mono · lewing · Jun 18, 2019 · Jun 12, 2019 · Jun 12, 2019 · Jun 17, 2019
diff --git a/sdks/wasm/framework/src/WebAssembly.Net.Http/WasmHttpMessageHandler.cs b/sdks/wasm/framework/src/WebAssembly.Net.Http/WasmHttpMessageHandler.cs
@@ -176,29 +176,29 @@ private async Task doFetch (TaskCompletionSource<HttpResponseMessage> tcs, HttpR
 				// View more information https://developers.google.com/web/updates/2015/03/introduction-to-fetch#response_types
 				//
 				// Note: Some of the headers may not even be valid header types in .NET thus we use TryAddWithoutValidation
-				using (var respHeaders = status.Headers) {
-					// Here we invoke the forEach on the headers object
-					// Note: the Action takes 3 objects and not two.  The other seems to be the Header object.
-					var foreachAction = new Action<object, object, object> ((value, name, other) => {
-
-						if (!httpresponse.Headers.TryAddWithoutValidation ((string)name, (string)value))
-							if (httpresponse.Content != null)
-								if (!httpresponse.Content.Headers.TryAddWithoutValidation ((string)name, (string)value))
-									Console.WriteLine ($"Warning: Can not add response header for name: {name} value: {value}");
-						((JSObject)other).Dispose ();
-					});
-
-					try {
-
-						respHeaders.Invoke ("forEach", foreachAction);
-					} finally {
-						// Do not remove the following line of code.  The httpresponse is used in the lambda above when parsing the Headers.
-						// if a local is captured (used) by a lambda it becomes heap memory as we translate them into fields on an object.
-						// The foreachAction is allocated when marshalled to JavaScript.  Since we do not know when JS is finished with the
-						// Action we need to tell the Runtime to de-allocate the object and remove the instance from JS as well.
-						WebAssembly.Runtime.FreeObject (foreachAction);
+				using (var respHeaders = (JSObject)status.Headers) {
+					if (respHeaders != null) {
+						using (var entriesIterator = (JSObject)respHeaders.Invoke ("entries")) {
+							JSObject nextResult = null;
+							try {
+								nextResult = (JSObject)entriesIterator.Invoke ("next");
+								while (!(bool)nextResult.GetObjectProperty ("done")) {
+									using (var resultValue = (WebAssembly.Core.Array)nextResult.GetObjectProperty ("value")) {
+										var name = (string)resultValue [0];
+										var value = (string)resultValue [1];
+										if (!httpresponse.Headers.TryAddWithoutValidation (name, value))
+											if (httpresponse.Content != null)
+												if (!httpresponse.Content.Headers.TryAddWithoutValidation (name, value))
+													Console.WriteLine ($"Warning: Can not add response header for name: {name} value: {value}");
+									}
+									nextResult?.Dispose ();
+									nextResult = (JSObject)entriesIterator.Invoke ("next");
+								}
+							} finally {
+								nextResult?.Dispose ();
+							}
+						}
 					}
-
 				}
 
 				tcs.SetResult (httpresponse);
@@ -433,7 +433,6 @@ public override void Write (byte [] buffer, int offset, int count)
 				throw new NotSupportedException ();
 			}
 		}
-
 	}
 
 	/// <summary>
@@ -535,5 +534,5 @@ public enum RequestMode {
 		[Export (EnumValue = ConvertEnum.ToLower)]
 		Navigate,
 	}
-
+	
 }
diff --git a/sdks/wasm/tests/browser/IssuesTestSuite.cs b/sdks/wasm/tests/browser/IssuesTestSuite.cs
@@ -4,6 +4,7 @@
 using System.ComponentModel;
 using System.Reflection;
 using System.Runtime.InteropServices;
+using System.Net.Http;
 using WebAssembly;
 using WebAssembly.Core;
 
