[Test-Proxy] Remove Explicit List of Content-Headers (#2914)

* remove explicit list of content headers
* adding tests to reflect logic updates of targeted content headers

Co-authored-by: JoshLove-msft <54595583+JoshLove-msft@users.noreply.github.com>

tools/test-proxy/Azure.Sdk.Tools.TestProxy.Tests/RecordingHandlerTests.cs

@@ -23,6 +23,34 @@ namespace Azure.Sdk.Tools.TestProxy.Tests
 {
     public class RecordingHandlerTests
     {
+        private HttpContext GenerateHttpRequestContext(string[] headerValueStrings)
+        {
+            HttpContext context = new DefaultHttpContext();
+
+            foreach(var hTuple in GenerateHeaderValuesTuples(headerValueStrings))
+            {
+
+                context.Request.Headers.TryAdd(hTuple.Item1, hTuple.Item2);
+            }
+
+            context.Request.Headers.TryAdd("x-recording-upstream-base-uri", new string[] { "https://hello-world" });
+            context.Request.Method = "POST";
+
+            return context;
+        }
+
+        private IEnumerable<Tuple<string, StringValues>> GenerateHeaderValuesTuples(string[] headerValueStrings) {
+            var returnedTuples = new List<Tuple<string, StringValues>>();
+            foreach (var headString in headerValueStrings)
+            {
+                var splitLocation = headString.IndexOf(':');
+                var headerKey = headString.Substring(0, splitLocation);
+                var headerValue = headString.Substring(splitLocation).Split(";").ToArray();
+                returnedTuples.Add(new Tuple<string, StringValues>(headerKey, headerValue));
+            }
+
+            return returnedTuples;
+        }
 
         private NullLoggerFactory _nullLogger = new NullLoggerFactory();
 
@@ -564,6 +592,45 @@ public async Task CreateEntryUsesAbsoluteUri()
             var entry = await RecordingHandler.CreateEntryAsync(request);
             Assert.Equal(uri.AbsoluteUri, entry.RequestUri);
         }
+
+
+        [Theory]
+        [InlineData("Content-Type:application/json; odata=minimalmetadata; streaming=true", "Accept:application/json;odata=minimalmetadata")]
+        [InlineData("Content-MD5:<ContentHash>", "x-ms-version:2019-02-02", "RequestMethod:POST", "Connection:keep-alive")]
+        [InlineData("Content-Encoding:utf-8", "x-ms-version:2019-02-02", "RequestMethod:POST", "Content-Length:50")]
+        public void TestCreateUpstreamRequestIncludesExpectedHeaders(params string[] incomingHeaders)
+        {
+            var requestContext = GenerateHttpRequestContext(incomingHeaders);
+            var recordingHandler = new RecordingHandler(Directory.GetCurrentDirectory());
+            var upstreamRequestContext = GenerateHttpRequestContext(incomingHeaders);
+
+            var output = recordingHandler.CreateUpstreamRequest(upstreamRequestContext.Request, new byte[] { });
+
+            // iterate across the set we know about and confirm that GenerateUpstreamRequest worked properly!
+            var setOfHeaders = GenerateHeaderValuesTuples(incomingHeaders);
+            {
+                foreach (var headerTuple in setOfHeaders)
+                {
+                    var inContent = false;
+                    var inStandard = false;
+
+                    try
+                    {
+                        inContent = output.Headers.Contains(headerTuple.Item1);
+                    }
+                    catch (Exception) { }
+
+                    try
+                    {
+                        inStandard = output.Content.Headers.Contains(headerTuple.Item1);
+                    }
+                    catch (Exception) { }
+
+                    Assert.True(inContent || inStandard);
+                }
+            }
+        }
+
     }
 
     internal class MockHttpHandler : HttpMessageHandler

tools/test-proxy/Azure.Sdk.Tools.TestProxy/RecordingHandler.cs

@@ -46,12 +46,6 @@ public RecordingHandler(string targetDirectory)
             "Proxy-Connection",
         };
 
-        // Headers which must be set on HttpContent instead of HttpRequestMessage
-        private static readonly string[] s_contentRequestHeaders = new string[] {
-            "Content-Length",
-            "Content-Type",
-        };
-
         public List<RecordedTestSanitizer> Sanitizers { get; set; }
 
         public List<ResponseTransform> Transforms { get; set; }
@@ -265,7 +259,7 @@ private byte[] DecompressBody(MemoryStream incomingBody, HttpContentHeaders head
             return incomingBody.ToArray();
         }
 
-        private HttpRequestMessage CreateUpstreamRequest(HttpRequest incomingRequest, byte[] incomingBody)
+        public HttpRequestMessage CreateUpstreamRequest(HttpRequest incomingRequest, byte[] incomingBody)
         {
             var upstreamRequest = new HttpRequestMessage();
             upstreamRequest.RequestUri = GetRequestUri(incomingRequest);
@@ -276,29 +270,27 @@ private HttpRequestMessage CreateUpstreamRequest(HttpRequest incomingRequest, by
             {
                 IEnumerable<string> values = header.Value;
 
+                // can't handle PROXY_CONNECTION right now.
                 if (s_excludedRequestHeaders.Contains(header.Key, StringComparer.OrdinalIgnoreCase))
                 {
                     continue;
                 }
 
-                try
+                if (!header.Key.StartsWith("x-recording"))
                 {
-                    if (s_contentRequestHeaders.Contains(header.Key, StringComparer.OrdinalIgnoreCase))
+                    if (upstreamRequest.Headers.TryAddWithoutValidation(header.Key, values))
                     {
-                        upstreamRequest.Content.Headers.TryAddWithoutValidation(header.Key, values);
+                        continue;
                     }
-                    else
+
+                    if(!upstreamRequest.Content.Headers.TryAddWithoutValidation(header.Key, values))
                     {
-                        if (!header.Key.StartsWith("x-recording"))
-                        {
-                            upstreamRequest.Headers.TryAddWithoutValidation(header.Key, values);
-                        }
+                        throw new HttpException(
+                            HttpStatusCode.BadRequest,
+                            $"Encountered an unexpected exception while mapping a content header during upstreamRequest creation. Header: \"{header.Key}\". Value: \"{String.Join(",", values)}\""
+                        );
                     }
                 }
-                catch (Exception)
-                {
-                    // ignore
-                }
             }
 
             upstreamRequest.Headers.Host = upstreamRequest.RequestUri.Host;