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.ambari.server.api.services.views;
  
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.Map;
  
  import jakarta.ws.rs.GET;
  import jakarta.ws.rs.Path;
  import jakarta.ws.rs.PathParam;
  import jakarta.ws.rs.Produces;
  import jakarta.ws.rs.core.Context;
  import jakarta.ws.rs.core.HttpHeaders;
  import jakarta.ws.rs.core.Response;
  import jakarta.ws.rs.core.UriInfo;
  
  import org.apache.ambari.annotations.ApiIgnore;
  import org.apache.ambari.server.api.resources.ResourceInstance;
  import org.apache.ambari.server.api.services.BaseService;
  import org.apache.ambari.server.api.services.Request;
  import org.apache.ambari.server.controller.spi.Resource;
  import org.apache.ambari.server.orm.entities.ViewEntity;
  import org.apache.ambari.server.orm.entities.ViewInstanceEntity;
  
  /**
   * Service responsible for view sub-resource requests.
   */
  public class ViewExternalSubResourceService  extends BaseService {
  
    /**
     * The resource type.
     */
    private final Resource.Type type;
  
    /**
     * The view name.
     */
    private final String viewName;
  
    /**
     * The view version.
     */
    private final String version;
  
    /**
     * The instance name.
     */
    private final String instanceName;
  
    /**
     * Mapping of resource names to services.
     */
    private final Map<String, Object> resourceServiceMap = new HashMap<>();
  
    // ----- Constructors ------------------------------------------------------
  
    public ViewExternalSubResourceService(Resource.Type type, ViewInstanceEntity viewInstanceDefinition) {
      ViewEntity viewEntity = viewInstanceDefinition.getViewEntity();
  
      this.type         = type;
      this.viewName     = viewEntity.getCommonName();
      this.version      = viewEntity.getVersion();
      this.instanceName = viewInstanceDefinition.getName();
    }
  
    /**
     * Handles URL: /resources
     * Get all external resources for a view.
     *
     * @param headers  http headers
     * @param ui       uri info
     *
     * @return instance collection resource representation
     */
    @GET @ApiIgnore // until documented
    @Produces("text/plain")
    public Response getResources(String body, @Context HttpHeaders headers, @Context UriInfo ui) {
      return handleRequest(headers, body, ui, Request.Type.GET,
          createResource(viewName, instanceName));
    }
  
    /**
     * Handles: GET /resources/{resourceName} Get a specific external resource.
     *
     * @param resourceName  resource name
     *
     * @return resource service instance representation
     *
     * @throws IllegalArgumentException if the given resource name is unknown
     */
    @Path("{resourceName}")
    public Object getResource(@PathParam("resourceName") String resourceName) throws IOException {
  
      Object service = resourceServiceMap.get(resourceName);
      if (service == null) {
        throw new IllegalArgumentException("A resource type " + resourceName + " for view instance " +
            viewName + "/" + instanceName + " can not be found.");
      }
  
      return service;
    }
  
    // ----- helper methods ----------------------------------------------------
  
    /**
     * Register a sub-resource service.
     *
     * @param resourceName  the resource name
     * @param service       the service
     */
    public void addResourceService(String resourceName, Object service) {
      resourceServiceMap.put(resourceName, service);
    }
  
    /**
     * Create an view instance resource.
     *
     * @param viewName      view name
     * @param instanceName  instance name
     *
     * @return a view instance resource
     */
    private ResourceInstance createResource(String viewName, String instanceName) {
      Map<Resource.Type,String> mapIds = new HashMap<>();
      mapIds.put(Resource.Type.View, viewName);
      mapIds.put(Resource.Type.ViewVersion, version);
      mapIds.put(Resource.Type.ViewInstance, instanceName);
      return createResource(type, mapIds);
    }
  }
  