Update RELEASE_NOTES.md for 1.5.57-beta2 release

RELEASE_NOTES.md

@@ -1,3 +1,17 @@
+#### 1.5.57-beta2 December 3rd 2025 ####
+
+* [Update Akka.NET to 1.5.57-beta2](https://github.com/akkadotnet/akka.net/releases/tag/1.5.57-beta2)
+* [Add semantic logging support for Akka.NET 1.5.56+](https://github.com/akkadotnet/Akka.Logger.Serilog/pull/294)
+
+This release adds full semantic logging support, enabling Serilog to receive properly structured message templates and parameters instead of pre-formatted strings. This enhancement leverages Akka.NET's semantic logging APIs introduced in version 1.5.56, enabling richer structured logging capabilities.
+
+**New Features:**
+- **Semantic Logging**: Serilog now receives message templates with named and positional parameters for true structured logging
+- **Enhanced Template Support**: Full support for Serilog destructuring (`@`), stringification (`$`), and format specifiers (e.g., `:N2`)
+- **ForContext Integration**: Semantic logging works seamlessly with `ForContext()` for enriched log contexts
+- **Akka Metadata Preservation**: All Akka.NET metadata (timestamp, log level, thread, logger name) is preserved in structured logs
+- **Backwards Compatible**: Fully compatible with older Akka.NET versions through `LogMessage` type checking
+
 #### 1.5.25 June 17 2024 ####
 
 * [Update Akka.Hosting to 1.5.25](https://github.com/akkadotnet/akka.net/releases/tag/1.5.25)

src/Akka.Logger.Serilog.Tests/SerilogFormattingSpecs.cs

@@ -11,6 +11,7 @@
 using Serilog;
 using Xunit;
 using Xunit.Abstractions;
+using LogEvent = Serilog.Events.LogEvent;
 using SerilogLog = Serilog.Log;
 
 namespace Akka.Logger.Serilog.Tests
@@ -53,10 +54,11 @@ public async Task RawLogOutputRegressionTest(string version, string expected, st
             await AwaitConditionAsync(() => _sink.Writes.Count == 0);
 
             _serilogLogger.Information(messageFormat, args);
-            await AwaitConditionAsync(() => _sink.Writes.Count == 1);
 
-            _sink.Writes.TryDequeue(out var logEvent).Should().BeTrue();
-            logEvent!.RenderMessage().Should().Be(expected);
+            await AwaitConditionAsync(() => AssertCondition(logEvent =>
+            {
+                logEvent.RenderMessage().Should().Be(expected);
+            }));
         }
 
         [Theory(DisplayName = "SerilogLoggingAdapter output must be compatible with previous version")]
@@ -67,10 +69,11 @@ public async Task AdapterLogOutputRegressionTest(string version, string expected
             await AwaitConditionAsync(() => _sink.Writes.Count == 0);
 
             _loggingAdapter.Info(messageFormat, args);
-            await AwaitConditionAsync(() => _sink.Writes.Count == 1);
 
-            _sink.Writes.TryDequeue(out var logEvent).Should().BeTrue();
-            logEvent!.RenderMessage().Should().Contain(expected);
+            await AwaitConditionAsync(() => AssertCondition(logEvent =>
+            {
+                logEvent.RenderMessage().Should().Contain(expected);
+            }));
         }
 
         [Theory(DisplayName = "Default ILoggingAdapter output must be compatible with previous version")]
@@ -81,10 +84,28 @@ public async Task LogOutputRegressionTest(string version, string expected, strin
             await AwaitConditionAsync(() => _sink.Writes.Count == 0);
 
             Sys.Log.Info(messageFormat, args);
-            await AwaitConditionAsync(() => _sink.Writes.Count == 1);
 
-            _sink.Writes.TryDequeue(out var logEvent).Should().BeTrue();
-            logEvent!.RenderMessage().Should().Contain(expected);
+            await AwaitConditionAsync(() => AssertCondition(logEvent =>
+            {
+                logEvent.RenderMessage().Should().Contain(expected);
+            }));
+        }
+
+        private bool AssertCondition(Action<LogEvent> assertion)
+        {
+            while (_sink.Writes.TryDequeue(out var logEvent))
+            {
+                try
+                {
+                    assertion(logEvent);
+                    return true;
+                }
+                catch
+                {
+                    // no-op
+                }
+            }
+            return false;
         }
 
         [Theory]
@@ -93,13 +114,13 @@ public async Task LogOutputRegressionTest(string version, string expected, strin
         [InlineData(LogLevel.DebugLevel, "test case {myNum} {myStr}", new object[] { 1, "foo" })]
         public void ShouldHandleSerilogFormats(LogLevel level, string formatStr, object[] args)
         {
-            Sys.EventStream.Subscribe(TestActor, typeof(LogEvent));
+            Sys.EventStream.Subscribe(TestActor, typeof(Akka.Event.LogEvent));
 
             Action logWrite = () =>
             {
                 _loggingAdapter.Log(level, formatStr, args);
 
-                var logEvent = ExpectMsg<LogEvent>();
+                var logEvent = ExpectMsg<Akka.Event.LogEvent>();
                 logEvent.LogLevel().Should().Be(level);
                 logEvent.ToString().Should().NotBeEmpty();
             };