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PostAsync call vanishes and web page becomes available again

I have a web page that I'm trying to call a web service and I'm having it skip out of the process when called.
Here's what I'm referring to...
When I call this method after the customer enters in their check information:
public CheckInfo SubmitCheck(CheckInfo checkInfo)
{
try
{
var check = new Check();
check.account_number = checkInfo.CheckAccountNumber;
check.transit_number = checkInfo.CheckRoutingNumber;
check.amount = checkInfo.Amount.ToString();
check.check_number = checkInfo.CheckNumber;
check.bill_to_city = checkInfo.City;
check.bill_to_country = "US";
check.bill_to_postal_code = checkInfo.Zip;
check.bill_to_street = checkInfo.Street;
check.bill_to_state = checkInfo.State;
check.name_on_check = checkInfo.NameOnCheck;
check.transaction_type = "sale";
check.account_type = checkInfo.AccountType;
check.check_type = checkInfo.CheckType;
var ent = new SuburbanPortalEntities();
var gatewaySettings = (from x in ent.GatewayUsers
where x.TokenId == CurrentCustomerSession.Current.TokenId &&
x.Gateway.Name == "DirectAch2"
select x).FirstOrDefault();
var credentials = new Authentication();
credentials.password = gatewaySettings.Password;
credentials.username = gatewaySettings.UserName;
var response = Process.SubmitCheck(credentials, check).Result;
The public class that calls the private class:
public static async Task<Response> SubmitCheck(Authentication authentication, Check check)
{
return await Submit(authentication, check, PaymentTypes.Check);
}
The SubmitCheck Method:
private static async Task<Response> Submit(Authentication authentication, Object payment, PaymentTypes paymentType)
{
var resp = new Response();
try
{
var client = new HttpClient();
var bodyjson = JsonConvert.SerializeObject(authentication);
var bodycontent = new StringContent(bodyjson, Encoding.UTF8, "application/json");
var authenticationPost =
await client.PostAsync("https://someplace.com/api/v2/Identity", bodycontent);
var bodyResponseJson = await authenticationPost.Content.ReadAsStringAsync();
When I get to this line, it just returns out of the method and it doesn't continue on with anything, it's like I never executed this method.
var authenticationPost =
await client.PostAsync("https://someplace.com/api/v2/Identity", bodycontent);
No other code is executed after this line. It just stops and the web page becomes available again. I have the method wrapped in a try catch but the catch isn't.. catching anything.
I'm at a loss at this poing, any suggestions?
EDIT#1
I wrapped the line in a try catch as suggested.
try
{
authenticationPost =
await client.PostAsync("https://someplace.com/api/v2/Identity", bodycontent);
}
catch (Exception e)
{
Console.WriteLine(e);
throw;
}
It's stepping out of the try/catch and never executing any more code after that. No exception is caught, nothing, it just runs the line and leaves the method.

Here's your problem:
var response = Process.SubmitCheck(credentials, check).Result;
Don't block on async code, as I describe on my blog. This is a common mistake for those new to async/await. Instead of Result, use await:
public async Task<CheckInfo> SubmitCheck(CheckInfo checkInfo)
{
...
var response = await Process.SubmitCheck(credentials, check);
Note that you'd then need to await the call to SubmitCheck, and so on. It's async all the way.
Side note: I recommend using the standard pattern of *Async suffixes on your method names; it makes it clearer in the code that their return values need to be awaited:
public async Task<CheckInfo> SubmitCheckAsync(CheckInfo checkInfo)
{
...
var response = await Process.SubmitCheckAsync(credentials, check);

