io.dapr.internal.grpc.interceptors.DaprTracingInterceptor 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.dapr.internal.opencensus.GrpcHelper;
import io.grpc.CallOptions;
import io.grpc.Channel;
import io.grpc.ClientCall;
import io.grpc.ClientInterceptor;
import io.grpc.ForwardingClientCall;
import io.grpc.Metadata;
import io.grpc.MethodDescriptor;
import reactor.util.context.ContextView;
/**
* Injects tracing headers to gRPC metadata.
*/
public class DaprTracingInterceptor implements ClientInterceptor {
private final ContextView context;
/**
* Creates an instance of the injector for gRPC context from Reactor's context.
* @param context Reactor's context
*/
public DaprTracingInterceptor(ContextView context) {
this.context = context;
}
@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) {
if (context != null) {
GrpcHelper.populateMetadata(context, metadata);
}
super.start(responseListener, metadata);
}
};
}
}