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Connection reset issue in .net core api call (net::ERR_CONNECTION_RESET 200 (OK))

I have a .net core API service which is called from a angular client project.
When a user request a status of his payment, we will make call to this service api and this service will then call a payment gateway service to fetch the status of payment and the output result will return to the user.
When i try to integrate this i am facing this below error.
net::ERR_CONNECTION_RESET 200 (OK)
core.js:5967 ERROR Unknown Error
This above issue is not showing when i try to hit the service after putting one breakpoint. Its also returning the result.
This is how entire flow works
Client side call performs by user
this.dataservice.postFeed(method, JSON.stringify(this.initsearch)).subscribe(result => {
var response = result.body["data"];
console.log(response);
});
Server side code looks like
[HttpPost]
public async Task<IActionResult> Post([FromBody] ObjectModel searchValue)
{
ApiResponse<string> response = new ApiResponse<string>();
IBaseResult<string> result = await _adlerBo.GetPaymentStatus(searchValue);
response.Success = result.success;
response.Data = result.Data;
return Ok(response);
}
In BusinessObject.cs
public async Task<IBaseResult<string>> GetPaymentStatus(PaymentSearchModel requestModel){
string apiResponse = await PaymentStatusCheckUsingAPI(requestModel.orderid);
return apiResponse ;
}
private async Task<string> PaymentStatusCheckUsingAPI(string orderNumber)
{
string message = await PostPaymentRequestToGateway(statusApiUrl, authQueryUrlParam);
NameValueCollection param = await GetResponseMap(message);
string status = "";
string encResJson = "";
if (param != null && param.Count == 2)
{
for (int i = 0; i < param.Count; i++)
{
if ("status".Equals(param.Keys[i]))
{
status = param[i];
}
if ("enc_response".Equals(param.Keys[i]))
{
encResJson = param[i];
}
}
if (!"".Equals(status) && status.Equals("0"))
{
resJson = crypto.Decrypt(encResJson, workingKey);
}
else if (!"".Equals(status) && status.Equals("1"))
{
Console.WriteLine("failure response: " + encResJson);
}
}
return resJson;
}
private async Task<string> PostPaymentRequestToGateway(string queryUrl, string urlParam)
{
string message = "";
try
{
StreamWriter myWriter = null;// it will open a http connection with provided url
WebRequest objRequest = WebRequest.Create(queryUrl);//send data using objxmlhttp object
objRequest.Method = "POST";
//objRequest.ContentLength = TranRequest.Length;
objRequest.ContentType = "application/x-www-form-urlencoded";//to set content type
myWriter = new System.IO.StreamWriter(objRequest.GetRequestStream());
myWriter.Write(urlParam);//send data
myWriter.Close();//closed the myWriter object
// Getting Response
System.Net.HttpWebResponse objResponse = (System.Net.HttpWebResponse)objRequest.GetResponse();//receive the responce from objxmlhttp object
using (System.IO.StreamReader sr = new System.IO.StreamReader(objResponse.GetResponseStream()))
{
message = await sr.ReadToEndAsync();
//Response.Write(message);
}
}
catch (Exception exception)
{
Console.Write("Exception occured while connection." + exception);
}
return message;
}
private async Task<NameValueCollection> GetResponseMap(string message)
{
//await Task.Delay(2000); I did this with no Luck
NameValueCollection Params = new NameValueCollection();
if (message != null || !"".Equals(message))
{
string[] segments = message.Split('&');
foreach (string seg in segments)
{
string[] parts = seg.Split('=');
if (parts.Length > 0)
{
string Key = parts[0].Trim();
string Value = parts[1].Trim();
Params.Add(Key, Value);
}
}
}
return await Task.FromResult(Params);
}
Any idea how to fix this? Why its working when i put breakpoint and not otherwise.
Am i doing correct asynchronous implimentsion in my api?

