// Copyright (C) 2006 Google Inc.
//
// Licensed 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.google.enterprise.connector.servlet;

import com.google.enterprise.connector.instantiator.InstantiatorException;
import com.google.enterprise.connector.manager.Manager;
import com.google.enterprise.connector.persist.ConnectorNotFoundException;

import java.io.PrintWriter;
import java.util.logging.Logger;

/**
 * Admin servlet to restart repository traversal for a given connector.
 * This will start crawing the repository from the begining, reindexing
 * the contents.
 *
 * Usage:
 * -----
 * To restart the indexing traversal for a Connector:
 *   http://[cm_host_addr]/connector-manager/restartConnectorTraversal?ConnectorName=[connector_name]
 * where [connector_name] is the name of a connector instance.
 */
public class RestartConnectorTraversal extends ConnectorManagerGetServlet {
  private static final Logger LOGGER =
      Logger.getLogger(RestartConnectorTraversal.class.getName());

  @Override
  protected void processDoGet(String connectorName, String lang,
      Manager manager, PrintWriter out) {
    handleDoGet(connectorName, manager, out);
  }

  /**
   * Handler for doGet in order to do unit tests. Returns the connector
   * status.
   *
   * @param connectorName
   * @param manager
   * @param out PrintWriter where the response is written
   */
  public static void handleDoGet(String connectorName, Manager manager,
      PrintWriter out) {
    try {
      // Force the connector to reindex the repository.
      manager.restartConnectorTraversal(connectorName);
    } catch (ConnectorNotFoundException cnfe) {
      ServletUtil.writeResponse(out, new ConnectorMessageCode(
          ConnectorMessageCode.EXCEPTION_CONNECTOR_NOT_FOUND, connectorName));
      LOGGER.warning("Connector not found " + connectorName);
      return;
    } catch (InstantiatorException ie) {
      ServletUtil.writeResponse(out, new ConnectorMessageCode(
          ConnectorMessageCode.EXCEPTION_INSTANTIATOR, connectorName));
      LOGGER.warning(ie.getMessage());
      return;
    }

    // Write out the successful status.
    ServletUtil.writeResponse(out, new ConnectorMessageCode(
        ConnectorMessageCode.SUCCESS_RESTART_TRAVERSAL, connectorName));
  }
}