Revert "enable child channel plugins (grpc#12578)"

This reverts commit 89aef90.

Author: AgraVator

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

@@ -242,13 +242,6 @@ public T disableServiceConfigLookUp() {
     return thisT();
   }
 
-
-  @Override
-  public T childChannelConfigurator(ChannelConfigurator channelConfigurator) {
-    delegate().childChannelConfigurator(channelConfigurator);
-    return thisT();
-  }
-
   /**
    * Returns the correctly typed version of the builder.
    */

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

@@ -269,13 +269,6 @@ public <X> T setNameResolverArg(NameResolver.Args.Key<X> key, X value) {
     return thisT();
   }
 
-
-  @Override
-  public T childChannelConfigurator(ChannelConfigurator channelConfigurator) {
-    delegate().childChannelConfigurator(channelConfigurator);
-    return thisT();
-  }
-
   /**
    * Returns the {@link ManagedChannel} built by the delegate by default. Overriding method can
    * return different value.

api/src/main/java/io/grpc/ForwardingChannelBuilder2.java

@@ -666,23 +666,6 @@ public <X> T setNameResolverArg(NameResolver.Args.Key<X> key, X value) {
     throw new UnsupportedOperationException();
   }
 
-
-  /**
-   * Sets a configurator that will be applied to all internal child channels created by this
-   * channel.
-   *
-   * <p>This allows injecting universal configuration (like interceptors)
-   * into auxiliary channels created by gRPC infrastructure, such as xDS control plane connections.
-   *
-   * @param channelConfigurator the configurator to apply.
-   * @return this
-   * @since 1.83.0
-   */
-  @ExperimentalApi("https://github.com/grpc/grpc-java/issues/12574")
-  public T childChannelConfigurator(ChannelConfigurator channelConfigurator) {
-    throw new UnsupportedOperationException("Not implemented");
-  }
-
   /**
    * Builds a channel using the given parameters.
    *

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

@@ -358,7 +358,6 @@ public static final class Args {
     private final MetricRecorder metricRecorder;
     @Nullable private final NameResolverRegistry nameResolverRegistry;
     @Nullable private final IdentityHashMap<Key<?>, Object> customArgs;
-    private final ChannelConfigurator channelConfigurator;
 
     private Args(Builder builder) {
       this.defaultPort = checkNotNull(builder.defaultPort, "defaultPort not set");
@@ -374,7 +373,6 @@ private Args(Builder builder) {
           : new MetricRecorder() {};
       this.nameResolverRegistry = builder.nameResolverRegistry;
       this.customArgs = cloneCustomArgs(builder.customArgs);
-      this.channelConfigurator = builder.channelConfigurator;
     }
 
     /**
@@ -473,16 +471,6 @@ public ChannelLogger getChannelLogger() {
       return channelLogger;
     }
 
-    /**
-     * Returns the configurator for child channels.
-     *
-     * @since 1.83.0
-     */
-    @ExperimentalApi("https://github.com/grpc/grpc-java/issues/12574")
-    public ChannelConfigurator getChildChannelConfigurator() {
-      return channelConfigurator;
-    }
-
     /**
      * Returns the Executor on which this resolver should execute long-running or I/O bound work.
      * Null if no Executor was set.
@@ -561,7 +549,6 @@ public Builder toBuilder() {
       builder.setOverrideAuthority(overrideAuthority);
       builder.setMetricRecorder(metricRecorder);
       builder.setNameResolverRegistry(nameResolverRegistry);
-      builder.setChildChannelConfigurator(channelConfigurator);
       builder.customArgs = cloneCustomArgs(customArgs);
       return builder;
     }
@@ -592,7 +579,6 @@ public static final class Builder {
       private MetricRecorder metricRecorder;
       private NameResolverRegistry nameResolverRegistry;
       private IdentityHashMap<Key<?>, Object> customArgs;
-      private ChannelConfigurator channelConfigurator = builder -> { };
 
       Builder() {
       }
@@ -708,17 +694,6 @@ public Builder setNameResolverRegistry(NameResolverRegistry registry) {
         return this;
       }
 
