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 com.alibaba.cloudapp.apigateway.aliyun.interceptor;
  
  import com.alibaba.cloudapp.api.gateway.authentication.APIKeyAuthorizer;
  import com.alibaba.cloudapp.api.gateway.authentication.Authorizer;
  import com.alibaba.cloudapp.exeption.CloudAppException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.http.HttpHeaders;
  import org.springframework.http.HttpRequest;
  import org.springframework.http.client.ClientHttpRequestExecution;
  import org.springframework.http.client.ClientHttpRequestInterceptor;
  import org.springframework.http.client.ClientHttpResponse;
  
  import java.io.IOException;
  
  public class AuthorizationInterceptor implements ClientHttpRequestInterceptor {
  
      private static final Logger logger = LoggerFactory.getLogger(
              AuthorizationInterceptor.class);
  
      private final Authorizer authorizer;
  
      public AuthorizationInterceptor(Authorizer authorizer) {
          this.authorizer = authorizer;
      }
  
      @Override
      public ClientHttpResponse intercept(
              HttpRequest request,
              byte[] body,
              ClientHttpRequestExecution execution) throws IOException {
  
          // apply authorization
          try {
              String headerName = HttpHeaders.AUTHORIZATION;
              if(authorizer instanceof APIKeyAuthorizer) {
                  headerName = ((APIKeyAuthorizer) authorizer).getHeaderName();
              } else {
                  if (logger.isDebugEnabled()) {
                      logger.debug("The authorizer is not APIKeyAuthorizer");
                  }
              }
  
              if (!request.getHeaders().containsKey(headerName)) {
                  authorizer.applyAuthorization(request);
              } else {
                  if (logger.isDebugEnabled()) {
                      logger.debug("The request already contains the header: {}", headerName);
                  }
              }
          } catch (CloudAppException e) {
              throw new RuntimeException("Failed to apply authorization", e);
          }
  
          return execution.execute(request, body);
      }
  }
  