@@ -43,6 +44,61 @@ public static double Issue13428()
             var k = Math.Truncate(20d); // a print window pops up
             return k;        
         }
+
+        static WebAssembly.Core.Array fetchResponse = new WebAssembly.Core.Array();
+        public static async Task<object> IssueDoubleFetch ()
+        {
+            await Fetch();
+            await Fetch();
+            return fetchResponse;
+        } 
+
+        private static async Task Fetch()
+        {
+            var client = CreateHttpClient();
+            var response = await client.GetStringAsync("base/publish/NowIsTheTime.txt");
+            fetchResponse.Push(response);
+        }   
+
+        static WebAssembly.Core.Array fetchHeadersResponse = new WebAssembly.Core.Array();
+        public static async Task<object> IssueDoubleFetchHeaders ()
+        {
+
+            await FetchHeaders();
+            await FetchHeaders();
+            return fetchHeadersResponse;
+        } 
+
+        private static async Task FetchHeaders()
+        {
+            var client = CreateHttpClient();
+            var response = await client.GetAsync("base/publish/NowIsTheTime.txt");
+            // Raise exception if fails
+            response.EnsureSuccessStatusCode();
+            // On success, return sign in results from the server response packet
+            var responseContent = await response.Content.ReadAsStringAsync();
+            fetchHeadersResponse.Push(response.Headers.ToString());
+        }   
+
+        static HttpClient CreateHttpClient()
+        {
+            //Console.WriteLine("Create  HttpClient");
+            string BaseApiUrl = string.Empty;
+            var window = (JSObject)WebAssembly.Runtime.GetGlobalObject("window");
+            using (var location = (JSObject)window.GetObjectProperty("location"))
+            {
+                BaseApiUrl = (string)location.GetObjectProperty("origin");
+            }
+            // WasmHttpMessageHandler.StreamingEnabled = true;
+            //                 var client = new System.Net.Http.HttpClient()
+            //     {
+            //         DefaultRequestHeaders = { { "origin", "WindowsCalculator" } }
+            //     };
+
+            return new HttpClient() { BaseAddress = new Uri(BaseApiUrl), DefaultRequestHeaders = { { "origin", "WindowsCalculator" } } };
+        }
+
+
     }
 
     [Flags]
@@ -177,4 +233,5 @@ public enum Longs : long
         [Description("64 bits")]
         enum64 = unchecked((long)0x8000000000000000L)
     }
+
 }
diff --git a/sdks/wasm/tests/browser/issues-spec.js b/sdks/wasm/tests/browser/issues-spec.js
@@ -58,4 +58,41 @@ describe("The WebAssembly Issues Test Suite",function(){
       assert.equal(doublevalue, 20, "result doesn't match 20");
 
     }, DEFAULT_TIMEOUT);  
+
+    it('IssuesTestSuite: https://github.com/mono/mono/issues/14940 should not crash when issuing two fetchs back to back.', (done) => {
+      //karmaHTML.issuesspec.document gives the access to the Document object of 'http-spec.html' file
+      var _document = karmaHTML.issuesspec.document;
+      _document.Module.BINDING.call_static_method("[IssuesTestSuite]TestSuite.Program:IssueDoubleFetch", []).then(
+        (result) => 
+        {
+            try {
+              assert.equal(result.length, 2, "result does not match Fetch Issue of 2.");
+              done()
+            } catch (e) {
+              done.fail(e);
+            }
+        },
+        (error) => done.fail(error)
+
+      );
+    }, DEFAULT_TIMEOUT);  
+
+    it('IssuesTestSuite: https://github.com/mono/mono/issues/14940 should not crash when retrieving headers issuing two fetchs back to back.', (done) => {
+      //karmaHTML.issuesspec.document gives the access to the Document object of 'http-spec.html' file
+      var _document = karmaHTML.issuesspec.document;
+      _document.Module.BINDING.call_static_method("[IssuesTestSuite]TestSuite.Program:IssueDoubleFetchHeaders", []).then(
+        (result) => 
+        {
+            try {
+              assert.equal(result.length, 2, "result does not match number of headers 2.");
+              done()
+            } catch (e) {
+              done.fail(e);
+            }
+        },
+        (error) => done.fail(error)
+
+      );
+    }, DEFAULT_TIMEOUT);  
+
   });