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.camel.component.grpc.auth.jwt;
  
  import java.util.concurrent.Executor;
  
  import io.grpc.CallCredentials;
  import io.grpc.Metadata;
  import io.grpc.Status;
  import org.apache.camel.component.grpc.GrpcConstants;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * JSON Web Token client credentials generator and injector
   */
  public class JwtCallCredentials extends CallCredentials {
      private static final Logger LOG = LoggerFactory.getLogger(JwtCallCredentials.class);
      private final String jwtToken;
  
      public JwtCallCredentials(String jwtToken) {
          this.jwtToken = jwtToken;
      }
  
      @Override
      public void applyRequestMetadata(RequestInfo requestInfo, Executor executor, MetadataApplier metadataApplier) {
          String authority = requestInfo.getAuthority();
  
          LOG.debug("Using authority {} for credentials", authority);
          executor.execute(() -> {
              try {
                  LOG.debug("Start to apply for the JWT token header");
                  Metadata headers = new Metadata();
                  Metadata.Key<String> jwtKey = GrpcConstants.GRPC_JWT_METADATA_KEY;
                  headers.put(jwtKey, jwtToken);
                  metadataApplier.apply(headers);
              } catch (Exception e) {
                  LOG.debug("Unable to set metadata credentials header", e);
                  metadataApplier.fail(Status.UNAUTHENTICATED.withCause(e));
              }
          });
      }
  
      @Override
      public void thisUsesUnstableApi() {
      }
  }
  