Performance hit when converting IEnumerable to List of Tasks

public async Task<List<usp_TeamMeetingGetAll_Result>> TeamsMeetingReportGetAll(bool activeOnly)
{
List<usp_TeamMeetingGetAll_Result> teamMeetingGetAllResults = _db
.usp_TeamMeetingGetAll(activeOnly)
.ToList();
IEnumerable<Task<usp_TeamMeetingGetAll_Result>> taskListQuery =
from teamMeetingGetAllResult in teamMeetingGetAllResults
select TeamsMeetingGet(teamMeetingGetAllResult);
List<Task<usp_TeamMeetingGetAll_Result>> taskList = taskListQuery.ToList();
usp_TeamMeetingGetAll_Result[] results = await Task.WhenAll(taskList);
return results.OrderBy(r => r.DisplayStartDate).ToList();
}
I'm trying to figure out why line 3 (the taskList assignment) takes 7-8 seconds to execute. Line 1 calls a stored proc and puts the results (26 rows, about 15 columns) in a list and takes about 1.5 seconds. Line 2 takes less than a millisecond. Line 4 takes about 4 seconds for all async tasks to complete.
Edit: Okay, thanks to the answers below I understand that:
List<Task<usp_TeamMeetingGetAll_Result>> taskList = taskListQuery.ToList();
is causing calls to TeamsMeetingGet. I should have checked that before.
TeamsMeetingGet is making a aync call to a web API, waiting for the results, populating some properties of the usp_TeamMeetingGetAll_Result object with the results, and passing it back.
public async Task<usp_TeamMeetingGetAll_Result> TeamsMeetingGet(usp_TeamMeetingGetAll_Result teamMeetingGetAllResult)
{
//OnlineMeeting onlineMeeting = await TeamsMeetingGet(teamMeetingGetAllResult.JoinWebUrl);
HttpClient client = GraphHelper.GetAuthenticatedHttpClient();
string request =
"users/xxxxxxxxxx/onlineMeetings?$filter=JoinWebUrl%20eq%20'" + HttpUtility.UrlEncode(teamMeetingGetAllResult.JoinWebUrl) + "'";
var response = await client.GetAsync(request);
var result = await response.Content.ReadAsStringAsync();
var jresult = JObject.Parse(result);
var onlineMeetings = jresult["value"].ToObject<OnlineMeeting[]>();
if (onlineMeetings[0].Id != null)
{
teamMeetingGetAllResult.NumAttendees = onlineMeetings[0].Participants.Attendees.Count();
teamMeetingGetAllResult.Subject = onlineMeetings[0].Subject;
//More assignments
}
else
{
teamMeetingGetAllResult.NumAttendees = 0;
teamMeetingGetAllResult.Subject = "";
}
return teamMeetingGetAllResult;
}
If I have 100 rows, I'd like to call TeamsMeetingGet 100 times simultaneously, instead of synchronously. Is this how I do it?
I asked for the GetAuthenticatedHttpClient code and got back:
public class GraphHelper
{
private static string _graphClientSecret = ConfigurationManager.AppSettings["graphClientSecret"];
private static string _graphClientId = ConfigurationManager.AppSettings["graphClientId"];
private static string _graphTenantId = ConfigurationManager.AppSettings["graphTenantId"];
public static HttpClient GetAuthenticatedHttpClient()
{
IConfidentialClientApplication app;
var clientId = _graphClientId;
var tenantID = _graphTenantId;
app = ConfidentialClientApplicationBuilder.Create(clientId)
.WithClientSecret(_graphClientSecret)
.WithAuthority(new Uri("https://login.microsoftonline.com/" + tenantID))
.Build();
string[] scopes = new string[] { "https://graph.microsoft.com/.default" };
AuthenticationResult result = null;
try
{
result = app.AcquireTokenForClient(scopes)
.ExecuteAsync().Result;
}
catch (MsalUiRequiredException ex)
{
// The application doesn't have sufficient permissions.
// - Did you declare enough app permissions during app creation?
// - Did the tenant admin grant permissions to the application?
throw ex;
}
catch (MsalServiceException ex) when (ex.Message.Contains("AADSTS70011"))
{
// Invalid scope. The scope has to be in the form "https://resourceurl/.default"
// Mitigation: Change the scope to be as expected.
throw ex;
}
catch (Exception ex)
{
throw ex;
}
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("bearer", result.AccessToken);
client.BaseAddress = new Uri("https://graph.microsoft.com/v1.0/");
return client;
}
}

