Trigger state buffering by processor inspection.

src/OpenTelemetry/.publicApi/net462/PublicAPI.Shipped.txt

@@ -46,8 +46,8 @@ OpenTelemetry.BatchExportProcessorOptions<T>.ScheduledDelayMilliseconds.set -> v
 OpenTelemetry.BatchLogRecordExportProcessor
 OpenTelemetry.BatchLogRecordExportProcessor.BatchLogRecordExportProcessor(OpenTelemetry.BaseExporter<OpenTelemetry.Logs.LogRecord!>! exporter, int maxQueueSize = 2048, int scheduledDelayMilliseconds = 5000, int exporterTimeoutMilliseconds = 30000, int maxExportBatchSize = 512) -> void
 OpenTelemetry.CompositeProcessor<T>
-~OpenTelemetry.CompositeProcessor<T>.AddProcessor(OpenTelemetry.BaseProcessor<T> processor) -> OpenTelemetry.CompositeProcessor<T>
-~OpenTelemetry.CompositeProcessor<T>.CompositeProcessor(System.Collections.Generic.IEnumerable<OpenTelemetry.BaseProcessor<T>> processors) -> void
+OpenTelemetry.CompositeProcessor<T>.AddProcessor(OpenTelemetry.BaseProcessor<T>! processor) -> OpenTelemetry.CompositeProcessor<T>!
+OpenTelemetry.CompositeProcessor<T>.CompositeProcessor(System.Collections.Generic.IEnumerable<OpenTelemetry.BaseProcessor<T>!>! processors) -> void
 OpenTelemetry.ExportProcessorType
 OpenTelemetry.ExportProcessorType.Batch = 1 -> OpenTelemetry.ExportProcessorType
 OpenTelemetry.ExportProcessorType.Simple = 0 -> OpenTelemetry.ExportProcessorType

src/OpenTelemetry/.publicApi/netstandard2.0/PublicAPI.Shipped.txt

@@ -46,8 +46,8 @@ OpenTelemetry.BatchExportProcessorOptions<T>.ScheduledDelayMilliseconds.set -> v
 OpenTelemetry.BatchLogRecordExportProcessor
 OpenTelemetry.BatchLogRecordExportProcessor.BatchLogRecordExportProcessor(OpenTelemetry.BaseExporter<OpenTelemetry.Logs.LogRecord!>! exporter, int maxQueueSize = 2048, int scheduledDelayMilliseconds = 5000, int exporterTimeoutMilliseconds = 30000, int maxExportBatchSize = 512) -> void
 OpenTelemetry.CompositeProcessor<T>
-~OpenTelemetry.CompositeProcessor<T>.AddProcessor(OpenTelemetry.BaseProcessor<T> processor) -> OpenTelemetry.CompositeProcessor<T>
-~OpenTelemetry.CompositeProcessor<T>.CompositeProcessor(System.Collections.Generic.IEnumerable<OpenTelemetry.BaseProcessor<T>> processors) -> void
+OpenTelemetry.CompositeProcessor<T>.AddProcessor(OpenTelemetry.BaseProcessor<T>! processor) -> OpenTelemetry.CompositeProcessor<T>!
+OpenTelemetry.CompositeProcessor<T>.CompositeProcessor(System.Collections.Generic.IEnumerable<OpenTelemetry.BaseProcessor<T>!>! processors) -> void
 OpenTelemetry.ExportProcessorType
 OpenTelemetry.ExportProcessorType.Batch = 1 -> OpenTelemetry.ExportProcessorType
 OpenTelemetry.ExportProcessorType.Simple = 0 -> OpenTelemetry.ExportProcessorType

src/OpenTelemetry/CompositeProcessor.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
@@ -24,7 +26,7 @@ namespace OpenTelemetry
 {
     public class CompositeProcessor<T> : BaseProcessor<T>
     {
-        private readonly DoublyLinkedListNode head;
+        internal readonly DoublyLinkedListNode Head;
         private DoublyLinkedListNode tail;
         private bool disposed;
 
@@ -38,8 +40,8 @@ public CompositeProcessor(IEnumerable<BaseProcessor<T>> processors)
                 throw new ArgumentException($"'{iter}' is null or empty", nameof(iter));
             }
 
-            this.head = new DoublyLinkedListNode(iter.Current);
-            this.tail = this.head;
+            this.Head = new DoublyLinkedListNode(iter.Current);
+            this.tail = this.Head;
 
             while (iter.MoveNext())
             {
@@ -64,7 +66,7 @@ public CompositeProcessor<T> AddProcessor(BaseProcessor<T> processor)
         /// <inheritdoc/>
         public override void OnEnd(T data)
         {
-            for (var cur = this.head; cur != null; cur = cur.Next)
+            for (var cur = this.Head; cur != null; cur = cur.Next)
             {
                 cur.Value.OnEnd(data);
             }
@@ -73,7 +75,7 @@ public override void OnEnd(T data)
         /// <inheritdoc/>
         public override void OnStart(T data)
         {
-            for (var cur = this.head; cur != null; cur = cur.Next)
+            for (var cur = this.Head; cur != null; cur = cur.Next)
             {
                 cur.Value.OnStart(data);
             }
@@ -87,7 +89,7 @@ protected override bool OnForceFlush(int timeoutMilliseconds)
                 ? null
                 : Stopwatch.StartNew();
 
