Add _dd.svc_src meta tag to track service name source

tracer/build/smoke_test_snapshots/smoke_test_iis_snapshots.json

@@ -62,7 +62,8 @@
         "_dd.p.tid": "67a4e73b00000000",
         "runtime-id": "05dff020-c9cc-4b50-9395-e1fe88603312",
         "language": "dotnet",
-        "_dd.base_service": "AspNetCoreSmokeTest"
+        "_dd.base_service": "AspNetCoreSmokeTest",
+        "_dd.svc_src": "http-client"
       },
       "metrics": {
         "_dd.tracer_kr": 0.0,

tracer/build/smoke_test_snapshots/smoke_test_snapshots.json

@@ -18,7 +18,8 @@
         "out.host": "localhost",
         "runtime-id": "11c61d09-16bb-477f-87ab-4f81d656c5ca",
         "span.kind": "client",
-        "_dd.base_service": "AspNetCoreSmokeTest"
+        "_dd.base_service": "AspNetCoreSmokeTest",
+        "_dd.svc_src": "http-client"
       },
       "metrics": {
         "_dd.top_level": 1.0,

tracer/build/smoke_test_snapshots/smoke_test_snapshots_2_1.json

@@ -18,7 +18,8 @@
         "out.host": "localhost",
         "runtime-id": "b34b2bed-9444-4597-87f6-b8202b03b1b8",
         "span.kind": "client",
-        "_dd.base_service": "AspNetCoreSmokeTest"
+        "_dd.base_service": "AspNetCoreSmokeTest",
+        "_dd.svc_src": "http-client"
       },
       "metrics": {
         "_dd.top_level": 1.0,

tracer/src/Datadog.Trace/Agent/MessagePack/SpanMessagePackFormatter.cs

@@ -1,4 +1,4 @@
-// <copyright file="SpanMessagePackFormatter.cs" company="Datadog">
+// <copyright file="SpanMessagePackFormatter.cs" company="Datadog">
 // Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2 License.
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2017 Datadog, Inc.
 // </copyright>
@@ -82,6 +82,7 @@ internal sealed class SpanMessagePackFormatter : IMessagePackFormatter<TraceChun
         private readonly byte[] _originNameBytes = StringEncoding.UTF8.GetBytes(Trace.Tags.Origin);
         private readonly byte[] _lastParentIdBytes = StringEncoding.UTF8.GetBytes(Trace.Tags.LastParentId);
         private readonly byte[] _baseServiceNameBytes = StringEncoding.UTF8.GetBytes(Trace.Tags.BaseService);
+        private readonly byte[] _serviceNameSourceNameBytes = StringEncoding.UTF8.GetBytes(Trace.Tags.ServiceNameSource);
 
         // numeric tags
         private readonly byte[] _metricsBytes = StringEncoding.UTF8.GetBytes("metrics");
@@ -610,6 +611,22 @@ private int WriteTags(ref byte[] bytes, int offset, in SpanModel model, ITagProc
                 }
             }
 
+            // add _dd.svc_src tag to indicate which integration set the service name
+            // Safety: if the service name equals the default, clear the source — unless it's a
+            // configuration-driven override (opt.*), which should always be preserved.
+            var serviceNameSource = span.Context.ServiceNameSource;
+            if (serviceNameEqualsDefault && serviceNameSource?.StartsWith("opt.", StringComparison.Ordinal) != true)
+            {
+                serviceNameSource = null;
+            }
+
+            if (serviceNameSource is not null)
+            {
+                count++;
+                offset += MessagePackBinary.WriteStringBytes(ref bytes, offset, _serviceNameSourceNameBytes);
+                offset += MessagePackBinary.WriteString(ref bytes, offset, serviceNameSource);
+            }
+
             // Process tags will be sent only once per buffer/payload (one payload can contain many chunks from different traces)
             if (model.IsFirstSpanInChunk && model.TraceChunk.IsFirstChunkInPayload && model.TraceChunk.ShouldPropagateProcessTags)
             {

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/DynamoDb/AwsDynamoDbCommon.cs

