Fix cross appdomain exception

src/Microsoft.AspNetCore.Diagnostics.Elm/ElmScope.cs

@@ -26,7 +26,7 @@ namespace Microsoft.AspNetCore.Diagnostics.Elm
         public ScopeNode Node { get; set; }
 
 #if NET451
-        private static string FieldKey = typeof(ElmScope).FullName + ".Value";
+        private static readonly string FieldKey = $"{typeof(ElmScope).FullName}.Value.{AppDomain.CurrentDomain.Id}";
         public static ElmScope Current
         {
             get

src/Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore/DataStoreErrorLogger.cs

@@ -9,6 +9,7 @@ using System;
 #if NETSTANDARD1_3
 using System.Threading;
 #else
+using System.Runtime.Remoting;
 using System.Runtime.Remoting.Messaging;
 #endif
 
@@ -19,7 +20,7 @@ namespace Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore
 #if NETSTANDARD1_3
         private readonly AsyncLocal<DataStoreErrorLog> _log = new AsyncLocal<DataStoreErrorLog>(); 
 #else
-        private const string ContextName = "__DataStoreErrorLog";
+        private static readonly string ContextName = "__DataStoreErrorLog" + AppDomain.CurrentDomain.Id;
 #endif
 
         public virtual DataStoreErrorLog LastError
@@ -29,7 +30,9 @@ namespace Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore
 #if NETSTANDARD1_3
                 return _log.Value; 
 #else
-                return (DataStoreErrorLog)CallContext.LogicalGetData(ContextName);
+                var handle = CallContext.LogicalGetData(ContextName) as ObjectHandle;
+
+                return handle?.Unwrap() as DataStoreErrorLog;
 #endif
             }
         }
@@ -44,7 +47,7 @@ namespace Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore
 #if NETSTANDARD1_3
             _log.Value = new DataStoreErrorLog();
 #else
-            CallContext.LogicalSetData(ContextName, new DataStoreErrorLog());
+            CallContext.LogicalSetData(ContextName, new ObjectHandle(new DataStoreErrorLog()));
 #endif
         }
 

test/Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.Tests/DataStoreErrorLoggerTest.cs

@@ -0,0 +1,46 @@
+using System;
+using Microsoft.Extensions.Logging;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.Tests
+{
+#if NET451
+    public class DataStoreErrorLoggerTest
+    {
+        private const string _name = "test";
+
+        private static DataStoreErrorLogger SetUp(Func<string, LogLevel, bool> filter = null, string name = null)
+        {
+            // Arrange
+            var provider = new DataStoreErrorLoggerProvider();
+            var logger = (DataStoreErrorLogger)provider.CreateLogger(name ?? _name);
+
+            return logger;
+        }
+
+        private static void DomainFunc()
+        {
+            var logger = SetUp();
+            logger.StartLoggingForCurrentCallContext();
+            logger.LogInformation(0, "Test");
+        }
+
+        [Fact]
+        public void ScopeWithChangingAppDomains_DoesNotAccessUnloadedAppDomain()
+        {
+            // Arrange
+            var logger = SetUp();
+            var domain = AppDomain.CreateDomain("newDomain");
+
+            // Act
+            logger.StartLoggingForCurrentCallContext();
+            domain.DoCallBack(DomainFunc);
+            AppDomain.Unload(domain);
+            logger.LogInformation(0, "Testing");
+
+            // Assert
+            Assert.NotNull(logger.LastError);
+        }
+    }
+#endif
+}

test/Microsoft.AspNetCore.Diagnostics.Tests/ElmLoggerTest.cs

@@ -16,9 +16,9 @@ namespace Microsoft.AspNetCore.Diagnostics.Tests
     {
         private const string _name = "test";
         private const string _state = "This is a test";
-        private Func<string, LogLevel, bool> _filter = (_, __) => true;
+        private static Func<string, LogLevel, bool> _filter = (_, __) => true;
 
-        private Tuple<ElmLogger, ElmStore> SetUp(Func<string, LogLevel, bool> filter = null, string name = null)
+        private static Tuple<ElmLogger, ElmStore> SetUp(Func<string, LogLevel, bool> filter = null, string name = null)
         {
             // Arrange
             var store = new ElmStore();
@@ -305,6 +305,37 @@ namespace Microsoft.AspNetCore.Diagnostics.Tests
             Assert.Empty(store.GetActivities());
         }
 
+#if NET451
+        private static void DomainFunc()
+        {
+            var t = SetUp();
+            var logger = t.Item1;
+            using (logger.BeginScope("newDomain scope"))
+            {
+                logger.LogInformation("Test");
+            }
+        }
+
+        [Fact]
+        public void ScopeWithChangingAppDomains_DoesNotAccessUnloadedAppDomain()
+        {
+            // Arrange
+            var t = SetUp();
+            var logger = t.Item1;
+            var store = t.Item2;
+            var domain = AppDomain.CreateDomain("newDomain");
+
+            // Act
+            domain.DoCallBack(DomainFunc);
+            AppDomain.Unload(domain);
+            using (logger.BeginScope("Scope1"))
+            {
+                logger.LogInformation("Testing");
+            }
+
+            Assert.Equal(1, store.Count());
+        }
+#endif
 
         private List<LogInfo> NodeLogs(ScopeNode node, List<LogInfo> logs)
         {