Recursive method is returning first iteration object C#

static void Main(string[] args)
{
token objtoken = new token();
var location = AddLocations();
OutPutResults outPutResultsApi = new OutPutResults();
GCPcall gCPcall = new GCPcall();
OutPutResults finaloutPutResultsApi = new OutPutResults();
var addressdt = new AddressDataDetails();
finaloutPutResultsApi.addressDatas = new List<AddressDataDetails>();
Console.WriteLine("Hello World!");
List<string> placeId = new List<string>();
var baseUrl = "https://maps.googleapis.com/maps/api/place/textsearch/json?";
var apiKey = "&key=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx".Trim();
foreach (var itemlocations in location)
{
var searchtext = "query=" + itemlocations.Trim();
var finalUrl = baseUrl + searchtext + apiKey;
gCPcall.RecursiveApiCall(finalUrl, ref placeId, objtoken.NextToken);
}
var ids = gCPcall.myPalceid;
}
public List<string> RecursiveApiCall(string finalUrl, ref List<string> placeId, string nextToken = null)
{
try
{
var token = "&pagetoken=" + nextToken;
using (var client = new HttpClient())
{
var responseTask = client.GetAsync(finalUrl + token);
responseTask.Wait();
var result = responseTask.Result;
if (result.IsSuccessStatusCode)
{
var readTask = result.Content.ReadAsStringAsync();
readTask.Wait();
var students = readTask.Result;
Rootobject studentsmodel = JsonConvert.DeserializeObject<Rootobject>(students);
nextToken = studentsmodel.next_page_token;
foreach (var item in studentsmodel.results)
{
placeId.Add(item.place_id);
}
}
}
if (nextToken != null)
{
RecursiveApiCall(finalUrl, ref placeId, nextToken);
}
return placeId;
}
catch (Exception ex)
{
throw;
}
}
My recursive method has some issue. Here whenever I am debugging this code it work fine. It goes in recursive call twice.
As debugging result I am getting list place_id with 20 items in first call and next call 9 items total 29 items in place_id object which is correct in static main method.
But if I run without debugging mode I am getting only 20 place_id. next recursive iteration data is missing even if it has next valid token.
I don't have any clue why this is happening. Can someone tell me what is the issue with my code?

Here are my suggestions, which may or may not solve the problem:
// First of all, let's fix the signature : Go async _all the way_
//public List<string> RecursiveApiCall(string finalUrl, ref List<string> placeId, string nextToken = null)
// also reuse the HttpClient!
public async Task ApiCallAsync(HttpClient client, string finalUrl, List<string> placeId, string nextToken = null)
{
// Loop, don't recurse
while(!(nextToken is null)) // C# 9: while(nextToken is not null)
{
try
{
var token = "&pagetoken=" + nextToken;
// again async all the way
var result = await client.GetAsync(finalUrl+token);
if (result.IsSuccessStatusCode)
{
// async all the way!
var students = await result.Content.ReadAsStringAsync();
Rootobject studentsmodel = JsonConvert.DeserializeObject<Rootobject>(students);
nextToken = studentsmodel.next_page_token;
foreach (var item in studentsmodel.results)
{
// Will be reflected in main, so no need to return or `ref` keyword
placeId.Add(item.place_id);
}
}
// NO recursion needed!
// if (nextToken != null)
// {
// RecursiveApiCall(finalUrl, ref placeId, nextToken);
// }
}
catch (Exception ex)
{
// rethrow, only is somewhat useless
// I'd suggest using a logging framework and
// log.Error(ex, "Some useful message");
throw;
// OR remove try/catch here all together and wrap the call to this method
// in try / catch with logging.
}
}
Mind that you'll need to make your main :
async Task Main(string[] args)
and call this as
await ApiCallAsync(client, finalUrl, placeId, nextToken);
Also create an HttpClient in main and reuse that:
"HttpClient is intended to be instantiated once and re-used throughout the life of an application. Instantiating an HttpClient class for every request will exhaust the number of sockets available under heavy loads. This will result in SocketException errors." - Remarks
... which shouldn't do much harm here, but it's a "best practice" anyhow.
Now, as to why you get only 20 instead of expected 29 items, I cannot say if this resolves that issue. I'd highly recommend to introduce a Logging Framework and make log entries accordingly, so you may find the culprid.

c# set timeout for multipartReader.ReadNextSectionAsync()