Cancellation Token Disposed Exception

I had this piece of code that initially worked fine. However, After adding it to a class where I store my methods that are reused, it keeps failing. The exception that is caught states that the CancellationTokenSource has been Disposed. Can someone point me in the right direction?
I have tried creating a new client and Adding CancellationToken.None to the PutAsync() method from HTTPClient Class but it still fails with the CancellationTokenSource Disposed exception.
public async void AddProduct(Product product)
{
string storeId = "";
try
{
var storeData = JObject.Parse(Connect.Json).SelectToken("store").ToString();
var stores = JsonConvert.DeserializeObject<List<Store>>(storeData);
var store = stores[0];
storeId = store.Id;
store.Products.Add(product);
ProdInfo info = new Info();
foreach(Product p in store.Products)
{
info.AddedProducts = + p.Id;
}
var content = JsonConvert.SerializeObject(info);
using (Connect.Client)
using (var response = await Connect.Client.PutAsync(_url + "/stores/" + storeId, new StringContent(content)))
{
var cont = response.Content;
string result = await cont.ReadAsStringAsync();
if ((int)response.StatusCode == 200)
{
this.JobResult = result;
//this.JobResult = "Store has been successfully updated";
}
else
{
this.JobResult = result;
//this.JobResult = "Store was not updated!";
}
}
}
catch (Exception ex)
{
//this.JobResult = "Store has not been updated due to an error.";
this.JobResult = ex.Message;
}
}

I was able to solve this by simple removing 'using(Connect.Client)' from all of my methods. As #sellotape stated, They were disposing of the HttpClient before I was able to use it again. Thank you all for your contributions.

async processing in c#

I have a service that implements functionality to return data from sentiment analysis APIs. The client can request results from one or all engines and I want to collate all the data together. I want to process these async and wait for them all to complete before returning the result set. I'm new to async programming and I really cant figure out how to arrange the code and how to implement it syntactically. Here's an EXAMPLE of what I'm TRYING to achieve (I know this doesn't work, but you get the idea; hopefully :-) ):
private ISentimentResponse ProcessRequest(ISentimentRequest request, SentimentEngineServices selectedEngines)
{
SentimentResponse response = new SentimentResponse();
List<Task> taskList = new List<Task>();
foreach (SentimentEngineServices engineService in (SentimentEngineServices[])Enum.GetValues(typeof(SentimentEngineServices)))
{
if (((int)engineService & (int)selectedEngines) > 0)
{
ISentimentEngine engine = _engineFactory.GetSentimentEngine(engineService, null);
Task<ISentimentEngineResult> task = new Task<ISentimentEngineResult>(engine.AnalyseSentimentASync(request));
taskList.Add(task);
}
}
if (taskList.Count > 0)
{
ISentimentEngineResult[] results = Task<ISentimentEngineResult>.WaitAll(taskList);
foreach (result in results)
response.Add(results);
}
return response;
}
The engine has the following code implementation of engine.AnalyseSentimentASync:
public ISentimentEngineResult AnalyseSentiment(ISentimentRequest request)
{
try
{
MultiLanguageBatchInput sentimentList = SentimentRequestToMicrosoftBatchInput(request, Properties.Settings.Default.DefaultLanguage);
SentimentBatchResult sentiment = _client.Sentiment(sentimentList);
KeyPhraseBatchResult keyPhrases = _client.KeyPhrases(sentimentList);
return MicrosoftBatchResultsToSentimentEngineResult(sentiment, keyPhrases);
}
catch (Exception ex)
{
_logger.LogMessage(ex,$"{EngineName} threw an unknown exception: ", LoggingLevel.Error);
throw;
}
}
public async Task<ISentimentEngineResult> AnalyseSentimentAsync(ISentimentRequest request)
{
return AnalyseSentiment(request);
}
What do I need to do and is there any better way to achieve this?
I've looked everywhere for an example but I cant find one that addresses my implementation requirements, or the whole approach is completely wrong!
Thanks all,
Stu.

This is how you can convert it to async:
public async Task<ISentimentEngineResult> AnalyseSentimentAsync(ISentimentRequest request)
{
try
{
MultiLanguageBatchInput sentimentList = SentimentRequestToMicrosoftBatchInput(request, Properties.Settings.Default.DefaultLanguage);
SentimentBatchResult sentiment = await _client.SentimentAsync(sentimentList);
KeyPhraseBatchResult keyPhrases = await _client.KeyPhrasesAsync(sentimentList);
return MicrosoftBatchResultsToSentimentEngineResult(sentiment, keyPhrases);
}
catch (Exception ex)
{
_logger.LogMessage(ex,$"{EngineName} threw an unknown exception: ", LoggingLevel.Error);
throw;
}
}
private async Task<ISentimentResponse> ProcessRequestAsync(ISentimentRequest request, SentimentEngineServices selectedEngines)
{
SentimentResponse response = new SentimentResponse();
List<Task<ISentimentEngineResult>> taskList = new List<Task<ISentimentEngineResult>>();
foreach (SentimentEngineServices engineService in (SentimentEngineServices[])Enum.GetValues(typeof(SentimentEngineServices)))
{
if (((int)engineService & (int)selectedEngines) > 0)
{
ISentimentEngine engine = _engineFactory.GetSentimentEngine(engineService, null);
Task<ISentimentEngineResult> task = engine.AnalyseSentimentASync(request);
taskList.Add(task);
}
}
if (taskList.Count > 0)
{
ISentimentEngineResult[] results = await Task.WhenAll(taskList);
foreach (result in results)
response.Add(results);
}
return response;
}
Remember that you have to call it from some kind of event handler. I don't know what framework you are using (wpf, asp.net, windows service, webapi).

