Java tutorial
/* * 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.sling.distribution.servlet; import javax.servlet.ServletException; import java.io.IOException; import java.io.InputStream; import java.util.concurrent.atomic.AtomicInteger; import org.apache.commons.io.IOUtils; import org.apache.felix.scr.annotations.sling.SlingServlet; import org.apache.http.entity.ContentType; import org.apache.sling.api.SlingHttpServletRequest; import org.apache.sling.api.SlingHttpServletResponse; import org.apache.sling.api.resource.ResourceResolver; import org.apache.sling.api.servlets.SlingAllMethodsServlet; import org.apache.sling.distribution.DistributionRequest; import org.apache.sling.distribution.common.DistributionException; import org.apache.sling.distribution.packaging.DistributionPackageProcessor; import org.apache.sling.distribution.packaging.impl.DistributionPackageUtils; import org.apache.sling.distribution.packaging.DistributionPackage; import org.apache.sling.distribution.packaging.DistributionPackageExporter; import org.apache.sling.distribution.resources.DistributionResourceTypes; import org.apache.sling.distribution.util.RequestUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Servlet to handle fetching of distribution content. */ @SuppressWarnings("serial") @SlingServlet(resourceTypes = DistributionResourceTypes.EXPORTER_RESOURCE_TYPE, methods = "POST") public class DistributionPackageExporterServlet extends SlingAllMethodsServlet { private final Logger log = LoggerFactory.getLogger(getClass()); @Override protected void doPost(SlingHttpServletRequest request, SlingHttpServletResponse response) throws ServletException, IOException { String operation = request.getParameter("operation"); try { if ("delete".equals(operation)) { deletePackage(request, response); } else if ("fetch".equals(operation)) { exportOnePackage(request, response, false); } else { exportOnePackage(request, response, true); } } catch (Throwable t) { response.setStatus(503); log.error("error while exporting package", t); } } private void exportOnePackage(final SlingHttpServletRequest request, final SlingHttpServletResponse response, final boolean delete) throws ServletException, IOException { DistributionPackageExporter distributionPackageExporter = request.getResource() .adaptTo(DistributionPackageExporter.class); final long start = System.currentTimeMillis(); response.setContentType(ContentType.APPLICATION_OCTET_STREAM.toString()); DistributionRequest distributionRequest = RequestUtils.fromServletRequest(request); ResourceResolver resourceResolver = request.getResourceResolver(); final AtomicInteger fetched = new AtomicInteger(0); try { // get all items distributionPackageExporter.exportPackages(resourceResolver, distributionRequest, new DistributionPackageProcessor() { @Override public void process(DistributionPackage distributionPackage) { fetched.incrementAndGet(); InputStream inputStream = null; int bytesCopied = -1; try { inputStream = DistributionPackageUtils.createStreamWithHeader(distributionPackage); bytesCopied = IOUtils.copy(inputStream, response.getOutputStream()); } catch (IOException e) { log.error("cannot process package", e); } finally { IOUtils.closeQuietly(inputStream); } String packageId = distributionPackage.getId(); if (delete) { // delete the package permanently distributionPackage.delete(); } // everything ok response.setStatus(200); log.debug("exported package {} was sent (and deleted={}), bytes written {}", new Object[] { packageId, delete, bytesCopied }); } }); if (fetched.get() > 0) { long end = System.currentTimeMillis(); log.info("Processed distribution export request in {} ms: : fetched {}", new Object[] { end - start, fetched }); } else { response.setStatus(204); log.debug("nothing to fetch"); } } catch (Throwable e) { response.setStatus(503); log.error("error while exporting package", e); } } private void deletePackage(final SlingHttpServletRequest request, final SlingHttpServletResponse response) throws DistributionException { DistributionPackageExporter distributionPackageExporter = request.getResource() .adaptTo(DistributionPackageExporter.class); ResourceResolver resourceResolver = request.getResourceResolver(); String id = request.getParameter("id"); DistributionPackage distributionPackage = distributionPackageExporter.getPackage(resourceResolver, id); if (distributionPackage != null) { distributionPackage.delete(); log.debug("exported package {} was deleted", distributionPackage.getId()); response.setStatus(200); } else { response.setStatus(204); log.debug("nothing to delete {}", id); } } }