[sqlclient] Make SqlClientInstrumentation a singleton

src/OpenTelemetry.Instrumentation.SqlClient/Implementation/SqlClientDiagnosticListener.cs

@@ -34,18 +34,22 @@ internal sealed class SqlClientDiagnosticListener : ListenerHandler
     private readonly PropertyFetcher<object> commandTextFetcher = new("CommandText");
     private readonly PropertyFetcher<Exception> exceptionFetcher = new("Exception");
     private readonly PropertyFetcher<int> exceptionNumberFetcher = new("Number");
-    private readonly SqlClientTraceInstrumentationOptions options;
 
-    public SqlClientDiagnosticListener(string sourceName, SqlClientTraceInstrumentationOptions? options)
+    public SqlClientDiagnosticListener(string sourceName)
         : base(sourceName)
     {
-        this.options = options ?? new SqlClientTraceInstrumentationOptions();
     }
 
     public override bool SupportsNullActivity => true;
 
     public override void OnEventWritten(string name, object? payload)
     {
+        if (SqlClientInstrumentation.TracingHandles == 0)
+        {
+            return;
+        }
+
+        var options = SqlClientInstrumentation.TracingOptions;
         var activity = Activity.Current;
         switch (name)
         {
@@ -63,7 +67,7 @@ public override void OnEventWritten(string name, object? payload)
                     _ = this.databaseFetcher.TryFetch(connection, out var databaseName);
                     _ = this.dataSourceFetcher.TryFetch(connection, out var dataSource);
 
-                    var startTags = SqlActivitySourceHelper.GetTagListFromConnectionInfo(dataSource, databaseName, this.options, out var activityName);
+                    var startTags = SqlActivitySourceHelper.GetTagListFromConnectionInfo(dataSource, databaseName, options, out var activityName);
                     activity = SqlActivitySourceHelper.ActivitySource.StartActivity(
                         activityName,
                         ActivityKind.Client,
@@ -80,7 +84,7 @@ public override void OnEventWritten(string name, object? payload)
                     {
                         try
                         {
-                            if (this.options.Filter?.Invoke(command) == false)
+                            if (options.Filter?.Invoke(command) == false)
                             {
                                 SqlClientInstrumentationEventSource.Log.CommandIsFilteredOut(activity.OperationName);
                                 activity.IsAllDataRequested = false;
@@ -103,12 +107,12 @@ public override void OnEventWritten(string name, object? payload)
                             switch (commandType)
                             {
                                 case CommandType.StoredProcedure:
-                                    if (this.options.EmitOldAttributes)
+                                    if (options.EmitOldAttributes)
                                     {
                                         activity.SetTag(SemanticConventions.AttributeDbStatement, commandText);
                                     }
 
-                                    if (this.options.EmitNewAttributes)
+                                    if (options.EmitNewAttributes)
                                     {
                                         activity.SetTag(SemanticConventions.AttributeDbOperationName, "EXECUTE");
                                         activity.SetTag(SemanticConventions.AttributeDbCollectionName, commandText);
@@ -118,14 +122,14 @@ public override void OnEventWritten(string name, object? payload)
                                     break;
 
                                 case CommandType.Text:
-                                    if (this.options.SetDbStatementForText)
+                                    if (options.SetDbStatementForText)
                                     {
-                                        if (this.options.EmitOldAttributes)
+                                        if (options.EmitOldAttributes)
                                         {
                                             activity.SetTag(SemanticConventions.AttributeDbStatement, commandText);
                                         }
 
-                                        if (this.options.EmitNewAttributes)
+                                        if (options.EmitNewAttributes)
                                         {
                                             activity.SetTag(SemanticConventions.AttributeDbQueryText, commandText);
                                         }
@@ -142,7 +146,7 @@ public override void OnEventWritten(string name, object? payload)
 