I'm using C# .net core to read upload data from multipart post user sending multiple files.
How can I prevent use waiting infinite after read last file in
try
{
var cancellationTokenSource = new CancellationTokenSource();
cancellationTokenSource.CancelAfter(1000);
section = await multipartReader.ReadNextSectionAsync(cancellationTokenSource.Token);
}
catch (Exception ex)
{
throw;
}
Altough I've set cancelationToken for 1 second but it goes infinite, and won't go to
next line if I will send another request.
public static async Task<HttpRequest> FromHttpContextAsync(HttpContext httpContext)
{
bool multipart = false;
HttpRequest retVal = new HttpRequest(httpContext);
var sb = new StringBuilder();
var sr = new StreamReader(httpContext.Stream, Encoding.UTF8);
{
var line1 = await sr.ReadLineAsync();
sb.AppendLine(line1);
var Line1Parts = (line1).Split(' ');
retVal.Methode = Line1Parts[0].ToLower();
retVal.RawUrl = System.Net.WebUtility.UrlDecode(Line1Parts[1]).Replace("&", "&");
var urlPart = retVal.RawUrl.Split('?');
retVal.Url = urlPart[0];
if (urlPart.Length > 1)
{
foreach (var part in urlPart[1].Split(new[] { '&' }, StringSplitOptions.RemoveEmptyEntries))
{
var tmp = part.Split(new[] { '=' }, StringSplitOptions.RemoveEmptyEntries);
try
{
retVal.QueryStrings.Add(tmp[0], tmp[1]);
}
catch (Exception ex)
{
}
}
}
string line = await sr.ReadLineAsync();
sb.AppendLine(line);
int contentLength = 0;
while (!string.IsNullOrEmpty(line))
{
var tmp = line.Split(':');
var key = tmp[0].Trim().ToLower();
retVal.Header.Add(new KeyValuePair<string, string>(tmp[0], tmp[1]));
switch (key)
{
case "cookie":
{
foreach (var part in tmp[1].Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries))
{
var pares = part.Split('=');
if (pares.Length == 2)
{
retVal.Cookies.Add(new KeyValuePair<string, string>(pares[0], pares[1]));
}
}
break;
}
case "content-length":
{
contentLength = int.Parse(tmp[1]);
break;
}
}
line = await sr.ReadLineAsync();
sb.AppendLine(line);
}
if (sb.ToString().Contains("Content-Type: multipart/form-data"))
{
string boundary = FindBoundary(sb.ToString());
MultipartReader multipartReader = new MultipartReader(boundary, httpContext.Stream);
var section = await multipartReader.ReadNextSectionAsync();
while (section != null)
{
// process each image
const int chunkSize = 1024;
var buffer = new byte[chunkSize];
var bytesRead = 0;
var fileName = GetFileName(section.ContentDisposition);
using (var stream = new MemoryStream())
{
do
{
try
{
bytesRead = await section.Body.ReadAsync(buffer, 0, buffer.Length);
}
catch (Exception ex)
{
Console.Write(ex);
}
stream.Write(buffer, 0, bytesRead);
} while (bytesRead > 0);
retVal.Files.Add(new Tuple<string, string, byte[]>("", fileName, stream.ToArray()));
}
try
{
var cancellationTokenSource = new CancellationTokenSource();
cancellationTokenSource.CancelAfter(1000);
section = await multipartReader.ReadNextSectionAsync(cancellationTokenSource.Token);
}
catch (Exception ex)
{
throw;
}
}
foreach (var file in retVal.Files)
{
File.WriteAllBytes("d:\\" + file.Item2, file.Item3);
}
}
HttpContext is inline class of this project and this is the source of HttpContext :
public class HttpContext
{
public HttpRequest Request { get; private set; }
public HttpResponse Response { get; private set; }
public Stream Stream { private set; get; }
private HttpContext(Stream networkStream)
{
Stream = networkStream;
}
public async static Task<HttpContext> FromHttpContextAsync(Stream networkStream)
{
var retVal = new HttpContext(networkStream);
retVal.Request = await HttpRequest.FromHttpContextAsync(retVal);
retVal.Response = HttpResponse.FromHttpContext(retVal);
return retVal;
}
}

While the lack of details and context makes trying to reproduce this issue really hard, I suspect the problem here is due to the fact NetworkStreams (used, under the covers, by your MultipartReader instance) do not yet fully support CancellationTokens. In fact, almost every Socket-related operation on .NET Core just checks for the eventually passed CancellationToken upfront - which is useless, in my opinion.
The good news is that the .NET Core team is actively working on this and I believe the issue will be completely solved in .NET Core 3.0:
https://github.com/dotnet/corefx/issues/24430
As a temporary ugly workaround, you can change your code to wait for both a fabricated delay task and your call to ReadNextSectionAsync(), assuming you don't want to re-used that stalled socket / NetworkStream after that:
var timeoutTask = Task.Delay(TimeSpan.FromSeconds(1)).ConfigureAwait(false);
var readNextSectionTask = multipartReader.ReadNextSectionAsync().ConfigureAwait(false);
if (await Task.WhenAny(timeoutTask, readNextSectionTask).ConfigureAwait(false) == timeoutTask)
{
// TODO: Handle the timeout
}
else
{
section = await readNextSectionTask;
}
Additionally, the fact you are not configuring your awaitable may act as a possible deadlock source (it is unclear to me whether you are running this code on ASP.NET Core itself or on some other synchronization context provider). To exclude this possibility, I would suggest to call ConfigureAwait(false) right after your await calls, as you can see on my previous code block.