-      /**
-       * See {@link Args#getChildChannelConfigurator()}. This is an optional field.
-       *
-       * @since 1.83.0
-       */
-      @ExperimentalApi("https://github.com/grpc/grpc-java/issues/12574")
-      public Builder setChildChannelConfigurator(ChannelConfigurator channelConfigurator) {
-        this.channelConfigurator = checkNotNull(channelConfigurator, "channelConfigurator");
-        return this;
-      }
-
       /**
        * Builds an {@link Args}.
        *

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

@@ -22,7 +22,6 @@
 import static org.mockito.Mockito.verify;
 
 import com.google.common.base.Objects;
-import io.grpc.ChannelConfigurator;
 import io.grpc.NameResolver.ConfigOrError;
 import io.grpc.NameResolver.Listener2;
 import io.grpc.NameResolver.ResolutionResult;
@@ -73,8 +72,6 @@ public class NameResolverTest {
   private final int customArgValue = 42;
   @Mock NameResolver.Listener mockListener;
 
-  private final ChannelConfigurator channelConfigurator = builder -> { };
-
   @Test
   public void args() {
     NameResolver.Args args = createArgs();
@@ -87,7 +84,6 @@ public void args() {
     assertThat(args.getOffloadExecutor()).isSameInstanceAs(executor);
     assertThat(args.getOverrideAuthority()).isSameInstanceAs(overrideAuthority);
     assertThat(args.getMetricRecorder()).isSameInstanceAs(metricRecorder);
-    assertThat(args.getChildChannelConfigurator()).isSameInstanceAs(channelConfigurator);
     assertThat(args.getArg(FOO_ARG_KEY)).isEqualTo(customArgValue);
     assertThat(args.getArg(BAR_ARG_KEY)).isNull();
 
@@ -101,7 +97,6 @@ public void args() {
     assertThat(args2.getOffloadExecutor()).isSameInstanceAs(executor);
     assertThat(args2.getOverrideAuthority()).isSameInstanceAs(overrideAuthority);
     assertThat(args.getMetricRecorder()).isSameInstanceAs(metricRecorder);
-    assertThat(args2.getChildChannelConfigurator()).isSameInstanceAs(channelConfigurator);
     assertThat(args.getArg(FOO_ARG_KEY)).isEqualTo(customArgValue);
     assertThat(args.getArg(BAR_ARG_KEY)).isNull();
 
@@ -120,47 +115,10 @@ private NameResolver.Args createArgs() {
         .setOffloadExecutor(executor)
         .setOverrideAuthority(overrideAuthority)
         .setMetricRecorder(metricRecorder)
-        .setChildChannelConfigurator(channelConfigurator)
         .setArg(FOO_ARG_KEY, customArgValue)
         .build();
   }
 
-  @Test
-  public void args_childChannelConfigurator() {
-    final ManagedChannelBuilder<?>[] capturedBuilder = new ManagedChannelBuilder<?>[1];
-    ChannelConfigurator channelConfigurator = new ChannelConfigurator() {
-      @Override
-      public void configureChannelBuilder(ManagedChannelBuilder<?> builder) {
-        capturedBuilder[0] = builder;
-      }
-    };
-
-    SynchronizationContext realSyncContext = new SynchronizationContext(
-        new Thread.UncaughtExceptionHandler() {
-          @Override
-          public void uncaughtException(Thread t, Throwable e) {
-            throw new AssertionError(e);
-          }
-        });
-
-    NameResolver.Args args = NameResolver.Args.newBuilder()
-        .setDefaultPort(8080)
-        .setProxyDetector(mock(ProxyDetector.class))
-        .setSynchronizationContext(realSyncContext)
-        .setServiceConfigParser(mock(NameResolver.ServiceConfigParser.class))
-        .setChannelLogger(mock(ChannelLogger.class))
-        .setChildChannelConfigurator(channelConfigurator)
-        .build();
-
-    ChannelConfigurator configurator = args.getChildChannelConfigurator();
-    assertThat(configurator).isSameInstanceAs(channelConfigurator);
-    
-    // Validate configurator accepts builders
-    ManagedChannelBuilder<?> mockBuilder = mock(ManagedChannelBuilder.class);
-    configurator.configureChannelBuilder(mockBuilder);
-    assertThat(capturedBuilder[0]).isSameInstanceAs(mockBuilder);
-  }
-
   @Test
   @SuppressWarnings("deprecation")
   public void startOnOldListener_wrapperListener2UsedToStart() {

