api,core: change ManagedChannel and Server Builders to use GlobalInte…

…rceptors (#9312)

* api,core: change ManagedChannel and Server Builders to use GlobalInterceptors
also added a getter in GlobalInterceptors to expose the set flag

api/src/main/java/io/grpc/GlobalInterceptors.java

@@ -16,17 +16,19 @@
 
 package io.grpc;
 
+import static com.google.common.base.Preconditions.checkNotNull;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
 /** The collection of global interceptors and global server stream tracers. */
 @Internal
 final class GlobalInterceptors {
-  private static List<ClientInterceptor> clientInterceptors = Collections.emptyList();
-  private static List<ServerInterceptor> serverInterceptors = Collections.emptyList();
+  private static List<ClientInterceptor> clientInterceptors = null;
+  private static List<ServerInterceptor> serverInterceptors = null;
   private static List<ServerStreamTracer.Factory> serverStreamTracerFactories =
-      Collections.emptyList();
+      null;
   private static boolean isGlobalInterceptorsTracersSet;
   private static boolean isGlobalInterceptorsTracersGet;
 
@@ -61,19 +63,13 @@ static synchronized void setInterceptorsTracers(
     if (isGlobalInterceptorsTracersSet) {
       throw new IllegalStateException("Global interceptors and tracers are already set");
     }
-
-    if (clientInterceptorList != null) {
-      clientInterceptors = Collections.unmodifiableList(new ArrayList<>(clientInterceptorList));
-    }
-
-    if (serverInterceptorList != null) {
-      serverInterceptors = Collections.unmodifiableList(new ArrayList<>(serverInterceptorList));
-    }
-
-    if (serverStreamTracerFactoryList != null) {
-      serverStreamTracerFactories =
+    checkNotNull(clientInterceptorList);
+    checkNotNull(serverInterceptorList);
+    checkNotNull(serverStreamTracerFactoryList);
+    clientInterceptors = Collections.unmodifiableList(new ArrayList<>(clientInterceptorList));
+    serverInterceptors = Collections.unmodifiableList(new ArrayList<>(serverInterceptorList));
+    serverStreamTracerFactories =
           Collections.unmodifiableList(new ArrayList<>(serverStreamTracerFactoryList));
-    }
     isGlobalInterceptorsTracersSet = true;
   }
 

api/src/test/java/io/grpc/GlobalInterceptorsTest.java

@@ -21,6 +21,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.regex.Pattern;
 import org.junit.Test;
@@ -98,7 +99,7 @@ public static final class StaticTestingClassLoaderSetTwice implements Runnable {
     public void run() {
       GlobalInterceptors.setInterceptorsTracers(
           new ArrayList<>(Arrays.asList(new NoopClientInterceptor())),
-          null,
+              Collections.emptyList(),
           new ArrayList<>(Arrays.asList(new NoopServerStreamTracerFactory())));
       try {
         GlobalInterceptors.setInterceptorsTracers(
@@ -115,7 +116,7 @@ public static final class StaticTestingClassLoaderGetBeforeSetClientInterceptor
     @Override
     public void run() {
       List<ClientInterceptor> clientInterceptors = GlobalInterceptors.getClientInterceptors();
-      assertThat(clientInterceptors).isEmpty();
+      assertThat(clientInterceptors).isNull();
 
       try {
         GlobalInterceptors.setInterceptorsTracers(
@@ -132,7 +133,7 @@ public static final class StaticTestingClassLoaderGetBeforeSetServerInterceptor
     @Override
     public void run() {
       List<ServerInterceptor> serverInterceptors = GlobalInterceptors.getServerInterceptors();
-      assertThat(serverInterceptors).isEmpty();
+      assertThat(serverInterceptors).isNull();
 
       try {
         GlobalInterceptors.setInterceptorsTracers(
@@ -150,7 +151,7 @@ public static final class StaticTestingClassLoaderGetBeforeSetServerStreamTracer
     public void run() {
       List<ServerStreamTracer.Factory> serverStreamTracerFactories =
           GlobalInterceptors.getServerStreamTracerFactories();
-      assertThat(serverStreamTracerFactories).isEmpty();
+      assertThat(serverStreamTracerFactories).isNull();
 
