/**
* Copyright 2013 Google Inc. All Rights Reserved.
*
* 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.apphosting.utils.servlet;
import com.google.appengine.api.LifecycleManager;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
/**
* Runs the user-registered shutdown hook, if any.
*
* This filter should be mapped to /_ah/stop on VM Runtimes so stop requests
* are properly handled.
*
*/
public class VmStopFilter implements Filter {
private static final Logger logger = Logger.getLogger(VmStopFilter.class.getName());
private static final long SHUTDOWN_HOOK_DEADLINE_MILLIS =
TimeUnit.SECONDS.convert(60, TimeUnit.MILLISECONDS);
@Override
public void init(FilterConfig config) {
}
@Override
public void destroy() {
}
/**
* Handle stop requests.
*
* Stop requests are intercepted by this filter and never forwarded to user code.
*/
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
// Requests to /_ah/stop are filtered by the appserver (and soon VM-local nginx). Any stop
// requests that make it here are from trusted code.
logger.info("Running shutdown hook");
long deadline = System.currentTimeMillis() + SHUTDOWN_HOOK_DEADLINE_MILLIS;
LifecycleManager.getInstance().beginShutdown(deadline);
response.setContentType("text/plain");
response.getWriter().write("ok");
}
}