Remove the WithCancellation

Check cancellation before action

Author: Duracell1989

src/Docker.DotNet/Endpoints/StreamUtil.cs

@@ -1,10 +1,10 @@
+using Newtonsoft.Json;
 using System;
 using System.IO;
 using System.Net.Http;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
-using Newtonsoft.Json;
 
 namespace Docker.DotNet.Models
 {
@@ -20,7 +20,7 @@ internal static async Task MonitorStreamAsync(Task<Stream> streamTask, DockerCli
                 using (var reader = new StreamReader(stream, new UTF8Encoding(false)))
                 {
                     string line;
-                    while ((line = await reader.ReadLineAsync()) != null && !cancel.IsCancellationRequested)
+                    while (!cancel.IsCancellationRequested && (line = await reader.ReadLineAsync()) != null)
                     {
                         progress.Report(line);
                     }
@@ -34,7 +34,7 @@ internal static async Task MonitorStreamForMessagesAsync<T>(Task<Stream> streamT
             using (var reader = new StreamReader(stream, new UTF8Encoding(false)))
             using (var jsonReader = new JsonTextReader(reader) { SupportMultipleContent = true })
             {
-                while (await jsonReader.ReadAsync().WithCancellation(cancel))
+                while (!cancel.IsCancellationRequested && await jsonReader.ReadAsync())
                 {
                     var ev = _serializer.Deserialize<T>(jsonReader);
                     progress?.Report(ev);
@@ -56,7 +56,7 @@ internal static async Task MonitorResponseForMessagesAsync<T>(Task<HttpResponseM
                         string line;
                         try
                         {
-                            while ((line = await reader.ReadLineAsync()) != null && !cancel.IsCancellationRequested)
+                            while (!cancel.IsCancellationRequested && (line = await reader.ReadLineAsync()) != null)
                             {
                                 var prog = client.JsonSerializer.DeserializeObject<T>(line);
                                 if (prog == null) continue;
@@ -73,19 +73,5 @@ internal static async Task MonitorResponseForMessagesAsync<T>(Task<HttpResponseM
                 }
             }
         }
-
-        private static async Task<T> WithCancellation<T>(this Task<T> task, CancellationToken cancellationToken)
-        {
-            var tcs = new TaskCompletionSource<bool>();
-            using (cancellationToken.Register(s => ((TaskCompletionSource<bool>)s).TrySetResult(true), tcs))
-            {
-                if (task != await Task.WhenAny(task, tcs.Task))
-                {
-                    throw new OperationCanceledException(cancellationToken);
-                }
-            }
-
-            return await task;
-        }
     }
 }