-            for (var cur = this.head; cur != null; cur = cur.Next)
+            for (var cur = this.Head; cur != null; cur = cur.Next)
             {
                 if (sw == null)
                 {
@@ -113,7 +115,7 @@ protected override bool OnShutdown(int timeoutMilliseconds)
                 ? null
                 : Stopwatch.StartNew();
 
-            for (var cur = this.head; cur != null; cur = cur.Next)
+            for (var cur = this.Head; cur != null; cur = cur.Next)
             {
                 if (sw == null)
                 {
@@ -138,7 +140,7 @@ protected override void Dispose(bool disposing)
             {
                 if (disposing)
                 {
-                    for (var cur = this.head; cur != null; cur = cur.Next)
+                    for (var cur = this.Head; cur != null; cur = cur.Next)
                     {
                         try
                         {
@@ -157,7 +159,7 @@ protected override void Dispose(bool disposing)
             base.Dispose(disposing);
         }
 
-        private class DoublyLinkedListNode
+        internal sealed class DoublyLinkedListNode
         {
             public readonly BaseProcessor<T> Value;
 
@@ -166,9 +168,9 @@ public DoublyLinkedListNode(BaseProcessor<T> value)
                 this.Value = value;
             }
 
-            public DoublyLinkedListNode Previous { get; set; }
+            public DoublyLinkedListNode? Previous { get; set; }
 
-            public DoublyLinkedListNode Next { get; set; }
+            public DoublyLinkedListNode? Next { get; set; }
         }
     }
 }

src/OpenTelemetry/Logs/OpenTelemetryLogger.cs

@@ -57,7 +57,7 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
 
                 record.ScopeProvider = provider.IncludeScopes ? this.ScopeProvider : null;
                 record.State = provider.ParseStateValues ? null : state;
-                record.StateValues = provider.ParseStateValues ? this.ParseState(record, state) : null;
+                record.StateValues = provider.ParseStateValues ? this.ParseState(record, state, provider.HasBatchProcessor) : null;
 
                 ref LogRecordData data = ref record.Data;
 
@@ -88,7 +88,7 @@ public bool IsEnabled(LogLevel logLevel)
 
         public IDisposable BeginScope<TState>(TState state) => this.ScopeProvider?.Push(state) ?? NullScope.Instance;
 
-        private IReadOnlyList<KeyValuePair<string, object?>> ParseState<TState>(LogRecord logRecord, TState state)
+        private IReadOnlyList<KeyValuePair<string, object?>> ParseState<TState>(LogRecord logRecord, TState state, bool buffer)
         {
             if (state is LogRecordAttributeList logRecordAttributes)
             {
@@ -97,6 +97,12 @@ public bool IsEnabled(LogLevel logLevel)
             }
             else if (state is IReadOnlyList<KeyValuePair<string, object?>> stateList)
             {
+                if (!buffer)
+                {
+                    return stateList;
+                }
+
+                // Note: Buffering is needed to fix: https://github.com/open-telemetry/opentelemetry-dotnet/issues/2905
                 var attributeStorage = logRecord.AttributeStorage ??= new List<KeyValuePair<string, object?>>(stateList.Count);
                 attributeStorage.AddRange(stateList);
                 return attributeStorage;

src/OpenTelemetry/Logs/OpenTelemetryLoggerProvider.cs

@@ -34,6 +34,7 @@ public class OpenTelemetryLoggerProvider : BaseProvider, ILoggerProvider, ISuppo
         internal readonly bool IncludeFormattedMessage;
         internal readonly bool ParseStateValues;
         internal BaseProcessor<LogRecord>? Processor;
+        internal bool HasBatchProcessor;
         internal Resource Resource;
         private readonly Hashtable loggers = new();
         private bool disposed;
@@ -124,6 +125,11 @@ internal OpenTelemetryLoggerProvider AddProcessor(BaseProcessor<LogRecord> proce
 
             processor.SetParentProvider(this);
 
+            if (!this.HasBatchProcessor)
+            {
+                this.InspectProcessor(processor);
+            }
+
             if (this.Processor == null)
             {
                 this.Processor = processor;
@@ -162,5 +168,27 @@ protected override void Dispose(bool disposing)
 
             base.Dispose(disposing);
         }
+
+        private void InspectProcessor(BaseProcessor<LogRecord> processor)
+        {
+            if (processor is BatchExportProcessor<LogRecord>)
+            {
+                this.HasBatchProcessor = true;
+            }
+            else if (processor is CompositeProcessor<LogRecord> compositeProcessor)
+            {
+                var current = compositeProcessor.Head;
+                while (current != null)
+                {
+                    this.InspectProcessor(current.Value);
+                    if (this.HasBatchProcessor)
+                    {
+                        return;
+                    }
+
+                    current = current.Next;
+                }
+            }
+        }
     }
 }