Ok, so here it is:
public ISentimentResponse AnalyseSentiment(ISentimentRequest request, SentimentEngineServices selectedEngines)
{
if (selectedEngines == SentimentEngineServices.None) throw new ArgumentException(nameof(selectedEngines));
ValidateRequest(request);
return ProcessRequestAsync(request, selectedEngines).Result;
}
private async Task<ISentimentResponse> ProcessRequestAsync(ISentimentRequest request, SentimentEngineServices selectedEngines)
{
SentimentResponse response = new SentimentResponse();
List<Task<ISentimentEngineResult>> taskList = new List<Task<ISentimentEngineResult>>();
foreach (SentimentEngineServices engineService in (SentimentEngineServices[])Enum.GetValues(typeof(SentimentEngineServices)))
{
if (((int)engineService & (int)selectedEngines) > 0)
{
ISentimentEngine engine = _engineFactory.GetSentimentEngine(engineService, null);
Task<ISentimentEngineResult> task = engine.AnalyseSentimentASync(request);
taskList.Add(task);
}
}
if (taskList.Count > 0)
{
ISentimentEngineResult[] results = await Task.WhenAll(taskList);
foreach (var result in results)
response.Add(result);
}
return response;
}
And the sentiment interface implementation:
public async Task<ISentimentEngineResult> AnalyseSentiment(ISentimentRequest request)
{
try
{
MultiLanguageBatchInput sentimentList = SentimentRequestToMicrosoftBatchInput(request, Properties.Settings.Default.DefaultLanguage);
SentimentBatchResult sentiment = await _client.SentimentAsync(sentimentList);
KeyPhraseBatchResult keyPhrases = await _client.KeyPhrasesAsync(sentimentList);
return MicrosoftBatchResultsToSentimentEngineResult(sentiment, keyPhrases);
}
catch (Exception ex)
{
_logger.LogMessage(ex,$"{EngineName} threw an unknown exception: ", LoggingLevel.Error);
throw;
}
}
Thanks FCin.

Why detailed error message is not passed to HttpClient?

I am using the default Web Api controller that is auto generated. I am testing the validation and error handling in the client side. But somehow I have realised that the detail error message is not passed to client. Either if I throw HttpResponseException or returning IHttpActionResult in both cases the client is seeing only "Bad Request" but not the detailed message. Can anyone explain what is going wrong please?
public IHttpActionResult Delete(int id)
{
if (id <= 0)
{
var response = new HttpResponseMessage(HttpStatusCode.NotFound)
{
Content = new StringContent("Id should be greater than zero.", System.Text.Encoding.UTF8, "text/plain"),
StatusCode = HttpStatusCode.NotFound
};
throw new HttpResponseException(response) // Either this way
}
var itemToDelete = (from i in Values
where i.Id == id
select i).SingleOrDefault();
if (itemToDelete == null)
{
return BadRequest(string.Format("Unable to find a value for the Id {0}", id)); // Or This way
}
Values.Remove(itemToDelete);
return Ok();
}
client code is as:
private async static Task DeleteValue(int id)
{
var url = "http://localhost:13628/api/Values/" + id;
using (var client = new HttpClient())
{
var response = await client.DeleteAsync(url);
if (response.IsSuccessStatusCode)
{
await ReadValues();
}
else
{
Console.WriteLine(response.ReasonPhrase);
Console.WriteLine(response.StatusCode);
}
}
}
None of the above works??
Thx

In your client side change Console.WriteLine(response.ReasonPhrase);
to Console.WriteLine(response.Content.ReadAsStringAsync().Result);
and it will give the detailed error message.

