Cache trimmed keys for @ and $

Author: sungam3r

src/Serilog.Extensions.Logging/Extensions/Logging/SerilogLogger.cs

@@ -10,11 +10,15 @@
 using FrameworkLogger = Microsoft.Extensions.Logging.ILogger;
 using System.Reflection;
 using Serilog.Debugging;
+using System.Collections.Concurrent;
 
 namespace Serilog.Extensions.Logging
 {
     class SerilogLogger : FrameworkLogger
     {
+        internal static readonly ConcurrentDictionary<string, string> DestructureDictionary = new ConcurrentDictionary<string, string>();
+        internal static readonly ConcurrentDictionary<string, string> StringifyDictionary = new ConcurrentDictionary<string, string>();
+
         readonly SerilogLoggerProvider _provider;
         readonly ILogger _logger;
 
@@ -91,12 +95,12 @@ void Write<TState>(LogEventLevel level, EventId eventId, TState state, Exception
                     }
                     else if (property.Key.StartsWith("@"))
                     {
-                        if (logger.BindProperty(property.Key.Substring(1), property.Value, true, out var destructured))
+                        if (logger.BindProperty(DestructureDictionary.GetOrAdd(property.Key, k => k.Substring(1)), property.Value, true, out var destructured))
                             properties.Add(destructured);
                     }
                     else if (property.Key.StartsWith("$"))
                     {
-                        if (logger.BindProperty(property.Key.Substring(1), property.Value?.ToString(), true, out var stringified))
+                        if (logger.BindProperty(StringifyDictionary.GetOrAdd(property.Key, k => k.Substring(1)), property.Value?.ToString(), true, out var stringified))
                             properties.Add(stringified);
                     }
                     else

src/Serilog.Extensions.Logging/Extensions/Logging/SerilogLoggerScope.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using Serilog.Core;
 using Serilog.Events;
@@ -59,13 +60,12 @@ void AddProperty(KeyValuePair<string, object> stateProperty)
 
                 if (key.StartsWith("@"))
                 {
-                    key = key.Substring(1);
+                    key = SerilogLogger.DestructureDictionary.GetOrAdd(key, k => k.Substring(1));
                     destructureObject = true;
                 }
-
-                if (key.StartsWith("$"))
+                else if (key.StartsWith("$"))
                 {
-                    key = key.Substring(1);
+                    key = SerilogLogger.StringifyDictionary.GetOrAdd(key, k => k.Substring(1));
                     value = value?.ToString();
                 }
 

test/Serilog.Extensions.Logging.Benchmarks/LogEventBenchmark.cs

@@ -0,0 +1,63 @@
+// Copyright 2019 Serilog Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Running;
+using Microsoft.Extensions.Logging;
+using Xunit;
+using IMelLogger = Microsoft.Extensions.Logging.ILogger;
+
+namespace Serilog.Extensions.Logging.Benchmarks
+{
+    [MemoryDiagnoser]
+    public class LogEventBenchmark
+    {
+        private class Person
+        {
+            public string Name { get; set; }
+            public int Age { get; set; }
+            public override string ToString() => "Fixed text";
+        }
+
+        readonly IMelLogger _melLogger;
+        readonly Person _bob, _alice;
+
+        public LogEventBenchmark()
+        {
+            var underlyingLogger = new LoggerConfiguration().CreateLogger();
+            _melLogger = new SerilogLoggerProvider(underlyingLogger).CreateLogger(GetType().FullName);
+            _bob = new Person { Name = "Bob", Age = 42 };
+            _alice = new Person { Name = "Alice", Age = 42 };
+        }
+
+        [Fact]
+        public void Benchmark()
+        {
+            BenchmarkRunner.Run<LogEventBenchmark>();
+        }
+
+        [Benchmark]
+        public void LogInformation()
+        {
+            _melLogger.LogInformation("Hi {@User} from {$Me}", _bob, _alice);
+        }
+
+        [Benchmark]
+        public void LogInformationScoped()
+        {
+            using (var scope = _melLogger.BeginScope("Hi {@User} from {$Me}", _bob, _alice))
+                _melLogger.LogInformation("Hi");
+        }
+    }
+}