fix(gax): unconditionally wrap logging tracer

Author: westarle

gax-java/gax/src/main/java/com/google/api/gax/rpc/ClientContext.java

@@ -281,13 +281,11 @@ public static ClientContext create(StubSettings settings) throws IOException {
     if (apiTracerFactory instanceof SpanTracerFactory) {
       apiTracerFactory = apiTracerFactory.withContext(apiTracerContext);
     }
-    if (com.google.api.gax.logging.LoggingUtils.isLoggingEnabled()) {
-      com.google.api.gax.tracing.ApiTracerFactory loggingTracerFactory =
-          new com.google.api.gax.tracing.LoggingTracerFactory().withContext(apiTracerContext);
-      apiTracerFactory =
-          new com.google.api.gax.tracing.CompositeTracerFactory(
-              apiTracerFactory, loggingTracerFactory);
-    }
+    com.google.api.gax.tracing.ApiTracerFactory loggingTracerFactory =
+        new com.google.api.gax.tracing.LoggingTracerFactory().withContext(apiTracerContext);
+    apiTracerFactory =
+        new com.google.api.gax.tracing.CompositeTracerFactory(
+            apiTracerFactory, loggingTracerFactory);
 
     return newBuilder()
         .setBackgroundResources(backgroundResources.build())

gax-java/gax/src/main/java/com/google/api/gax/tracing/CompositeTracer.java

@@ -52,7 +52,8 @@ public Scope inScope() {
       scopes[i] = tracers.get(i).inScope();
     }
     return () -> {
-      for (Scope scope : scopes) {
+      for (int i = scopes.length - 1; i >= 0; i--) {
+        Scope scope = scopes[i];
         if (scope != null) {
           scope.close();
         }
@@ -62,22 +63,22 @@ public Scope inScope() {
 
   @Override
   public void operationSucceeded() {
-    for (ApiTracer tracer : tracers) {
-      tracer.operationSucceeded();
+    for (int i = tracers.size() - 1; i >= 0; i--) {
+      tracers.get(i).operationSucceeded();
     }
   }
 
   @Override
   public void operationCancelled() {
-    for (ApiTracer tracer : tracers) {
-      tracer.operationCancelled();
+    for (int i = tracers.size() - 1; i >= 0; i--) {
+      tracers.get(i).operationCancelled();
     }
   }
 
   @Override
   public void operationFailed(Throwable error) {
-    for (ApiTracer tracer : tracers) {
-      tracer.operationFailed(error);
+    for (int i = tracers.size() - 1; i >= 0; i--) {
+      tracers.get(i).operationFailed(error);
     }
   }
 

gax-java/gax/src/main/java/com/google/api/gax/tracing/LoggingTracer.java

@@ -116,7 +116,10 @@ private void recordActionableError(Throwable error) {
       }
     }
 
-    String message = error.getMessage() != null ? error.getMessage() : error.getClass().getName();
+    String message = "Unknown Error";
+    if (error != null) {
+      message = error.getMessage() != null ? error.getMessage() : error.getClass().getName();
+    }
     LoggingUtils.logActionableError(logContext, LOGGER_PROVIDER, message);
   }
 }

gax-java/gax/src/test/java/com/google/api/gax/rpc/ClientContextTest.java

@@ -1304,7 +1304,8 @@ void testCreate_withTracerFactoryReturningNullWithContext() throws IOException {
     Mockito.doReturn(apiTracerFactory).when(settings).getTracerFactory();
 
     ClientContext context = ClientContext.create(settings);
-    assertThat(context.getTracerFactory()).isSameInstanceAs(apiTracerFactory);
+    assertThat(context.getTracerFactory())
+        .isInstanceOf(com.google.api.gax.tracing.CompositeTracerFactory.class);
     verify(apiTracerFactory, times(1)).withContext(Mockito.any());
   }
 }