Add Filter public API to enable filtering

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/.publicApi/netstandard2.0/PublicAPI.Unshipped.txt

@@ -1,5 +1,7 @@
 OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions
 OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.EntityFrameworkInstrumentationOptions() -> void
+OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.Filter.get -> System.Func<System.Data.IDbCommand, bool>
+OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.Filter.set -> void
 OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.SetDbStatementForStoredProcedure.get -> bool
 OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.SetDbStatementForStoredProcedure.set -> void
 OpenTelemetry.Instrumentation.EntityFrameworkCore.EntityFrameworkInstrumentationOptions.SetDbStatementForText.get -> bool

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+* Added `Filter` public API on `EntityFrameworkInstrumentationOptions` to enable filtering
+  of instrumentation based on the db command being executed.
+
 ## 1.0.0-beta.6
 
 Released 2023-Mar-13

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/EntityFrameworkInstrumentationOptions.cs

@@ -44,4 +44,24 @@ public class EntityFrameworkInstrumentationOptions
     /// <para><see cref="IDbCommand"/>: db command to allow access to command.</para>
     /// </remarks>
     public Action<Activity, IDbCommand> EnrichWithIDbCommand { get; set; }
+
+    /// <summary>
+    /// Gets or sets a filter function that determines whether or not to
+    /// collect telemetry about a command.
+    /// </summary>
+    /// <remarks>
+    /// <b>Notes:</b>
+    /// <list type="bullet">
+    /// <item>The first parameter passed to the filter function is <see cref="IDbCommand"/> from which additional
+    /// information can be extracted.</item>
+    /// <item>The return value for the filter:
+    /// <list type="number">
+    /// <item>If filter returns <see langword="true" />, the command is
+    /// collected.</item>
+    /// <item>If filter returns <see langword="false" /> or throws an
+    /// exception, the command is <b>NOT</b> collected.</item>
+    /// </list></item>
+    /// </list>
+    /// </remarks>
+    public Func<IDbCommand, bool> Filter { get; set; }
 }

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/Implementation/EntityFrameworkDiagnosticListener.cs

@@ -179,6 +179,24 @@ public override void OnCustom(string name, Activity activity, object payload)
                     {
                         var command = this.commandFetcher.Fetch(payload);
 
+                        try
+                        {
+                            if (command is IDbCommand typedCommand && this.options.Filter?.Invoke(typedCommand) == false)
+                            {
+                                EntityFrameworkInstrumentationEventSource.Log.CommandIsFilteredOut(activity.OperationName);
+                                activity.IsAllDataRequested = false;
+                                activity.ActivityTraceFlags &= ~ActivityTraceFlags.Recorded;
+                                return;
+                            }
+                        }
+                        catch (Exception ex)
+                        {
+                            EntityFrameworkInstrumentationEventSource.Log.CommandFilterException(ex);
+                            activity.IsAllDataRequested = false;
+                            activity.ActivityTraceFlags &= ~ActivityTraceFlags.Recorded;
+                            return;
+                        }
+
                         if (this.commandTypeFetcher.Fetch(command) is CommandType commandType)
                         {
                             var commandText = this.commandTextFetcher.Fetch(command);

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/Implementation/EntityFrameworkInstrumentationEventSource.cs

@@ -43,6 +43,15 @@ public void EnrichmentException(string eventName, Exception ex)
         }
     }
 
+    [NonEvent]
+    public void CommandFilterException(Exception ex)
+    {
+        if (this.IsEnabled(EventLevel.Error, EventKeywords.All))
+        {
+            this.CommandFilterException(ex.ToInvariantString());
+        }
+    }
+
     [Event(1, Message = "Unknown error processing event '{1}' from handler '{0}', Exception: {2}", Level = EventLevel.Error)]
     public void UnknownErrorProcessingEvent(string handlerName, string eventName, string ex)
     {
@@ -75,4 +84,16 @@ public void EnrichmentException(string eventName, string exception)
             this.WriteEvent(5, eventName, exception);
         }
     }
+
+    [Event(6, Message = "Command is filtered out. Activity {0}", Level = EventLevel.Verbose)]
+    public void CommandIsFilteredOut(string activityName)
+    {
+        this.WriteEvent(6, activityName);
+    }
+
+    [Event(7, Message = "Command filter threw exception. Command will not be collected. Exception {0}.", Level = EventLevel.Error)]
+    public void CommandFilterException(string exception)
+    {
+        this.WriteEvent(7, exception);
+    }
 }