       try {
         GlobalInterceptors.setInterceptorsTracers(

core/src/main/java/io/grpc/internal/ManagedChannelImplBuilder.java

@@ -31,6 +31,7 @@
 import io.grpc.DecompressorRegistry;
 import io.grpc.EquivalentAddressGroup;
 import io.grpc.InternalChannelz;
+import io.grpc.InternalGlobalInterceptors;
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
 import io.grpc.NameResolver;
@@ -636,9 +637,15 @@ public ManagedChannel build() {
   // TODO(zdapeng): FIX IT
   @VisibleForTesting
   List<ClientInterceptor> getEffectiveInterceptors() {
-    List<ClientInterceptor> effectiveInterceptors =
-        new ArrayList<>(this.interceptors);
-    if (statsEnabled) {
+    List<ClientInterceptor> effectiveInterceptors = new ArrayList<>(this.interceptors);
+    boolean isGlobalInterceptorsSet = false;
+    List<ClientInterceptor> globalClientInterceptors =
+        InternalGlobalInterceptors.getClientInterceptors();
+    if (globalClientInterceptors != null) {
+      effectiveInterceptors.addAll(globalClientInterceptors);
+      isGlobalInterceptorsSet = true;
+    }
+    if (!isGlobalInterceptorsSet && statsEnabled) {
       ClientInterceptor statsInterceptor = null;
       try {
         Class<?> censusStatsAccessor =
@@ -674,7 +681,7 @@ List<ClientInterceptor> getEffectiveInterceptors() {
         effectiveInterceptors.add(0, statsInterceptor);
       }
     }
-    if (tracingEnabled) {
+    if (!isGlobalInterceptorsSet && tracingEnabled) {
       ClientInterceptor tracingInterceptor = null;
       try {
         Class<?> censusTracingAccessor =

core/src/main/java/io/grpc/internal/ServerImplBuilder.java

@@ -30,6 +30,7 @@
 import io.grpc.DecompressorRegistry;
 import io.grpc.HandlerRegistry;
 import io.grpc.InternalChannelz;
+import io.grpc.InternalGlobalInterceptors;
 import io.grpc.Server;
 import io.grpc.ServerBuilder;
 import io.grpc.ServerCallExecutorSupplier;
@@ -246,7 +247,17 @@ public Server build() {
   @VisibleForTesting
   List<? extends ServerStreamTracer.Factory> getTracerFactories() {
     ArrayList<ServerStreamTracer.Factory> tracerFactories = new ArrayList<>();
-    if (statsEnabled) {
+    boolean isGlobalInterceptorsTracersSet = false;
+    List<ServerInterceptor> globalServerInterceptors
+        = InternalGlobalInterceptors.getServerInterceptors();
+    List<ServerStreamTracer.Factory> globalServerStreamTracerFactories
+        = InternalGlobalInterceptors.getServerStreamTracerFactories();
+    if (globalServerInterceptors != null) {
+      tracerFactories.addAll(globalServerStreamTracerFactories);
+      interceptors.addAll(globalServerInterceptors);
+      isGlobalInterceptorsTracersSet = true;
+    }
+    if (!isGlobalInterceptorsTracersSet && statsEnabled) {
       ServerStreamTracer.Factory censusStatsTracerFactory = null;
       try {
         Class<?> censusStatsAccessor =
@@ -278,7 +289,7 @@ List<? extends ServerStreamTracer.Factory> getTracerFactories() {
         tracerFactories.add(censusStatsTracerFactory);
       }
     }
-    if (tracingEnabled) {
+    if (!isGlobalInterceptorsTracersSet && tracingEnabled) {
       ServerStreamTracer.Factory tracingStreamTracerFactory = null;
       try {
         Class<?> censusTracingAccessor =

core/src/test/java/io/grpc/internal/ManagedChannelImplBuilderTest.java

@@ -35,9 +35,11 @@
 import io.grpc.ClientInterceptor;
 import io.grpc.CompressorRegistry;
 import io.grpc.DecompressorRegistry;
+import io.grpc.InternalGlobalInterceptors;
 import io.grpc.ManagedChannel;
 import io.grpc.MethodDescriptor;
 import io.grpc.NameResolver;
+import io.grpc.StaticTestingClassLoader;
 import io.grpc.internal.ManagedChannelImplBuilder.ChannelBuilderDefaultPortProvider;
 import io.grpc.internal.ManagedChannelImplBuilder.ClientTransportFactoryBuilder;
 import io.grpc.internal.ManagedChannelImplBuilder.FixedPortProvider;
@@ -47,12 +49,14 @@
 import java.net.SocketAddress;
 import java.net.URI;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -78,6 +82,14 @@ public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
           return next.newCall(method, callOptions);
         }
       };
+  private static final ClientInterceptor DUMMY_USER_INTERCEPTOR1 =
+      new ClientInterceptor() {
+        @Override
+        public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
+            MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {
+          return next.newCall(method, callOptions);
+        }
+      };
 
