add test.

Author: zhumin8

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

@@ -66,7 +66,7 @@ public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
 
       @Override
       public void start(Listener<RespT> responseListener, Metadata headers) {
-        logRequestInfo(method, logDataBuilder);
+        logRequestInfo(method, logDataBuilder, logger);
         recordRequestHeaders(headers, logDataBuilder);
         SimpleForwardingClientCallListener<RespT> responseLoggingListener =
             new SimpleForwardingClientCallListener<RespT>(responseListener) {
@@ -107,7 +107,7 @@ public void sendMessage(ReqT message) {
   // Helper methods for logging
   // some duplications with http equivalent to avoid exposing as public method for now
   <ReqT, RespT> void logRequestInfo(
-      MethodDescriptor<ReqT, RespT> method, LogData.Builder logDataBuilder) {
+      MethodDescriptor<ReqT, RespT> method, LogData.Builder logDataBuilder, Logger logger) {
     try {
       if (logger.isInfoEnabled()) {
         logDataBuilder.serviceName(method.getServiceName()).rpcName(method.getFullMethodName());

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

@@ -30,13 +30,15 @@
 
 package com.google.api.gax.grpc;
 
+import static org.junit.Assert.assertEquals;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import ch.qos.logback.classic.Level;
 import com.google.api.gax.grpc.testing.FakeMethodDescriptor;
 import com.google.api.gax.logging.LogData;
 import io.grpc.CallOptions;
@@ -46,11 +48,14 @@
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 class GrpcLoggingInterceptorTest {
   @Mock private Channel channel;
@@ -59,6 +64,7 @@ class GrpcLoggingInterceptorTest {
 
   private static final MethodDescriptor<String, Integer> method = FakeMethodDescriptor.create();
 
+  private static final Logger LOGGER = LoggerFactory.getLogger(GrpcLoggingInterceptorTest.class);
   /** Sets up mocks. */
   @BeforeEach
   void setUp() {
@@ -111,4 +117,27 @@ void testInterceptor_responseListener() {
     verify(interceptor).recordResponsePayload(any(), any(LogData.Builder.class));
     verify(interceptor).logResponse(eq(status.getCode().toString()), any(LogData.Builder.class));
   }
+
+  @Test
+  void testLogRequestInfo() {
+
+    TestAppender testAppender = setupTestLogger(GrpcLoggingInterceptorTest.class);
+    GrpcLoggingInterceptor interceptor = new GrpcLoggingInterceptor();
+    interceptor.logRequestInfo(method, LogData.builder(), LOGGER);
+
+    Assertions.assertEquals(1, testAppender.events.size());
+    assertEquals(Level.INFO, testAppender.events.get(0).getLevel());
+    assertEquals(
+        "{\"serviceName\":\"FakeClient\",\"message\":\"Sending gRPC request\",\"rpcName\":\"FakeClient/fake-method\"}",
+        testAppender.events.get(0).getMessage());
+    testAppender.stop();
+  }
+
+  private TestAppender setupTestLogger(Class<?> clazz) {
+    TestAppender testAppender = new TestAppender();
+    testAppender.start();
+    Logger logger = LoggerFactory.getLogger(clazz);
+    ((ch.qos.logback.classic.Logger) logger).addAppender(testAppender);
+    return testAppender;
+  }
 }

gax-java/gax-grpc/src/test/java/com/google/api/gax/grpc/TestAppender.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google LLC nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.google.api.gax.grpc;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.AppenderBase;
+import java.util.ArrayList;
+import java.util.List;
+
+/** Logback appender used to set up tests. */
+public class TestAppender extends AppenderBase<ILoggingEvent> {
+  public List<ILoggingEvent> events = new ArrayList<>();
+
+  @Override
+  protected void append(ILoggingEvent eventObject) {
+    // triggering Logback to capture the current MDC context and store it with the log event
+    eventObject.getMDCPropertyMap();
+    events.add(eventObject);
+  }
+
+  public void clearEvents() {
+    events.clear();
+  }
+}

gax-java/gax-grpc/src/test/resources/logback-test.xml

@@ -0,0 +1,6 @@
+<configuration>
+  <appender name="TEST_APPENDER" class="com.google.api.gax.grpc.TestAppender" />
+  <root level="INFO">
+    <appender-ref ref="TEST_APPENDER" />
+  </root>
+</configuration>