Tweak the test to retry up to 5 times and dump the retrieved content

Author: grendello

tests/Mono.Android-Tests/Xamarin.Android.Net/AndroidMessageHandlerTests.cs

@@ -39,7 +39,20 @@ protected override HttpMessageHandler CreateHandler ()
 #if NET
 		[Test]
 		[TestCaseSource (nameof (DecompressionSource))]
+		[Retry (5)]
 		public async Task Decompression (string urlPath, string encoding, string jsonFieldName)
+		{
+			// Catch all the exceptions and warn about them or otherwise [Retry] above won't work
+			try {
+				DoDecompression (urlPath, encoding, jsonFieldName);
+			} catch (Exception ex) {
+				Assert.Warn ("Unexpected exception thrown");
+				Assert.Warn (ex.ToString ());
+				Assert.Fail ("Exception should have not been thrown");
+			}
+		}
+
+		void DoDecompression (string urlPath, string encoding, string jsonFieldName)
 		{
 			var handler = new AndroidMessageHandler {
 				AutomaticDecompression = DecompressionMethods.All
@@ -48,6 +61,14 @@ public async Task Decompression (string urlPath, string encoding, string jsonFie
 			var client = new HttpClient (handler);
 			HttpResponseMessage response = await client.GetAsync ($"https://httpbin.org/{urlPath}");
 
+			// Failing on error codes other than 2xx will make NUnit retry the test up to the number of times specified in the
+			// [Retry] attribute above.  This may or may not the desired effect if httpbin.org is throttling the requests, thus
+			// we will sleep a short while before failing the test
+			if (!response.IsSuccessStatusCode) {
+				System.Threading.Thread.Sleep (1000);
+				Assert.Fail ($"Request ended with a failure error code: {response.StatusCode}");
+			}
+
 			foreach (string enc in response.Content.Headers.ContentEncoding) {
 				if (String.Compare (enc, encoding, StringComparison.Ordinal) == 0) {
 					Assert.Fail ($"Encoding '{encoding}' should have been removed from the Content-Encoding header");
@@ -56,6 +77,10 @@ public async Task Decompression (string urlPath, string encoding, string jsonFie
 
 			string responseBody = await response.Content.ReadAsStringAsync ();
 
+			Assert.Warn ("-- Retrieved JSON start");
+			Assert.Warn (responseBody);
+			Assert.Warn ("-- Retrieved JSON end");
+
 			Assert.IsTrue (responseBody.Length > 0, "Response was empty");
 			Assert.AreEqual (response.Content.Headers.ContentLength, responseBody.Length, "Retrieved data length is different than the one specified in the Content-Length header");
 			Assert.IsTrue (responseBody.Contains ($"\"{jsonFieldName}\"", StringComparison.OrdinalIgnoreCase), $"\"{jsonFieldName}\" should have been in the response JSON");