@@ -39,8 +39,8 @@ internal static class AwsDynamoDbCommon
             try
             {
                 tags = perTraceSettings.Schema.Database.CreateAwsDynamoDbTags();
-                var serviceName = perTraceSettings.GetServiceName(DatadogAwsDynamoDbServiceName);
-                scope = tracer.StartActiveInternal(DynamoDbOperationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsDynamoDbServiceName);
+                scope = tracer.StartActiveInternal(DynamoDbOperationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 // This is needed to showcase the DynamoDB action in the

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/EventBridge/AwsEventBridgeCommon.cs

@@ -41,9 +41,9 @@ internal static class AwsEventBridgeCommon
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsEventBridgeTags(spanKind);
-                var serviceName = perTraceSettings.GetServiceName(DatadogAwsEventBridgeServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsEventBridgeServiceName);
                 var operationName = GetOperationName(tracer);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/Kinesis/AwsKinesisCommon.cs

@@ -60,9 +60,9 @@ internal static class AwsKinesisCommon
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsKinesisTags(spanKind);
-                string serviceName = perTraceSettings.GetServiceName(DatadogAwsKinesisServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsKinesisServiceName);
                 string operationName = perTraceSettings.Schema.Messaging.GetOutboundOperationName(MessagingSchema.OperationType.AwsKinesis);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/S3/AwsS3Common.cs

@@ -38,9 +38,9 @@ internal static class AwsS3Common
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsS3Tags(spanKind);
-                var serviceName = perTraceSettings.GetServiceName(DatadogAwsS3ServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsS3ServiceName);
                 var operationName = GetOperationName(tracer);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/SNS/AwsSnsCommon.cs

@@ -40,9 +40,9 @@ internal static class AwsSnsCommon
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsSnsTags(spanKind);
-                var serviceName = perTraceSettings.GetServiceName(DatadogAwsSnsServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsSnsServiceName);
                 var operationName = GetOperationName(tracer, spanKind);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/SQS/AwsSqsCommon.cs

@@ -40,9 +40,9 @@ internal static class AwsSqsCommon
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsSqsTags(spanKind);
-                string serviceName = perTraceSettings.GetServiceName(DatadogAwsSqsServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsSqsServiceName);
                 string operationName = GetOperationName(tracer, spanKind);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/StepFunctions/AwsStepFunctionsCommon.cs

@@ -39,9 +39,9 @@ internal static class AwsStepFunctionsCommon
             try
             {
                 tags = perTraceSettings.Schema.Messaging.CreateAwsStepFunctionsTags(spanKind);
-                var serviceName = perTraceSettings.GetServiceName(DatadogAwsStepFunctionsServiceName);
+                var (serviceName, serviceNameSource) = perTraceSettings.GetServiceNameMetadata(DatadogAwsStepFunctionsServiceName);
                 var operationName = GetOperationName(tracer, spanKind);
-                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, parent: parentContext, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 span.Type = SpanTypes.Http;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AdoNet/DbScopeFactory.cs

@@ -12,6 +12,7 @@
 using System.Threading;
 using Datadog.Trace.AppSec;
 using Datadog.Trace.Configuration;
+using Datadog.Trace.Configuration.Schema;
 using Datadog.Trace.DatabaseMonitoring;
 using Datadog.Trace.Logging;
 using Datadog.Trace.Tagging;
@@ -24,7 +25,7 @@ internal static class DbScopeFactory
         private static readonly IDatadogLogger Log = DatadogLogging.GetLoggerFor(typeof(DbScopeFactory));
         private static bool _dbCommandCachingLogged = false;
 
-        private static Scope? CreateDbCommandScope(Tracer tracer, IDbCommand command, IntegrationId integrationId, string dbType, string operationName, string serviceName, ref DbCommandCache.TagsCacheItem tagsFromConnectionString)
+        private static Scope? CreateDbCommandScope(Tracer tracer, IDbCommand command, IntegrationId integrationId, string dbType, string operationName, string serviceName, string? serviceNameSource, ref DbCommandCache.TagsCacheItem tagsFromConnectionString)
         {
             var perTraceSettings = tracer.CurrentTraceSettings;
             if (!perTraceSettings.Settings.IsIntegrationEnabled(integrationId) || !perTraceSettings.Settings.IsIntegrationEnabled(IntegrationId.AdoNet))
@@ -64,7 +65,7 @@ internal static class DbScopeFactory
                 tags.SetAnalyticsSampleRate(integrationId, perTraceSettings.Settings, enabledWithGlobalSetting: false);
                 perTraceSettings.Schema.RemapPeerService(tags);
 
