io.dapr.internal.grpc.interceptors.DaprMetadataInterceptor Maven / Gradle / Ivy
/*
* Copyright 2024 The Dapr Authors
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
limitations under the License.
*/
package io.dapr.internal.grpc.interceptors;
import io.grpc.CallOptions;
import io.grpc.Channel;
import io.grpc.ClientCall;
import io.grpc.ClientInterceptor;
import io.grpc.ForwardingClientCall;
import io.grpc.ForwardingClientCallListener;
import io.grpc.Metadata;
import io.grpc.MethodDescriptor;
import java.util.function.Consumer;
/**
* Consumes gRPC metadata.
*/
public class DaprMetadataInterceptor implements ClientInterceptor {
private final Consumer metadataConsumer;
/**
* Creates an instance of the consumer for gRPC metadata.
* @param metadataConsumer gRPC metadata consumer
*/
public DaprMetadataInterceptor(Consumer metadataConsumer) {
this.metadataConsumer = metadataConsumer;
}
@Override
public ClientCall interceptCall(
MethodDescriptor methodDescriptor,
CallOptions callOptions,
Channel channel) {
ClientCall clientCall = channel.newCall(methodDescriptor, callOptions);
return new ForwardingClientCall.SimpleForwardingClientCall<>(clientCall) {
@Override
public void start(final Listener responseListener, final Metadata metadata) {
final ClientCall.Listener headerListener =
new ForwardingClientCallListener.SimpleForwardingClientCallListener<>(responseListener) {
@Override
public void onHeaders(Metadata headers) {
responseListener.onHeaders(headers);
if (metadataConsumer != null) {
metadataConsumer.accept(headers);
}
}
};
super.start(headerListener, metadata);
}
};
}
}