src/OpenTelemetry.Instrumentation.EntityFrameworkCore/README.md

@@ -112,6 +112,28 @@ services.AddOpenTelemetry()
         .AddConsoleExporter());
 ```
 
+### Filter
+
+This option can be used to filter out activities based on the properties of the
+db command object being instrumented using a `Func<IDbCommand, bool>`. The
+function receives an instance of the db command and should return `true`
+if the telemetry is to be collected, and `false` if it should not.
+
+The following code snippet shows how to use `Filter` to collect traces for stored procedures only.
+
+```csharp
+services.AddOpenTelemetry()
+    .WithTracing(builder => builder
+        .AddEntityFrameworkCoreInstrumentation(options =>
+        {
+            options.Filter = (command) =>
+            {
+                return command.CommandType == System.Data.CommandType.StoredProcedure;
+            };
+        })
+        .AddConsoleExporter());
+```
+
 ## References
 
 * [OpenTelemetry Project](https://opentelemetry.io/)

test/OpenTelemetry.Instrumentation.EntityFrameworkCore.Tests/EntityFrameworkDiagnosticListenerTests.cs

@@ -131,6 +131,60 @@ public void EntityFrameworkContextExceptionEventsInstrumentedTest()
         VerifyActivityData(activity, isError: true);
     }
 
+    [Fact]
+    public void ShouldCollectTelemetryWhenFilterEvaluatesToTrue()
+    {
+        var activityProcessor = new Mock<BaseProcessor<Activity>>();
+        using var shutdownSignal = Sdk.CreateTracerProviderBuilder()
+            .AddProcessor(activityProcessor.Object)
+            .AddEntityFrameworkCoreInstrumentation(options =>
+            {
+                options.Filter = (command) =>
+                {
+                    return command.CommandText.Contains("Item", StringComparison.OrdinalIgnoreCase);
+                };
+            }).Build();
+
+        using (var context = new ItemsContext(this.contextOptions))
+        {
+            _ = context.Set<Item>().OrderBy(e => e.Name).ToList();
+        }
+
+        Assert.Equal(3, activityProcessor.Invocations.Count);
+
+        var activity = (Activity)activityProcessor.Invocations[1].Arguments[0];
+
+        Assert.True(activity.IsAllDataRequested);
+        Assert.True(activity.ActivityTraceFlags.HasFlag(ActivityTraceFlags.Recorded));
+    }
+
+    [Fact]
+    public void ShouldCollectTelemetryWhenFilterEvaluatesToFalse()
+    {
+        var activityProcessor = new Mock<BaseProcessor<Activity>>();
+        using var shutdownSignal = Sdk.CreateTracerProviderBuilder()
+            .AddProcessor(activityProcessor.Object)
+            .AddEntityFrameworkCoreInstrumentation(options =>
+            {
+                options.Filter = (command) =>
+                {
+                    return !command.CommandText.Contains("Item", StringComparison.OrdinalIgnoreCase);
+                };
+            }).Build();
+
+        using (var context = new ItemsContext(this.contextOptions))
+        {
+            _ = context.Set<Item>().OrderBy(e => e.Name).ToList();
+        }
+
+        Assert.Equal(2, activityProcessor.Invocations.Count);
+
+        var activity = (Activity)activityProcessor.Invocations[1].Arguments[0];
+
+        Assert.False(activity.IsAllDataRequested);
+        Assert.True(activity.ActivityTraceFlags.HasFlag(ActivityTraceFlags.None));
+    }
+
     public void Dispose() => this.connection.Dispose();
 
     private static DbConnection CreateInMemoryDatabase()