                         try
                         {
-                            this.options.Enrich?.Invoke(activity, "OnCustom", command);
+                            options.Enrich?.Invoke(activity, "OnCustom", command);
                         }
                         catch (Exception ex)
                         {
@@ -199,7 +203,7 @@ public override void OnEventWritten(string name, object? payload)
 
                                 activity.SetStatus(ActivityStatusCode.Error, exception.Message);
 
-                                if (this.options.RecordException)
+                                if (options.RecordException)
                                 {
                                     activity.RecordException(exception);
                                 }

src/OpenTelemetry.Instrumentation.SqlClient/Implementation/SqlEventSourceListener.netfx.cs

@@ -29,15 +29,9 @@ internal sealed class SqlEventSourceListener : EventListener
     internal const int BeginExecuteEventId = 1;
     internal const int EndExecuteEventId = 2;
 
-    private readonly SqlClientTraceInstrumentationOptions options;
     private EventSource? adoNetEventSource;
     private EventSource? mdsEventSource;
 
-    public SqlEventSourceListener(SqlClientTraceInstrumentationOptions? options = null)
-    {
-        this.options = options ?? new SqlClientTraceInstrumentationOptions();
-    }
-
     public override void Dispose()
     {
         if (this.adoNetEventSource != null)
@@ -106,6 +100,13 @@ private void OnBeginExecute(EventWrittenEventArgs eventData)
                 (https://github.com/dotnet/SqlClient/blob/f4568ce68da21db3fe88c0e72e1287368aaa1dc8/src/Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/SqlCommand.cs#L6641)
          */
 
+        if (SqlClientInstrumentation.TracingHandles == 0)
+        {
+            return;
+        }
+
+        var options = SqlClientInstrumentation.TracingOptions;
+
         if (eventData.Payload.Count < 4)
         {
             SqlClientInstrumentationEventSource.Log.InvalidPayload(nameof(SqlEventSourceListener), nameof(this.OnBeginExecute));
@@ -114,7 +115,7 @@ private void OnBeginExecute(EventWrittenEventArgs eventData)
 
         var dataSource = (string)eventData.Payload[1];
         var databaseName = (string)eventData.Payload[2];
-        var startTags = SqlActivitySourceHelper.GetTagListFromConnectionInfo(dataSource, databaseName, this.options, out var activityName);
+        var startTags = SqlActivitySourceHelper.GetTagListFromConnectionInfo(dataSource, databaseName, options, out var activityName);
         var activity = SqlActivitySourceHelper.ActivitySource.StartActivity(
             activityName,
             ActivityKind.Client,
@@ -130,14 +131,14 @@ private void OnBeginExecute(EventWrittenEventArgs eventData)
         if (activity.IsAllDataRequested)
         {
             var commandText = (string)eventData.Payload[3];
-            if (!string.IsNullOrEmpty(commandText) && this.options.SetDbStatementForText)
+            if (!string.IsNullOrEmpty(commandText) && options.SetDbStatementForText)
             {
-                if (this.options.EmitOldAttributes)
+                if (options.EmitOldAttributes)
                 {
                     activity.SetTag(SemanticConventions.AttributeDbStatement, commandText);
                 }
 
-                if (this.options.EmitNewAttributes)
+                if (options.EmitNewAttributes)
                 {
                     activity.SetTag(SemanticConventions.AttributeDbQueryText, commandText);
                 }
@@ -154,6 +155,11 @@ private void OnEndExecute(EventWrittenEventArgs eventData)
             [2] -> SqlExceptionNumber
          */
 
