have an async Action that gets called by jquery ajax request:
View:
$.ajax({
url: "#Url.Action("StartVerification", "Devices")",
global: false,
data: JSON.stringify(machineIds),
contentType: 'application/json',
type: 'POST'
...
Controller:
[HttpPost]
[SessionExpireFilter(Order = 1)]
[CheckPermissions(Order = 2)]
[AjaxMessagesFilter(Order = 3)]
[AsyncTimeout(30000, Order = 4)]
[HandleError(ExceptionType = typeof(TimeoutException), View = "TimeoutError", Order = 5)]
public async Task<JsonResult> StartVerification(ICollection<Machine> machines)
{
Dictionary<int, bool> collection = new Dictionary<int, bool>();
foreach (var machine in machines)
{
Response response = new Response();
try
{
response = await this.deviceRepository.StartVerification(machine);
}
catch (Exception ex)
{
response.Success = false;
}
collection.Add(machine.MachineID, response.Success);
}
return this.Json(collection.ToDictionary(x => x.Key.ToString(), y => y.Value));
}
Web service call:
public async Task<Response> StartVerification(Machine machine, CancellationToken cancelToken = default(CancellationToken))
{
WebService WebServiceForTask = WebServiceFactory.NewInstance;
return await Task.Run(() => WebServiceForTask.StartVerificationForWebSite(machine.SiteID, machine.MachineID));
}
The problem I'm having is that when StartVerification action is executed which calls then queries a web service. The query for that result may take up to several seconds during which time a user may press a refresh button of their browser. What's the best way to handle this scenario and simply abort the call etc.
EDIT:
Maybe I'm asking the question wrong. The issue here is that when I StartVerification and hit refresh page F5 the page will NOT refresh until I get a response from webservice...and it looks like Action is not run async. I want it to work so that if a controller action is already called and waiting on a response from webservice I still should be able to simply browse away from the page that I'm calling the action from.

What's the best way to handle this scenario and simply abort the call etc
You could subscribe to the onbeforeunload event before you start the AJAX request:
window.onbeforeunload = function() {
return 'There\'s an ongoing operation. If you leave this page you might lose some data';
};
and when the AJAX call completes remove the subscription to this event.

Since you have an AsyncTimeout attribute, you should take a CancellationToken that represents that timeout.
There is another CancellationToken that represents a user disconnecting early (Response.ClientDisconnectedToken). However, there is currently a race condition on ClientDisconnectedToken so I do not recommend using it with the current release of ASP.NET (4.5). The best policy right now is to honor the AsyncTimeout and just ignore early client disconnects.
However, if you really wanted to detect client disconnect, you could periodically poll for Response.IsClientConnected.

ASP.Net Asynchronous HTTP File Upload Handler

I'm trying to make a file upload handler in C# that is asynchronous and can provide updates on progress of the file through AJAX asynchronous requests. Basically if the request is a POST it loads some information into the session and then starts the upload, if the request was a GET it returns the current state of the upload (bytes uploaded, total bytes, etc). I'm not entire sure that it needs to be an asynchronous handler but the files could be quite large so I thought that would work best. For the base async handler I used something very similar to the handler in this MSDN article. I've posted below some key sections of my code below. The issue I'm having is that I don't receive any of the GET information back until the POST has completed. I will mention that in this example I am using jQuery for GET requests and BlueImp for posting the file.
The HTML and JavaScript
<input id="somefile" type="file" />
$(function () {
name = 'MyUniqueId130';
var int = null;
$('#somefile').fileupload({
url: '/fileupload.axd?key='+name,
done: function (e, data) { clearInterval(int); }
});
$('#somefile').ajaxStart(function(){
int = setInterval(function(){
$.ajax({
url: '/fileupload.axd?key='+name,
dataType: 'json',
async: true
})
.done(function(e1, data1){
if(!e1.InProgress || e1.Complete || e1.Canceled)
clearInterval(int);
});
}, 10000)});
});
The Asynchronous Process Request Method just calls the correct method whether it's a POST or GET to one of the following then calls CompleteRequest to end the request:
private static void GetFilesStatuses(HttpContext context)
{
string key = context.Request.QueryString["key"];
//A dictionary of <string, UploadStatus> in the session
var Statuses = GetSessionStore(context);
UploadStatus ups;
if (!String.IsNullOrWhiteSpace(key))
{
if (Statuses.TryGetValue(key, out ups))
{
context.Response.StatusCode = (int)HttpStatusCode.OK;
context.Response.Write(CreateJson(ups));
}
else
{
context.Response.StatusCode = (int)HttpStatusCode.NotFound;
}
}
else
{
context.Response.StatusCode = (int)HttpStatusCode.OK;
context.Response.Write(CreateJson(Statuses.Values));
}
}
private static void UploadFile(HttpContext context)
{
var Statuses = GetSessionStore(context);
string key = context.Request.QueryString["key"];
if (String.IsNullOrWhiteSpace(key))
{
context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
return;
}
HttpPostedFile file = context.Request.Files[0];
string extn = file.FileName.LastIndexOf('.') == -1 ? "" :
file.FileName.Substring(file.FileName.LastIndexOf('.'), (file.FileName.Length - file.FileName.LastIndexOf('.')));
string temp = GetTempFileName(path, extn);
UploadStatus status = new UploadStatus()
{
FileName = file.FileName,
TempFileName = temp,
Path = path,
Complete = false,
Canceled = false,
InProgress = false,
Success = true,
BytesLoaded = 0,
TotalBytes = file.ContentLength
};
Statuses.Add(key, status);
byte[] buffer = new byte[bufferSize];
int byteCount = 0;
using (var fStream = System.IO.File.OpenWrite(context.Request.MapPath(path + temp)))
{
uploads.Add(status);
while ((byteCount = file.InputStream.Read(buffer, 0, bufferSize)) > 0 && !status.Canceled)
{
status.InProgress = true;
status.BytesLoaded += byteCount;
fStream.Write(buffer, 0, byteCount);
}
status.Complete = !status.Canceled;
status.InProgress = false;
status.Success = true;
if (status.Canceled)
{
Statuses.Remove(temp);
}
context.Response.StatusCode = (int)HttpStatusCode.OK;
}
}
I've tried many things such as non-async handlers, async handlers, making sure the JavaScript is runnning async, but at this point I think I need some different eyes on the problem so thank you for any assistance anyone can provide.

I assume you're using the default ASP.Net Session manager and I see that you call GetSessionStore to get your session. Unfortunately the default Session manager serializes all requests when a call requires write access to the Session Store. This StackOverflow question and this MSDN arcle on Session State have some very useful information on Session State and it's locking behaviors.
Now, To take care of your problem, you're going to have to do a couple things which depend on whether you're using MVC controllers or if you're writing a custom IHttpHandler.
If you're writing your own IHttpHandler, make sure you do not have the IRequiresSessionState or IReadOnlySessionState interfaces added to your handler. In doing so, the pipeline will skip looking for a session and go straight to processing. context.Session will be null in this situation.
If you're using MVC to process the request, you'll need to decorate your controller class with the SessionState attribute passing in the SessionStateBehavior of SessionStateBehavior.Disabled.
In either case you won't be able to rely on the Session object to store your upload statuses. You can create a static ConcurrentDictionary keyed off of their SessionID (which you'll either need to pass in the upload query string or read the cookie yourself, calling Session.SessionId will just block you again) and store your upload statuses in there (which look like they're Concurrent* as well).
Another option would be to replace the SessionStateProvider with your own custom provider but that might be overkill in this situation.