-                scope = tracer.StartActiveInternal(operationName, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(operationName, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 scope.Span.ResourceName = commandText;
                 scope.Span.Type = SpanTypes.Sql;
                 tracer.TracerManager.Telemetry.IntegrationGeneratedSpan(integrationId);
@@ -236,7 +237,7 @@ public static class Cache<TCommand>
             private static readonly IntegrationId IntegrationId;
 
             // ServiceName cache
-            private static KeyValuePair<string, string> _serviceNameCache;
+            private static KeyValuePair<string, ServiceNameMetadata> _serviceNameCache;
 
             // ConnectionString tags cache
             private static KeyValuePair<string, DbCommandCache.TagsCacheItem> _tagsByConnectionStringCache;
@@ -264,13 +265,15 @@ static Cache()
                     // use the cached values if command.GetType() == typeof(TCommand)
                     // and we successfully called TryGetIntegrationDetails() in the ctor
                     var tagsFromConnectionString = GetTagsFromConnectionString(command);
+                    var (cachedServiceName, cachedServiceNameSource) = GetServiceNameMetadata(tracer, DbTypeName);
                     return DbScopeFactory.CreateDbCommandScope(
                         tracer: tracer,
                         command: command,
                         integrationId: IntegrationId,
                         dbType: DbTypeName,
                         operationName: OperationName,
-                        serviceName: GetServiceName(tracer, DbTypeName),
+                        serviceName: cachedServiceName,
+                        serviceNameSource: cachedServiceNameSource,
                         tagsFromConnectionString: ref tagsFromConnectionString);
                 }
 
@@ -280,47 +283,51 @@ static Cache()
                 {
                     var operationName = $"{dbTypeName}.query";
                     var tagsFromConnectionString = GetTagsFromConnectionString(command);
+                    var (resolvedServiceName, resolvedServiceNameSource) = GetServiceNameMetadata(tracer, dbTypeName);
                     return DbScopeFactory.CreateDbCommandScope(
                         tracer: tracer,
                         command: command,
                         integrationId: integrationId.Value,
                         dbType: dbTypeName,
                         operationName: operationName,
-                        serviceName: GetServiceName(tracer, dbTypeName),
+                        serviceName: resolvedServiceName,
+                        serviceNameSource: resolvedServiceNameSource,
                         tagsFromConnectionString: ref tagsFromConnectionString);
                 }
 
                 return null;
             }
 
-            private static string GetServiceName(Tracer tracer, string dbTypeName)
+            private static ServiceNameMetadata GetServiceNameMetadata(Tracer tracer, string dbTypeName)
             {
-                if (!tracer.CurrentTraceSettings.ServiceNames.TryGetValue(dbTypeName, out var serviceName))
+                if (tracer.CurrentTraceSettings.ServiceNames.TryGetValue(dbTypeName, out var serviceName))
                 {
-                    if (DbTypeName != dbTypeName)
-                    {
-                        // We cannot cache in the base class
-                        return tracer.CurrentTraceSettings.GetServiceName(dbTypeName);
-                    }
+                    return new ServiceNameMetadata(serviceName, ServiceNameMetadata.OptServiceMapping);
+                }
 
-                    var serviceNameCache = _serviceNameCache;
+                if (DbTypeName != dbTypeName)
+                {
+                    // We cannot cache in the base class
+                    return tracer.CurrentTraceSettings.GetServiceNameMetadata(dbTypeName);
+                }
 
-                    // If not a base class
-                    if (serviceNameCache.Key == tracer.DefaultServiceName)
-                    {
-                        // Service has not changed
-                        // Fastpath
-                        return serviceNameCache.Value;
-                    }
+                var serviceNameCache = _serviceNameCache;
 
-                    // We create or replace the cache with the new service name
-                    // Slowpath
-                    var defaultServiceName = tracer.DefaultServiceName;
-                    serviceName = tracer.CurrentTraceSettings.GetServiceName(dbTypeName);
-                    _serviceNameCache = new KeyValuePair<string, string>(defaultServiceName, serviceName);
+                // If not a base class
+                if (serviceNameCache.Key == tracer.DefaultServiceName)
+                {
+                    // Service has not changed
+                    // Fastpath
+                    return serviceNameCache.Value;
                 }
 