+        if (SqlClientInstrumentation.TracingHandles == 0)
+        {
+            return;
+        }
+
         if (eventData.Payload.Count < 3)
         {
             SqlClientInstrumentationEventSource.Log.InvalidPayload(nameof(SqlEventSourceListener), nameof(this.OnEndExecute));

src/OpenTelemetry.Instrumentation.SqlClient/SqlClientInstrumentation.cs

@@ -11,12 +11,18 @@ namespace OpenTelemetry.Instrumentation.SqlClient;
 /// <summary>
 /// SqlClient instrumentation.
 /// </summary>
+#if NET
+[RequiresUnreferencedCode(SqlClientTrimmingUnsupportedMessage)]
+#endif
 internal sealed class SqlClientInstrumentation : IDisposable
 {
+    public static readonly SqlClientInstrumentation Instance = new SqlClientInstrumentation();
+
     internal const string SqlClientDiagnosticListenerName = "SqlClientDiagnosticListener";
 #if NET
     internal const string SqlClientTrimmingUnsupportedMessage = "Trimming is not yet supported with SqlClient instrumentation.";
 #endif
+    internal static int TracingHandles;
 #if NETFRAMEWORK
     private readonly SqlEventSourceListener sqlEventSourceListener;
 #else
@@ -39,25 +45,24 @@ internal sealed class SqlClientInstrumentation : IDisposable
     /// <summary>
     /// Initializes a new instance of the <see cref="SqlClientInstrumentation"/> class.
     /// </summary>
-    /// <param name="options">Configuration options for sql instrumentation.</param>
-#if NET
-    [RequiresUnreferencedCode(SqlClientTrimmingUnsupportedMessage)]
-#endif
-    public SqlClientInstrumentation(
-        SqlClientTraceInstrumentationOptions? options = null)
+    private SqlClientInstrumentation()
     {
 #if NETFRAMEWORK
-        this.sqlEventSourceListener = new SqlEventSourceListener(options);
+        this.sqlEventSourceListener = new SqlEventSourceListener();
 #else
         this.diagnosticSourceSubscriber = new DiagnosticSourceSubscriber(
-           name => new SqlClientDiagnosticListener(name, options),
+           name => new SqlClientDiagnosticListener(name),
            listener => listener.Name == SqlClientDiagnosticListenerName,
            this.isEnabled,
            SqlClientInstrumentationEventSource.Log.UnknownErrorProcessingEvent);
         this.diagnosticSourceSubscriber.Subscribe();
 #endif
     }
 
+    public static SqlClientTraceInstrumentationOptions TracingOptions { get; set; } = new SqlClientTraceInstrumentationOptions();
+
+    public static IDisposable AddTracingHandle() => new TracingHandle();
+
     /// <inheritdoc/>
     public void Dispose()
     {
@@ -67,4 +72,26 @@ public void Dispose()
         this.diagnosticSourceSubscriber?.Dispose();
 #endif
     }
+
+#if NET
+    [RequiresUnreferencedCode(SqlClientTrimmingUnsupportedMessage)]
+#endif
+    private sealed class TracingHandle : IDisposable
+    {
+        private bool disposed;
+
+        public TracingHandle()
+        {
+            Interlocked.Increment(ref TracingHandles);
+        }
+
+        public void Dispose()
+        {
+            if (!this.disposed)
+            {
+                Interlocked.Decrement(ref TracingHandles);
+                this.disposed = true;
+            }
+        }
+    }
 }

src/OpenTelemetry.Instrumentation.SqlClient/TracerProviderBuilderExtensions.cs

@@ -52,7 +52,6 @@ public static TracerProviderBuilder AddSqlClientInstrumentation(
 #if NET
     [RequiresUnreferencedCode(SqlClientInstrumentation.SqlClientTrimmingUnsupportedMessage)]
 #endif
-
     public static TracerProviderBuilder AddSqlClientInstrumentation(
         this TracerProviderBuilder builder,
         string? name,
@@ -70,8 +69,8 @@ public static TracerProviderBuilder AddSqlClientInstrumentation(
         builder.AddInstrumentation(sp =>
         {
             var sqlOptions = sp.GetRequiredService<IOptionsMonitor<SqlClientTraceInstrumentationOptions>>().Get(name);
-
-            return new SqlClientInstrumentation(sqlOptions);
+            SqlClientInstrumentation.TracingOptions = sqlOptions;
+            return SqlClientInstrumentation.AddTracingHandle();
         });
 
         builder.AddSource(SqlActivitySourceHelper.ActivitySourceName);