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

@@ -37,7 +37,6 @@
 import io.grpc.CallCredentials;
 import io.grpc.CallOptions;
 import io.grpc.Channel;
-import io.grpc.ChannelConfigurator;
 import io.grpc.ChannelCredentials;
 import io.grpc.ChannelLogger;
 import io.grpc.ChannelLogger.ChannelLogLevel;
@@ -156,14 +155,6 @@ public Result selectConfig(PickSubchannelArgs args) {
   private static final LoadBalancer.PickDetailsConsumer NOOP_PICK_DETAILS_CONSUMER =
       new LoadBalancer.PickDetailsConsumer() {};
 
-  /**
-   * Retrieves the user-provided configuration function for internal child channels.
-   *
-   * <p>This is intended for use by gRPC internal components
-   * that are responsible for creating auxiliary {@code ManagedChannel} instances.
-   */
-  private final ChannelConfigurator channelConfigurator;
-
   private final InternalLogId logId;
   private final String target;
   @Nullable
@@ -554,8 +545,6 @@ ClientStream newSubstream(
       Supplier<Stopwatch> stopwatchSupplier,
       List<ClientInterceptor> interceptors,
       final TimeProvider timeProvider) {
-    this.channelConfigurator = checkNotNull(builder.channelConfigurator,
-            "channelConfigurator");
     this.target = checkNotNull(builder.target, "target");
     this.logId = InternalLogId.allocate("Channel", target);
     this.timeProvider = checkNotNull(timeProvider, "timeProvider");
@@ -600,8 +589,7 @@ ClientStream newSubstream(
             .setOffloadExecutor(this.offloadExecutorHolder)
             .setOverrideAuthority(this.authorityOverride)
             .setMetricRecorder(this.metricRecorder)
-            .setNameResolverRegistry(builder.nameResolverRegistry)
-            .setChildChannelConfigurator(this.channelConfigurator);
+            .setNameResolverRegistry(builder.nameResolverRegistry);
     builder.copyAllNameResolverCustomArgsTo(nameResolverArgsBuilder);
     this.nameResolverArgs = nameResolverArgsBuilder.build();
     this.nameResolver = getNameResolver(
@@ -1501,11 +1489,6 @@ protected ManagedChannelBuilder<?> delegate() {
 
       ResolvingOobChannelBuilder builder = new ResolvingOobChannelBuilder();
 
-      // Note that we follow the global configurator pattern and try to fuse the configurations as
-      // soon as the builder gets created
-      channelConfigurator.configureChannelBuilder(builder);
-      builder.childChannelConfigurator(channelConfigurator);
-
       return builder
           // TODO(zdapeng): executors should not outlive the parent channel.
           .executor(executor)

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

@@ -29,7 +29,6 @@
 import io.grpc.CallCredentials;
 import io.grpc.CallOptions;
 import io.grpc.Channel;
-import io.grpc.ChannelConfigurator;
 import io.grpc.ChannelCredentials;
 import io.grpc.ClientCall;
 import io.grpc.ClientInterceptor;
@@ -150,8 +149,6 @@ public static ManagedChannelBuilder<?> forTarget(String target) {
   }
 
 
-  ChannelConfigurator channelConfigurator = builder -> { };
-
   ObjectPool<? extends Executor> executorPool = DEFAULT_EXECUTOR_POOL;
 
   ObjectPool<? extends Executor> offloadExecutorPool = DEFAULT_EXECUTOR_POOL;
@@ -759,14 +756,6 @@ protected ManagedChannelImplBuilder addMetricSink(MetricSink metricSink) {
     return this;
   }
 
-  @Override
-  public ManagedChannelImplBuilder childChannelConfigurator(
-      ChannelConfigurator channelConfigurator) {
-    this.channelConfigurator = checkNotNull(channelConfigurator,
-        "childChannelConfigurator");
-    return this;
-  }
-
   @Override
   public ManagedChannel build() {
     ClientTransportFactory clientTransportFactory =