hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/ClientCredentialInterceptor.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.hadoop.hdds.scm;

import org.apache.ratis.thirdparty.io.grpc.CallOptions;
import org.apache.ratis.thirdparty.io.grpc.Channel;
import org.apache.ratis.thirdparty.io.grpc.ClientCall;
import org.apache.ratis.thirdparty.io.grpc.ClientInterceptor;
import org.apache.ratis.thirdparty.io.grpc.ForwardingClientCall;
import org.apache.ratis.thirdparty.io.grpc.Metadata;
import org.apache.ratis.thirdparty.io.grpc.MethodDescriptor;

import static org.apache.hadoop.ozone.OzoneConsts.OBT_METADATA_KEY;
import static org.apache.hadoop.ozone.OzoneConsts.USER_METADATA_KEY;

/**
 * GRPC client interceptor for ozone block token.
 */
public class ClientCredentialInterceptor implements ClientInterceptor {

  private final String user;
  private final String token;

  public ClientCredentialInterceptor(String user, String token) {
    this.user = user;
    this.token = token;
  }

  @Override
  public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
      MethodDescriptor<ReqT, RespT> method,
      CallOptions callOptions,
      Channel next) {

    return new ForwardingClientCall.SimpleForwardingClientCall<ReqT, RespT>(
        next.newCall(method, callOptions)) {
      @Override
      public void start(Listener<RespT> responseListener, Metadata headers) {
        if (token != null) {
          headers.put(OBT_METADATA_KEY, token);
        }
        if (user != null) {
          headers.put(USER_METADATA_KEY, user);
        }
        super.start(responseListener, headers);
      }
    };
  }
}