   @Rule public final MockitoRule mocks = MockitoJUnit.rule();
   @SuppressWarnings("deprecation") // https://github.com/grpc/grpc-java/issues/7467
@@ -90,7 +102,12 @@ public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
   private ManagedChannelImplBuilder builder;
   private ManagedChannelImplBuilder directAddressBuilder;
   private final FakeClock clock = new FakeClock();
-
+  private final StaticTestingClassLoader classLoader =
+      new StaticTestingClassLoader(
+          getClass().getClassLoader(),
+          Pattern.compile(
+              "io\\.grpc\\.InternalGlobalInterceptors|io\\.grpc\\.GlobalInterceptors|"
+                  + "io\\.grpc\\.internal\\.[^.]+"));
 
   @Before
   public void setUp() throws Exception {
@@ -447,6 +464,86 @@ public void getEffectiveInterceptors_disableBoth() {
     assertThat(effectiveInterceptors).containsExactly(DUMMY_USER_INTERCEPTOR);
   }
 
+  @Test
+  public void getEffectiveInterceptors_callsGetGlobalInterceptors() throws Exception {
+    Class<?> runnable = classLoader.loadClass(StaticTestingClassLoaderCallsGet.class.getName());
+    ((Runnable) runnable.getDeclaredConstructor().newInstance()).run();
+  }
+
+  // UsedReflectively
+  public static final class StaticTestingClassLoaderCallsGet implements Runnable {
+
+    @Override
+    public void run() {
+      ManagedChannelImplBuilder builder =
+          new ManagedChannelImplBuilder(
+              DUMMY_TARGET,
+              new UnsupportedClientTransportFactoryBuilder(),
+              new FixedPortProvider(DUMMY_PORT));
+      List<ClientInterceptor> effectiveInterceptors = builder.getEffectiveInterceptors();
+      assertThat(effectiveInterceptors).hasSize(2);
+      try {
+        InternalGlobalInterceptors.setInterceptorsTracers(
+            Arrays.asList(DUMMY_USER_INTERCEPTOR),
+            Collections.emptyList(),
+            Collections.emptyList());
+        fail("exception expected");
+      } catch (IllegalStateException e) {
+        assertThat(e).hasMessageThat().contains("Set cannot be called after any get call");
+      }
+    }
+  }
+
+  @Test
+  public void getEffectiveInterceptors_callsSetGlobalInterceptors() throws Exception {
+    Class<?> runnable = classLoader.loadClass(StaticTestingClassLoaderCallsSet.class.getName());
+    ((Runnable) runnable.getDeclaredConstructor().newInstance()).run();
+  }
+
+  // UsedReflectively
+  public static final class StaticTestingClassLoaderCallsSet implements Runnable {
+
+    @Override
+    public void run() {
+      InternalGlobalInterceptors.setInterceptorsTracers(
+          Arrays.asList(DUMMY_USER_INTERCEPTOR, DUMMY_USER_INTERCEPTOR1),
+          Collections.emptyList(),
+          Collections.emptyList());
+      ManagedChannelImplBuilder builder =
+          new ManagedChannelImplBuilder(
+              DUMMY_TARGET,
+              new UnsupportedClientTransportFactoryBuilder(),
+              new FixedPortProvider(DUMMY_PORT));
+      List<ClientInterceptor> effectiveInterceptors = builder.getEffectiveInterceptors();
+      assertThat(effectiveInterceptors)
+          .containsExactly(DUMMY_USER_INTERCEPTOR, DUMMY_USER_INTERCEPTOR1);
+    }
+  }
+
+  @Test
+  public void getEffectiveInterceptors_setEmptyGlobalInterceptors() throws Exception {
+    Class<?> runnable =
+        classLoader.loadClass(StaticTestingClassLoaderCallsSetEmpty.class.getName());
+    ((Runnable) runnable.getDeclaredConstructor().newInstance()).run();
+  }
+
+  // UsedReflectively
+  public static final class StaticTestingClassLoaderCallsSetEmpty implements Runnable {
+
+    @Override
+    public void run() {
+      InternalGlobalInterceptors.setInterceptorsTracers(
+          Collections.emptyList(), Collections.emptyList(), Collections.emptyList());
+      ManagedChannelImplBuilder builder =
+          new ManagedChannelImplBuilder(
+              DUMMY_TARGET,
+              new UnsupportedClientTransportFactoryBuilder(),
+              new FixedPortProvider(DUMMY_PORT));
+      List<ClientInterceptor> effectiveInterceptors = builder.getEffectiveInterceptors();
+      assertThat(effectiveInterceptors).isEmpty();
+    }
+  }
+
   @Test
   public void idleTimeout() {
     assertEquals(ManagedChannelImplBuilder.IDLE_MODE_DEFAULT_TIMEOUT_MILLIS,