feat: enable AFE and gRPC metrics for DP

Author: surbhigarg92

google-cloud-spanner/src/main/java/com/google/cloud/spanner/SpannerOptions.java

@@ -1994,7 +1994,8 @@ public ApiTracerFactory getApiTracerFactory() {
   }
 
   public void enablegRPCMetrics(InstantiatingGrpcChannelProvider.Builder channelProviderBuilder) {
-    if (SpannerOptions.environment.isEnableGRPCBuiltInMetrics()) {
+    if (GapicSpannerRpc.isEnableDirectPathXdsEnv()
+        || SpannerOptions.environment.isEnableGRPCBuiltInMetrics()) {
       this.builtInMetricsProvider.enableGrpcMetrics(
           channelProviderBuilder, this.getProjectId(), getCredentials(), this.monitoringHost);
     }

google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/GapicSpannerRpc.java

@@ -367,8 +367,7 @@ public GapicSpannerRpc(final SpannerOptions options) {
                       .withEncoding(compressorName))
               .setHeaderProvider(headerProviderWithUserAgent)
               .setAllowNonDefaultServiceAccount(true);
-      String directPathXdsEnv = System.getenv("GOOGLE_SPANNER_ENABLE_DIRECT_ACCESS");
-      boolean isAttemptDirectPathXds = Boolean.parseBoolean(directPathXdsEnv);
+      boolean isAttemptDirectPathXds = isEnableDirectPathXdsEnv();
       if (isAttemptDirectPathXds) {
         defaultChannelProviderBuilder.setAttemptDirectPath(true);
         defaultChannelProviderBuilder.setAttemptDirectPathXds();
@@ -678,7 +677,12 @@ private static boolean isEmulatorEnabled(SpannerOptions options, String emulator
   }
 
   public static boolean isEnableAFEServerTiming() {
-    return "false".equalsIgnoreCase(System.getenv("SPANNER_DISABLE_AFE_SERVER_TIMING"));
+    return isEnableDirectPathXdsEnv()
+        || "false".equalsIgnoreCase(System.getenv("SPANNER_DISABLE_AFE_SERVER_TIMING"));
+  }
+
+  public static boolean isEnableDirectPathXdsEnv() {
+    return Boolean.parseBoolean(System.getenv("GOOGLE_SPANNER_ENABLE_DIRECT_ACCESS"));
   }
 
   private static final RetrySettings ADMIN_REQUESTS_LIMIT_EXCEEDED_RETRY_SETTINGS =

google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/HeaderInterceptor.java

@@ -133,7 +133,8 @@ public void onHeaders(Metadata metadata) {
                   Boolean isDirectPathUsed =
                       isDirectPathUsed(getAttributes().get(Grpc.TRANSPORT_ATTR_REMOTE_ADDR));
                   addDirectPathUsedAttribute(compositeTracer, isDirectPathUsed);
-                  processHeader(metadata, tagContext, attributes, span, compositeTracer);
+                  processHeader(
+                      metadata, tagContext, attributes, span, compositeTracer, isDirectPathUsed);
                   super.onHeaders(metadata);
                 }
               },
@@ -151,7 +152,8 @@ private void processHeader(
       TagContext tagContext,
       Attributes attributes,
       Span span,
-      CompositeTracer compositeTracer) {
+      CompositeTracer compositeTracer,
+      boolean isDirectPathUsed) {
     MeasureMap measureMap = STATS_RECORDER.newMeasureMap();
     String serverTiming = metadata.get(SERVER_TIMING_HEADER_KEY);
     try {
@@ -172,7 +174,7 @@ private void processHeader(
 
         spannerRpcMetrics.recordGfeLatency(gfeLatency, attributes);
         spannerRpcMetrics.recordGfeHeaderMissingCount(0L, attributes);
-        if (compositeTracer != null) {
+        if (compositeTracer != null && !isDirectPathUsed) {
           compositeTracer.recordGFELatency(gfeLatency);
         }
         if (span != null) {
@@ -181,7 +183,7 @@ private void processHeader(
       } else {
         measureMap.put(SPANNER_GFE_HEADER_MISSING_COUNT, 1L).record(tagContext);
         spannerRpcMetrics.recordGfeHeaderMissingCount(1L, attributes);
-        if (compositeTracer != null) {
+        if (compositeTracer != null && !isDirectPathUsed) {
           compositeTracer.recordGfeHeaderMissingCount(1L);
         }
       }