-                return serviceName;
+                // We create or replace the cache with the new service name
+                // Slowpath
+                var defaultServiceName = tracer.DefaultServiceName;
+                var metadata = tracer.CurrentTraceSettings.GetServiceNameMetadata(dbTypeName);
+                _serviceNameCache = new KeyValuePair<string, ServiceNameMetadata>(defaultServiceName, metadata);
+
+                return metadata;
             }
 
             private static DbCommandCache.TagsCacheItem GetTagsFromConnectionString(IDbCommand command)

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/Aerospike/AerospikeCommon.cs

@@ -34,10 +34,10 @@ public static Scope CreateScope<TTarget>(Tracer tracer, TTarget target)
 
             try
             {
-                var serviceName = perTraceSettings.Schema.Database.GetServiceName(DatabaseSchema.ServiceType.Aerospike);
+                var (serviceName, serviceNameSource) = perTraceSettings.Schema.Database.GetServiceNameMetadata(DatabaseSchema.ServiceType.Aerospike);
                 var tags = perTraceSettings.Schema.Database.CreateAerospikeTags();
 
-                scope = tracer.StartActiveInternal(OperationName, tags: tags, serviceName: serviceName);
+                scope = tracer.StartActiveInternal(OperationName, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource);
                 var span = scope.Span;
 
                 if (target.TryDuckCast<HasKey>(out var hasKey))

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/Azure/EventHubs/AmqpConsumerReceiveAsyncIntegration.cs

@@ -118,8 +118,8 @@ private static void ProcessReceivedEvents(IReadOnlyList<object> eventsList, IAmq
         var tags = Tracer.Instance.CurrentTraceSettings.Schema.Messaging.CreateAzureEventHubsTags(SpanKinds.Consumer);
         tags.MessagingOperation = OperationName;
 
-        string serviceName = tracer.CurrentTraceSettings.Schema.Messaging.GetServiceName(MessagingSchema.ServiceType.AzureEventHubs);
-        var scope = tracer.StartActiveInternal(SpanOperationName, tags: tags, serviceName: serviceName, links: spanLinks);
+        var (serviceName, serviceNameSource) = tracer.CurrentTraceSettings.Schema.Messaging.GetServiceNameMetadata(MessagingSchema.ServiceType.AzureEventHubs);
+        var scope = tracer.StartActiveInternal(SpanOperationName, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource, links: spanLinks);
         var span = scope.Span;
 
         var eventHubName = consumerInstance.EventHubName;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/Azure/EventHubs/EventHubsCommon.cs

@@ -87,8 +87,8 @@ private static CallTargetState CreateSenderSpanInternal(
             tags.MessagingDestinationName = eventHubName;
             tags.MessagingOperation = operationName;
 
-            string serviceName = tracer.CurrentTraceSettings.Schema.Messaging.GetServiceName(MessagingSchema.ServiceType.AzureEventHubs);
-            scope = tracer.StartActiveInternal("azure_eventhubs." + operationName, tags: tags, serviceName: serviceName, links: spanLinks);
+            var (serviceName, serviceNameSource) = tracer.CurrentTraceSettings.Schema.Messaging.GetServiceNameMetadata(MessagingSchema.ServiceType.AzureEventHubs);
+            scope = tracer.StartActiveInternal("azure_eventhubs." + operationName, tags: tags, serviceName: serviceName, serviceNameSource: serviceNameSource, links: spanLinks);
             var span = scope.Span;
 
             span.Type = SpanTypes.Queue;

tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/Azure/ServiceBus/AzureServiceBusCommon.cs

@@ -128,11 +128,12 @@ private static CallTargetState CreateSenderSpanInternal(
             tags.MessagingOperation = operationName;
             tags.MessagingSystem = "servicebus";
 
-            string serviceName = perTraceSettings.Schema.Messaging.GetServiceName(MessagingSchema.ServiceType.AzureServiceBus);
+            var (serviceName, serviceNameSource) = perTraceSettings.Schema.Messaging.GetServiceNameMetadata(MessagingSchema.ServiceType.AzureServiceBus);
             var scope = tracer.StartActiveInternal(
                 "azure_servicebus." + operationName,
                 tags: tags,
                 serviceName: serviceName,
+                serviceNameSource: serviceNameSource,
                 links: spanLinks);
             var span = scope.Span;