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.waveprotocol.box.server.rpc; import com.google.inject.Inject; import com.google.inject.Singleton; import com.typesafe.config.Config; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileItemFactory; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.apache.commons.io.FilenameUtils; import org.waveprotocol.box.attachment.AttachmentMetadata; import org.waveprotocol.box.server.attachment.AttachmentService; import org.waveprotocol.box.server.authentication.SessionManager; import org.waveprotocol.box.server.persistence.AttachmentStore.AttachmentData; import org.waveprotocol.box.server.persistence.AttachmentUtil; import org.waveprotocol.box.server.waveserver.WaveServerException; import org.waveprotocol.box.server.waveserver.WaveletProvider; import org.waveprotocol.wave.media.model.AttachmentId; import org.waveprotocol.wave.model.id.InvalidIdException; import org.waveprotocol.wave.model.id.WaveletName; import org.waveprotocol.wave.model.wave.ParticipantId; import org.waveprotocol.wave.util.logging.Log; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.*; import java.net.URLDecoder; import java.util.Calendar; import java.util.List; import java.util.logging.Level; /** * Serves attachments from a provided store. * * @author akaplanov@gmail.com (A. Kaplanov) * */ @SuppressWarnings("serial") @Singleton public class AttachmentServlet extends HttpServlet { public static String ATTACHMENT_URL = "/attachment"; public static String THUMBNAIL_URL = "/thumbnail"; public static String THUMBNAIL_PATTERN_FORMAT_NAME = "png"; public static String THUMBNAIL_PATTERN_DEFAULT = "default"; private static final Log LOG = Log.get(AttachmentServlet.class); private final AttachmentService service; private final WaveletProvider waveletProvider; private final SessionManager sessionManager; private final String thumbnailPattternsDirectory; @Inject private AttachmentServlet(AttachmentService service, WaveletProvider waveletProvider, SessionManager sessionManager, Config config) { this.service = service; this.waveletProvider = waveletProvider; this.sessionManager = sessionManager; this.thumbnailPattternsDirectory = config.getString("core.thumbnail_patterns_directory"); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { AttachmentId attachmentId = getAttachmentIdFromRequest(request); if (attachmentId == null) { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } String fileName = getFileNameFromRequest(request); String waveRefStr = getWaveRefFromRequest(request); AttachmentMetadata metadata = service.getMetadata(attachmentId); WaveletName waveletName; if (metadata == null) { // Old attachments does not have metainfo. if (waveRefStr != null) { waveletName = AttachmentUtil.waveRef2WaveletName(waveRefStr); } else { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } } else { waveletName = AttachmentUtil.waveRef2WaveletName(metadata.getWaveRef()); } ParticipantId user = sessionManager.getLoggedInUser(request.getSession(false)); boolean isAuthorized = false; try { isAuthorized = waveletProvider.checkAccessPermission(waveletName, user); } catch (WaveServerException e) { LOG.warning("Problem while authorizing user: " + user + " for wavelet: " + waveletName, e); } if (!isAuthorized) { response.sendError(HttpServletResponse.SC_FORBIDDEN); return; } if (metadata == null) { metadata = service.buildAndStoreMetadataWithThumbnail(attachmentId, waveletName, fileName, null); } String contentType; AttachmentData data; if (request.getRequestURI().startsWith(ATTACHMENT_URL)) { contentType = metadata.getMimeType(); data = service.getAttachment(attachmentId); if (data == null) { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } } else if (request.getRequestURI().startsWith(THUMBNAIL_URL)) { if (metadata.hasImageMetadata()) { contentType = AttachmentService.THUMBNAIL_MIME_TYPE; data = service.getThumbnail(attachmentId); if (data == null) { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } } else { contentType = THUMBNAIL_PATTERN_FORMAT_NAME; data = getThumbnailByContentType(metadata.getMimeType()); } } else { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } if (data == null) { response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } response.setContentType(contentType); response.setContentLength((int) data.getSize()); response.setHeader("Content-Disposition", "attachment; filename=\"" + metadata.getFileName() + "\""); response.setStatus(HttpServletResponse.SC_OK); response.setDateHeader("Last-Modified", Calendar.getInstance().getTimeInMillis()); AttachmentUtil.writeTo(data.getInputStream(), response.getOutputStream()); LOG.info("Fetched attachment with id '" + attachmentId + "'"); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // Process only multipart requests. if (ServletFileUpload.isMultipartContent(request)) { // Create a factory for disk-based file items. FileItemFactory factory = new DiskFileItemFactory(); // Create a new file upload handler. ServletFileUpload upload = new ServletFileUpload(factory); // Parse the request. try { @SuppressWarnings("unchecked") List<FileItem> items = upload.parseRequest(request); AttachmentId id = null; String waveRefStr = null; FileItem fileItem = null; for (FileItem item : items) { // Process only file upload - discard other form item types. if (item.isFormField()) { if (item.getFieldName().equals("attachmentId")) { id = AttachmentId.deserialise(item.getString()); } if (item.getFieldName().equals("waveRef")) { waveRefStr = item.getString(); } } else { fileItem = item; } } if (id == null) { response.sendError(HttpServletResponse.SC_BAD_REQUEST, "No attachment Id in the request."); return; } if (waveRefStr == null) { response.sendError(HttpServletResponse.SC_BAD_REQUEST, "No wave reference in request."); return; } WaveletName waveletName = AttachmentUtil.waveRef2WaveletName(waveRefStr); ParticipantId user = sessionManager.getLoggedInUser(request.getSession(false)); boolean isAuthorized = waveletProvider.checkAccessPermission(waveletName, user); if (!isAuthorized) { response.sendError(HttpServletResponse.SC_FORBIDDEN); return; } // Get only the file name not whole path. if (fileItem != null && fileItem.getName() != null) { String fileName = FilenameUtils.getName(fileItem.getName()); service.storeAttachment(id, fileItem.getInputStream(), waveletName, fileName, user); response.setStatus(HttpServletResponse.SC_CREATED); String msg = String.format("The file with name: %s and id: %s was created successfully.", fileName, id); LOG.fine(msg); response.getWriter().print("OK"); response.flushBuffer(); } } catch (Exception e) { LOG.severe("Upload error", e); response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "An error occurred while upload the file : " + e.getMessage()); } } else { LOG.severe("Request contents type is not supported by the servlet."); response.sendError(HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE, "Request contents type is not supported by the servlet."); } } private static AttachmentId getAttachmentIdFromRequest(HttpServletRequest request) { if (request.getPathInfo().length() == 0) { return null; } String id = getAttachmentIdStringFromRequest(request); try { return AttachmentId.deserialise(id); } catch (InvalidIdException ex) { LOG.log(Level.SEVERE, "Deserialize attachment Id " + id, ex); return null; } } private static String getAttachmentIdStringFromRequest(HttpServletRequest request) { // Discard the leading '/' in the pathinfo. return request.getPathInfo().substring(1); } private AttachmentData getThumbnailByContentType(String contentType) throws IOException { File file = new File(thumbnailPattternsDirectory, contentType.replaceAll("/", "_")); if (!file.exists()) { file = new File(thumbnailPattternsDirectory, THUMBNAIL_PATTERN_DEFAULT); } final File thumbFile = file; return new AttachmentData() { @Override public InputStream getInputStream() throws IOException { return new FileInputStream(thumbFile); } @Override public long getSize() { return thumbFile.length(); } }; } private static String getFileNameFromRequest(HttpServletRequest request) { String fileName = request.getParameter("fileName"); return fileName != null ? fileName : ""; } private static String getWaveRefFromRequest(HttpServletRequest request) { String waveRefStrEncoded = request.getParameter("waveRef"); String waveRefStr = null; if (waveRefStrEncoded != null) { try { waveRefStr = URLDecoder.decode(waveRefStrEncoded, "UTF-8"); } catch (UnsupportedEncodingException e) { LOG.warning("Problem decoding: " + waveRefStrEncoded, e); } } return waveRefStr; } }