feat(otlp)!: Export OTLP spans with attribute-level OTel compatibility

libdd-data-pipeline/src/otlp/config.rs

@@ -35,4 +35,7 @@ pub struct OtlpTraceConfig {
     /// Protocol (for future use; currently only HttpJson is supported).
     #[allow(dead_code)]
     pub(crate) protocol: OtlpProtocol,
+    /// When `true`, does not add DD-specific per-span attributes (`service.name`,
+    /// `operation.name`, `resource.name`, `span.type`) to the OTLP payload.
+    pub otel_trace_semantics_enabled: bool,
 }

libdd-data-pipeline/src/trace_exporter/builder.rs

@@ -65,6 +65,7 @@ pub struct TraceExporterBuilder {
     connection_timeout: Option<u64>,
     otlp_endpoint: Option<String>,
     otlp_headers: Vec<(String, String)>,
+    otel_trace_semantics_enabled: bool,
 }
 
 impl TraceExporterBuilder {
@@ -296,6 +297,16 @@ impl TraceExporterBuilder {
         self
     }
 
+    /// Enables OTel trace semantics, which does not add DD-specific per-span attributes
+    /// (`service.name`, `operation.name`, `resource.name`, `span.type`) to the OTLP payload.
+    /// This is useful when exporting to a native OTel backend that does not expect Datadog
+    /// semantics. The host language tracer is expected to observe this behavior by setting the
+    /// `DD_TRACE_OTEL_SEMANTICS_ENABLED` environment variable to `true`.
+    pub fn enable_otel_trace_semantics(&mut self) -> &mut Self {
+        self.otel_trace_semantics_enabled = true;
+        self
+    }
+
     /// Build the [`TraceExporter`] synchronously.
     ///
     /// Sync facade over [`Self::build_async`]; panics inside an existing tokio context.
@@ -452,6 +463,7 @@ impl TraceExporterBuilder {
                     .map(Duration::from_millis)
                     .unwrap_or(DEFAULT_OTLP_TIMEOUT),
                 protocol: OtlpProtocol::HttpJson,
+                otel_trace_semantics_enabled: self.otel_trace_semantics_enabled,
             }
         });
 

libdd-data-pipeline/src/trace_exporter/mod.rs

@@ -545,7 +545,8 @@ impl<C: HttpClientCapability + SleepCapability + MaybeSend + Sync + 'static> Tra
             r.runtime_id = self.metadata.runtime_id.clone();
             r
         };
-        let request = map_traces_to_otlp(traces, &resource_info);
+        let request =
+            map_traces_to_otlp(traces, &resource_info, config.otel_trace_semantics_enabled);
         let json_body = serde_json::to_vec(&request).map_err(|e| {
             error!("OTLP JSON serialization error: {e}");
             TraceExporterError::Internal(InternalErrorKind::InvalidWorkerState(e.to_string()))