Java tutorial
/* * (C) Copyright 2006-2015 Nuxeo SA (http://nuxeo.com/) and others. * * 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. * * Contributors: * Thierry Delprat * Florent Guillaume */ package org.nuxeo.ecm.platform.ui.web.download; import static org.nuxeo.ecm.core.io.download.DownloadService.NXBIGBLOB; import static org.nuxeo.ecm.core.io.download.DownloadService.NXBIGZIPFILE; import static org.nuxeo.ecm.core.io.download.DownloadService.NXDOWNLOADINFO; import static org.nuxeo.ecm.core.io.download.DownloadService.NXFILE; import java.io.File; import java.io.IOException; import java.net.URI; import java.net.URISyntaxException; import java.net.URLEncoder; import java.util.Arrays; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.commons.lang.StringUtils; import org.apache.commons.lang3.tuple.Pair; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.nuxeo.common.Environment; import org.nuxeo.ecm.core.api.Blob; import org.nuxeo.ecm.core.api.Blobs; import org.nuxeo.ecm.core.api.CoreInstance; import org.nuxeo.ecm.core.api.CoreSession; import org.nuxeo.ecm.core.api.DocumentModel; import org.nuxeo.ecm.core.api.DocumentRef; import org.nuxeo.ecm.core.api.IdRef; import org.nuxeo.ecm.core.api.NuxeoException; import org.nuxeo.ecm.core.io.download.DownloadHelper; import org.nuxeo.ecm.core.io.download.DownloadService; import org.nuxeo.ecm.platform.web.common.vh.VirtualHostHelper; import org.nuxeo.runtime.api.Framework; import org.nuxeo.runtime.transaction.TransactionHelper; /** * Simple download servlet used for big files that can not be downloaded from within the JSF context (because of * buffered ResponseWrapper). */ public class DownloadServlet extends HttpServlet { private static final long serialVersionUID = 1L; private static final Log log = LogFactory.getLog(DownloadServlet.class); /** @deprecated since 7.4, use nxfile instead */ @Deprecated public static final String NXBIGFILE = "nxbigfile"; @Override public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException { try { handleDownload(req, resp); } catch (IOException ioe) { DownloadHelper.handleClientDisconnect(ioe); } } protected void handleDownload(HttpServletRequest req, HttpServletResponse resp) throws IOException { String requestURI; try { requestURI = new URI(req.getRequestURI()).getPath(); } catch (URISyntaxException e) { requestURI = req.getRequestURI(); } // remove context String context = VirtualHostHelper.getContextPath(req) + "/"; if (!requestURI.startsWith(context)) { resp.sendError(HttpServletResponse.SC_NOT_FOUND, "Invalid URL syntax"); return; } String localURI = requestURI.substring(context.length()); // find what to do int slash = localURI.indexOf('/'); if (slash < 0) { resp.sendError(HttpServletResponse.SC_NOT_FOUND, "Invalid URL syntax"); return; } String what = localURI.substring(0, slash); String path = localURI.substring(slash + 1); switch (what) { case NXFILE: case NXBIGFILE: downloadBlob(req, resp, path, false); break; case NXDOWNLOADINFO: // used by nxdropout.js downloadBlob(req, resp, path, true); break; case NXBIGZIPFILE: // handle the download for a big zip created in the tmp directory; // the name of this zip is sent in the request handleDownloadTemporaryZip(req, resp, path); break; case NXBIGBLOB: // handle the download of a Blob referenced in HTTP Request or Session handleDownloadSessionBlob(req, resp, path); break; default: resp.sendError(HttpServletResponse.SC_NOT_FOUND, "Invalid URL syntax"); } } protected void downloadBlob(HttpServletRequest req, HttpServletResponse resp, String urlPath, boolean info) throws IOException { String[] parts = urlPath.split("/"); if (parts.length < 2) { resp.sendError(HttpServletResponse.SC_NOT_FOUND, "Invalid URL syntax"); return; } String repositoryName = parts[0]; String docId = parts[1]; boolean tx = false; try { if (!TransactionHelper.isTransactionActive()) { // Manually start and stop a transaction around repository access to be able to release transactional // resources without waiting for the download that can take a long time (longer than the transaction // timeout) especially if the client or the connection is slow. tx = TransactionHelper.startTransaction(); } try (CoreSession session = CoreInstance.openCoreSession(repositoryName)) { DocumentRef docRef = new IdRef(docId); if (!session.exists(docRef)) { resp.sendError(HttpServletResponse.SC_NOT_FOUND, "No Blob found"); return; } DocumentModel doc = session.getDocument(docRef); Pair<String, String> pair = parsePath(urlPath); String xpath = pair.getLeft(); String filename = pair.getRight(); DownloadService downloadService = Framework.getService(DownloadService.class); if (info) { Blob blob = downloadService.resolveBlob(doc, xpath); if (blob == null) { resp.sendError(HttpServletResponse.SC_NOT_FOUND, "No blob found"); return; } String downloadUrl = VirtualHostHelper.getBaseURL(req) + downloadService.getDownloadUrl(doc, xpath, filename); String result = blob.getMimeType() + ':' + URLEncoder.encode(blob.getFilename(), "UTF-8") + ':' + downloadUrl; resp.setContentType("text/plain"); resp.getWriter().write(result); resp.getWriter().flush(); } else { downloadService.downloadBlob(req, resp, doc, xpath, null, filename, "download"); } } } catch (NuxeoException e) { if (tx) { TransactionHelper.setTransactionRollbackOnly(); } throw new IOException(e); } finally { if (tx) { TransactionHelper.commitOrRollbackTransaction(); } } } // first two parts are repository name and doc id, already parsed protected static Pair<String, String> parsePath(String urlPath) { String[] parts = urlPath.split("/"); int length = parts.length; String xpath; String filename; if (length == 2) { xpath = DownloadService.BLOBHOLDER_0; filename = null; } else if (length == 3) { xpath = parts[2]; filename = null; } else { xpath = StringUtils.join(Arrays.asList(parts).subList(2, length - 1), "/"); filename = parts[length - 1]; } return Pair.of(xpath, filename); } // used by DownloadFile operation protected void handleDownloadSessionBlob(HttpServletRequest req, HttpServletResponse resp, String blobId) throws IOException { Blob blob = (Blob) req.getAttribute(blobId); if (blob != null) { req.removeAttribute(blobId); } else { HttpSession session = req.getSession(false); if (session == null) { log.error("Unable to download blob " + blobId + " since the holding http session does not exist"); return; } blob = (Blob) session.getAttribute(blobId); if (blob == null) { return; } session.removeAttribute(blobId); } DownloadService downloadService = Framework.getService(DownloadService.class); downloadService.downloadBlob(req, resp, null, null, blob, null, "operation"); } // used by ClipboardActionsBean protected void handleDownloadTemporaryZip(HttpServletRequest req, HttpServletResponse resp, String filePath) throws IOException { String[] pathParts = filePath.split("/"); String tmpFileName = pathParts[0]; File tmpZip = new File(Environment.getDefault().getTemp(), tmpFileName); try { Blob zipBlob = Blobs.createBlob(tmpZip); DownloadService downloadService = Framework.getService(DownloadService.class); downloadService.downloadBlob(req, resp, null, null, zipBlob, "clipboard.zip", "clipboardZip"); } finally { tmpZip.delete(); } } }