content: /*
   * 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.arrow.flight.auth2;
  
  import org.apache.arrow.flight.CallHeaders;
  import org.apache.arrow.flight.CallInfo;
  import org.apache.arrow.flight.CallStatus;
  import org.apache.arrow.flight.FlightClientMiddleware;
  import org.apache.arrow.flight.grpc.CredentialCallOption;
  
  /** Middleware for capturing bearer tokens sent back from the Flight server. */
  public class ClientIncomingAuthHeaderMiddleware implements FlightClientMiddleware {
    private final Factory factory;
  
    /** Factory used within FlightClient. */
    public static class Factory implements FlightClientMiddleware.Factory {
      private final ClientHeaderHandler headerHandler;
      private CredentialCallOption credentialCallOption = null;
  
      /**
       * Construct a factory with the given header handler.
       *
       * @param headerHandler The header handler that will be used for handling incoming headers from
       *     the flight server.
       */
      public Factory(ClientHeaderHandler headerHandler) {
        this.headerHandler = headerHandler;
      }
  
      @Override
      public FlightClientMiddleware onCallStarted(CallInfo info) {
        return new ClientIncomingAuthHeaderMiddleware(this);
      }
  
      void setCredentialCallOption(CredentialCallOption callOption) {
        this.credentialCallOption = callOption;
      }
  
      public CredentialCallOption getCredentialCallOption() {
        return credentialCallOption;
      }
    }
  
    private ClientIncomingAuthHeaderMiddleware(Factory factory) {
      this.factory = factory;
    }
  
    @Override
    public void onBeforeSendingHeaders(CallHeaders outgoingHeaders) {}
  
    @Override
    public void onHeadersReceived(CallHeaders incomingHeaders) {
      factory.setCredentialCallOption(
          factory.headerHandler.getCredentialCallOptionFromIncomingHeaders(incomingHeaders));
    }
  
    @Override
    public void onCallCompleted(CallStatus status) {}
  }
  