Update in couchbase

I need some help in update using couchbase. I have a task in my page. If the user clicks the like then the likes count should be updated in my couchbase bucket. I have tried my own update handler code but that has some time latency. I have included my update code too below.
This is my code for liking a task...
public ResponseVO LikeTask(LikeVO likeVO)
{
ResponseVO response = new ResponseVO();
try
{
if (!isLiked(likeVO.TaskID, likeVO.UserID))
{
UpdateTaskDB likeUpdate = new UpdateTaskDB();
UpdateTaskVO updatetaskvo = new UpdateTaskVO();
updatetaskvo.FieldName = "Likes";
LikeVO tempvo = new LikeVO();
tempvo.LikedOn = DateTime.Now.ToString();
tempvo.UserID = likeVO.UserID;
tempvo.UserName = likeVO.UserName;
tempvo.TaskID = likeVO.TaskID;
updatetaskvo.ObjectValue = tempvo;
updatetaskvo.TaskID = likeVO.TaskID;
likeUpdate.UpdateDocument(updatetaskvo);
}
response.StatusMessage = "Liked Successfully";
}
catch (Exception ex)
{
response.StatusCode = "0";
response.StatusMessage = ex.Message;
}
return response;
}
My own update handler code:
public class UpdateTaskDB
{
CouchbaseClient oCouchbase;
public UpdateTaskDB()
{
oCouchbase = new CouchbaseClient("vwspace", "");
}
public TaskVO GetTaskByID(string task_id)
{
TaskVO results = null;
try
{
String str1;
str1 = (String)oCouchbase.Get(task_id);
results = JsonConvert.DeserializeObject<TaskVO>(str1);
}
catch (Exception ex)
{
}
return results;
}
public void UpdateDocument(UpdateTaskVO inputParams)
{
try
{
var client = new CouchbaseClient("vwspace", "");
TaskVO taskDoc = GetTaskByID(inputParams.TaskID);
switch (inputParams.FieldName)
{
case "Likes":
List<LikeVO> docLikes = taskDoc.likes;
docLikes.Add((LikeVO)inputParams.ObjectValue);
taskDoc.likes = docLikes;
break;
case "UnLike":
LikeVO unlikevo = (LikeVO)inputParams.ObjectValue;
for (int count = 0; count < taskDoc.likes.Count; count++)
{
if (taskDoc.likes[count].UserID.Equals(unlikevo.UserID))
{
unlikevo = taskDoc.likes[count];
break;
}
}
taskDoc.likes.Remove(unlikevo);
break;
default:
break;
}
String json = JsonConvert.SerializeObject(taskDoc);
client.Store(StoreMode.Set, inputParams.TaskID, json);
}
catch (Exception ex)
{
Console.Write("Exception :" + ex.Message);
}
}
}
Is ther any other way to handle this update in couchbase? Kindly help me out..

The latency you're seeing is likely due to the fact that you're creating two instances of the CouchbaseClient for each click. Creating an instance of a CouchbaseClient is an expensive operation, because of the bootstrapping and configuration setup that takes place.
There are a couple of different approaches you can take to minimize how frequently you create CouchbaseClient instances. One would be to create a static client that is reused by your data access classes. Another approach for web apps is to associate instances with HttpApplication instances. For an example of the Web approach, see my (incomplete) sample project on GitHub below.
https://github.com/jzablocki/couchbase-beer.net/blob/master/src/CouchbaseBeersWeb/Models/WebRepositoryBase%271.cs
Also, I would suggest using CAS operations when updating a document's like count. You want to make sure that a "like" vote doesn't cause the entire document to be update from a stale read.
For example:
public TaskVO GetTaskByID(string task_id)
{
var getResult = oCouchbase.ExecuteGet<string>(task_id);
var results = JsonConvert.DeserializeObject<TaskVO>(str1.Value);
results.Cas = getResult.Cas; //Here I'm suggesting adding a Cas property to your TaskVO
return results;
}
Then on your update:
public void UpdateDocument(UpdateTaskVO inputParams)
{
try
{
TaskVO taskDoc = GetTaskByID(inputParams.TaskID);
switch (inputParams.FieldName)
{
...
}
String json = JsonConvert.SerializeObject(taskDoc);
client.ExecuteStore(StoreMode.Set, inputParams.TaskID, json, taskDoc.Cas);
//this will fail if the document has been updated by another user. You could use a retry strategy
}
catch (Exception ex)
{
Console.Write("Exception :" + ex.Message);
}
}