fix: Do not dispose a custom HTTP message handler in an HTTP wait strategy (#958)

Author: jacobjmarks

src/Testcontainers/Configurations/WaitStrategies/HttpWaitStrategy.cs

@@ -66,7 +66,7 @@ public async Task<bool> UntilAsync(IContainer container)
         return false;
       }
 
-      using (var httpClient = new HttpClient(_httpMessageHandler ?? new HttpClientHandler()))
+      using (var httpClient = new HttpClient(_httpMessageHandler ?? new HttpClientHandler(), disposeHandler: _httpMessageHandler == null))
       {
         using (var httpRequestMessage = new HttpRequestMessage(_httpMethod, new UriBuilder(_schemeName, host, port, _pathValue).Uri))
         {
@@ -82,7 +82,7 @@ public async Task<bool> UntilAsync(IContainer container)
             httpResponseMessage = await httpClient.SendAsync(httpRequestMessage)
               .ConfigureAwait(false);
           }
-          catch
+          catch (HttpRequestException)
           {
             return false;
           }

tests/Testcontainers.Tests/Unit/Configurations/WaitUntilHttpRequestIsSucceededTest.cs

@@ -19,7 +19,7 @@ public sealed class WaitUntilHttpRequestIsSucceededTest : IAsyncLifetime
     private readonly IContainer _container = new ContainerBuilder()
       .WithImage(CommonImages.Alpine)
       .WithEntrypoint("/bin/sh", "-c")
-      .WithCommand($"echo \"HTTP/1.1 200 OK\r\n\" | nc -l -p {HttpPort}")
+      .WithCommand($"while true; do echo \"HTTP/1.1 200 OK\r\n\" | nc -l -p {HttpPort}; done")
       .WithPortBinding(HttpPort, true)
       .Build();
 
@@ -110,5 +110,22 @@ await Task.Delay(TimeSpan.FromSeconds(1))
       Assert.Contains("Cookie", stdout);
       Assert.Contains("Key1=Value1", stdout);
     }
+
+    [Fact]
+    public async Task HttpWaitStrategyCanReuseCustomHttpClientHandler()
+    {
+      // Given
+      var httpWaitStrategy = new HttpWaitStrategy().UsingHttpMessageHandler(new HttpClientHandler());
+
+      // When
+      await httpWaitStrategy.UntilAsync(_container)
+        .ConfigureAwait(false);
+
+      var exceptionOnSubsequentCall = await Record.ExceptionAsync(() => httpWaitStrategy.UntilAsync(_container))
+        .ConfigureAwait(false);
+
+      // Then
+      Assert.Null(exceptionOnSubsequentCall);
+    }
   }
 }