Replace below code into Web API delete action. Use HttpResponseMessage as return tpye for api instead of IHttpActionResult
[HttpDelete]
[Route("{id:int:min(1)}")]
public async Task<HttpResponseMessage> DeleteAsync(int id)
{
if(id < 0 )
{
return await Task.FromResult<HttpResponseMessage>(Request.CreateResponse<string>(HttpStatusCode.BadRequest, "Id should be greater than zero."));
}
try
{
var itemToDelete = (from i in Values
where i.Id == id
select i).SingleOrDefault();
if (itemToDelete == null)
{
return await Task.FromResult<HttpResponseMessage>(Request.CreateResponse<string>(HttpStatusCode.NotFound,
string.Format("Unable to find a value for the Id {0}", id)));
}
Values.Remove(itemToDelete);
return await Task.FromResult<HttpResponseMessage>(Request.CreateResponse(HttpStatusCode.OK));
}
catch (Exception ex)
{
return Request.CreateResponse<string>(HttpStatusCode.InternalServerError, "Something went wrong."); // Default message if exception occured
}
}
And client Side:
private async static Task DeleteValue(int id)
{
var url = "http://localhost:13628/api/Values/" + id;
using (var client = new HttpClient())
{
var response = await client.DeleteAsync(url);
if (response.IsSuccessStatusCode)
{
await ReadValues();
}
else
{
var errorMessage = Newtonsoft.Json.JsonConvert.DeserializeObject<string>(await response.Content.ReadAsStringAsync());
// Here Newtonsoft.Json Package is used to deserialize response content
Console.WriteLine(errorMessage);
Console.WriteLine(response.StatusCode);
}
}
}
Above code is working at my side.

reduce complexity of service class

I am developing a web api using WCF Web Api preview 5. At the moment I have a resource class fully functional, how ever I noticed my methods inside this resouce are getting complex.
For example:
[WebInvoke(UriTemplate = "{EhrID}/PhysicalTest",Method="POST")]
public HttpResponseMessage<DTO.PhysicalTest> PostPhysicalTest(int EhrID, DTO.PhysicalTest PhysicalTestDTO)
{
var EHR = repository.FindById(EhrID);
var PhysicalTest = Mapper.Map<DTO.PhysicalTest, PhysicalTest>(PhysicalTestDTO);
if (PhysicalTest == null)
{
var response = CreateResponseForException("No object to store", HttpStatusCode.BadRequest);
throw new HttpResponseException(response);
}
try
{
if (EHR.PhysicalTests == null)
{
EHR.PhysicalTests = new List<PhysicalTest>();
}
PhysicalTest.CreationDate = DateTime.Now;
EHR.PhysicalTests.Add(PhysicalTest);
_unitOfWork.Commit();
return new HttpResponseMessage<DTO.PhysicalTest>(PhysicalTestDTO, HttpStatusCode.Created);
}
catch (Exception ex) {
var response = CreateResponseForException("Cannot create Physical Test", HttpStatusCode.InternalServerError);
throw new HttpResponseException(response);
}
}
As you may notice this method has the task of posting a new Physical Test, but it's actually validating my model too (I'm missing lots of validations still, property validations), which should not be this class concern. If there any approachable way to reduce the complexity of the methods inside de resource?

I would split it up into smaller more focused methods. I might also start using instance variables instead of passing all these arguments around, but for the sake of this post I've rewritten it without pushing stuff to instance variables.
[WebInvoke(UriTemplate = "{EhrID}/PhysicalTest",Method="POST")]
public HttpResponseMessage<DTO.PhysicalTest> PostPhysicalTest(int EhrID, DTO.PhysicalTest PhysicalTestDTO)
{
var EHR = repository.FindById(EhrID);
var PhysicalTest = Mapper.Map<DTO.PhysicalTest, PhysicalTest>(PhysicalTestDTO);
if (PhysicalTest == null)
{
var response = CreateResponseForException("No object to store", HttpStatusCode.BadRequest);
throw new HttpResponseException(response);
}
PostPhysicalTest(EHR, PhysicalTest);
return new HttpResponseMessage<DTO.PhysicalTest>(PhysicalTestDTO, HttpStatusCode.Created);
}
private void PostPhysicalTest(EHR ehr, PhysicalTest physicalTest)
{
try
{
CreatePhysicalTest(ehr, physicalTest);
}
catch (Exception ex) {
var response = CreateResponseForException("Cannot create Physical Test", HttpStatusCode.InternalServerError);
throw new HttpResponseException(response);
}
}
private void CreatePhysicalTest(EHR ehr, PhysicalTest physicalTest)
{
if (ehr.PhysicalTests == null)
{
ehr.PhysicalTests = new List<PhysicalTest>();
}
physicalTest.CreationDate = DateTime.Now;
ehr.PhysicalTests.Add(physicalTest);
_unitOfWork.Commit();
}