perf(gax-grpc): skip metadata materialization when logging is disabled

Author: rahul2393

sdk-platform-java/gax-java/gax-grpc/src/main/java/com/google/api/gax/grpc/GrpcLoggingInterceptor.java

@@ -31,6 +31,7 @@
 package com.google.api.gax.grpc;
 
 import static com.google.api.gax.logging.LoggingUtils.executeWithTryCatch;
+import static com.google.api.gax.logging.LoggingUtils.isLoggingEnabled;
 import static com.google.api.gax.logging.LoggingUtils.logRequest;
 import static com.google.api.gax.logging.LoggingUtils.logResponse;
 import static com.google.api.gax.logging.LoggingUtils.recordResponseHeaders;
@@ -70,19 +71,23 @@ public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
 
       @Override
       public void start(Listener<RespT> responseListener, Metadata headers) {
-        recordServiceRpcAndRequestHeaders(
-            method.getServiceName(),
-            method.getFullMethodName(),
-            null, // endpoint is for http request only
-            metadataHeadersToMap(headers),
-            logDataBuilder,
-            LOGGER_PROVIDER);
+        if (isLoggingEnabled()) {
+          recordServiceRpcAndRequestHeaders(
+              method.getServiceName(),
+              method.getFullMethodName(),
+              null, // endpoint is for http request only
+              metadataHeadersToMap(headers),
+              logDataBuilder,
+              LOGGER_PROVIDER);
+        }
         SimpleForwardingClientCallListener<RespT> responseLoggingListener =
             new SimpleForwardingClientCallListener<RespT>(responseListener) {
               @Override
               public void onHeaders(Metadata headers) {
-                recordResponseHeaders(
-                    metadataHeadersToMap(headers), logDataBuilder, LOGGER_PROVIDER);
+                if (isLoggingEnabled()) {
+                  recordResponseHeaders(
+                      metadataHeadersToMap(headers), logDataBuilder, LOGGER_PROVIDER);
+                }
                 super.onHeaders(headers);
               }
 

sdk-platform-java/gax-java/gax-grpc/src/test/java/com/google/api/gax/grpc/GrpcLoggingInterceptorTest.java

@@ -30,6 +30,7 @@
 
 package com.google.api.gax.grpc;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
@@ -44,6 +45,8 @@
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
+import java.lang.reflect.Method;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
@@ -58,6 +61,11 @@ class GrpcLoggingInterceptorTest {
 
   private static final MethodDescriptor<String, Integer> method = FakeMethodDescriptor.create();
 
+  @AfterEach
+  void tearDown() throws Exception {
+    setLoggingEnabled(false);
+  }
+
   @Test
   void testInterceptor_basic() {
     when(channel.newCall(Mockito.<MethodDescriptor<String, Integer>>any(), any(CallOptions.class)))
@@ -101,4 +109,36 @@ void testInterceptor_responseListener() {
     Status status = Status.OK;
     interceptor.currentListener.onClose(status, new Metadata());
   }
+
+  @Test
+  void testInterceptor_skipsMetadataMaterializationWhenLoggingDisabled() throws Exception {
+    setLoggingEnabled(false);
+    when(channel.newCall(Mockito.<MethodDescriptor<String, Integer>>any(), any(CallOptions.class)))
+        .thenReturn(call);
+
+    GrpcLoggingInterceptor interceptor = new GrpcLoggingInterceptor();
+    Channel intercepted = ClientInterceptors.intercept(channel, interceptor);
+
+    @SuppressWarnings("unchecked")
+    ClientCall.Listener<Integer> listener = mock(ClientCall.Listener.class);
+
+    Metadata requestHeaders = mock(Metadata.class);
+    when(requestHeaders.keys()).thenThrow(new AssertionError("request headers should not be read"));
+    ClientCall<String, Integer> interceptedCall = intercepted.newCall(method, CallOptions.DEFAULT);
+
+    assertDoesNotThrow(() -> interceptedCall.start(listener, requestHeaders));
+
+    Metadata responseHeaders = mock(Metadata.class);
+    when(responseHeaders.keys())
+        .thenThrow(new AssertionError("response headers should not be read"));
+
+    assertDoesNotThrow(() -> interceptor.currentListener.onHeaders(responseHeaders));
+  }
+
+  private static void setLoggingEnabled(boolean enabled) throws Exception {
+    Class<?> loggingUtils = Class.forName("com.google.api.gax.logging.LoggingUtils");
+    Method method = loggingUtils.getDeclaredMethod("setLoggingEnabled", boolean.class);
+    method.setAccessible(true);
+    method.invoke(null, enabled);
+  }
 }