Java tutorial
package org.sigmah.server.servlet; /* * #%L * Sigmah * %% * Copyright (C) 2010 - 2016 URD * %% * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program. If not, see * <http://www.gnu.org/licenses/gpl-3.0.html>. * #L% */ import java.io.IOException; import java.io.InputStream; import java.nio.file.NoSuchFileException; import java.nio.file.StandardCopyOption; import java.util.ArrayList; import java.util.Date; import java.util.Map; import java.util.UUID; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.collections4.MapUtils; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.io.FilenameUtils; import org.apache.commons.lang3.StringUtils; import org.sigmah.client.page.RequestParameter; import org.sigmah.client.util.ClientUtils; import org.sigmah.server.dao.FileDAO; import org.sigmah.server.dao.MonitoredPointDAO; import org.sigmah.server.dao.OrganizationDAO; import org.sigmah.server.dao.ProjectDAO; import org.sigmah.server.domain.Organization; import org.sigmah.server.domain.Project; import org.sigmah.server.domain.reminder.MonitoredPoint; import org.sigmah.server.domain.reminder.MonitoredPointList; import org.sigmah.server.domain.value.FileVersion; import org.sigmah.server.file.BackupArchiveManager; import org.sigmah.server.file.FileStorageProvider; import org.sigmah.server.file.LogoManager; import org.sigmah.server.file.util.MultipartRequest; import org.sigmah.server.file.util.MultipartRequestCallback; import org.sigmah.server.servlet.base.AbstractServlet; import org.sigmah.server.servlet.base.ServletExecutionContext; import org.sigmah.server.servlet.base.StatusServletException; import org.sigmah.server.servlet.util.ResponseHelper; import org.sigmah.shared.dto.reminder.MonitoredPointDTO; import org.sigmah.shared.dto.value.FileUploadUtils; import org.sigmah.shared.dto.value.FileVersionDTO; import org.sigmah.shared.servlet.FileUploadResponse; import org.sigmah.shared.servlet.ServletConstants.ServletMethod; import org.sigmah.shared.util.FileType; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.gwt.http.client.Response; import com.google.inject.Inject; import com.google.inject.Singleton; import org.sigmah.server.handler.util.Conflicts; import org.sigmah.shared.Language; /** * File upload and download servlet. * * @author Denis Colliot (dcolliot@ideia.fr) */ @Singleton public class FileServlet extends AbstractServlet { /** * Serial version UID. */ private static final long serialVersionUID = -8126580127468427311L; /** * Logger. */ private static final Logger LOG = LoggerFactory.getLogger(FileServlet.class); /** * Injected application {@link FileStorageProvider}. */ @Inject private FileStorageProvider fileStorageProvider; /** * Injected application {@link LogoManager}. */ @Inject private LogoManager logoManager; /** * Injected {@link OrganizationDAO}. */ @Inject private OrganizationDAO organizationDAO; /** * Injected {@link FileDAO}. */ @Inject private FileDAO fileDAO; /** * Injected {@link BackupArchiveManager}. */ @Inject private BackupArchiveManager backupArchiveManager; /** * Injected {@link ProjectDAO}. */ @Inject private ProjectDAO projectDAO; /** * Injected {@link MonitoredPointDAO}. */ @Inject private MonitoredPointDAO monitoredPointDAO; /** * Injected {@link Conflicts}. */ @Inject private Conflicts conflicts; // --------------------------------------------------------------------------------------- // // DOWNLOAD METHODS. // // --------------------------------------------------------------------------------------- /** * See {@link ServletMethod#DOWNLOAD_LOGO} for JavaDoc. * * @param request * The HTTP request containing the file id parameter. * @param response * The HTTP response on which the file content is written. * @param context * The execution context. * @throws Exception * If an error occurs during process. */ protected void downloadLogo(final HttpServletRequest request, final HttpServletResponse response, final ServletExecutionContext context) throws Exception { // Retrieves the file id. final String id = getParameter(request, RequestParameter.ID, false); if (LOG.isDebugEnabled()) { LOG.debug("Downloads logo with id '{}'.", id); } try { downloadBase64(id, fileStorageProvider.open(id), response); } catch (final NoSuchFileException e) { if (LOG.isInfoEnabled()) { LOG.info("No logo found for id '" + id + "'.", e); } throw new StatusServletException(Response.SC_NOT_FOUND, e); } } /** * See {@link ServletMethod#DOWNLOAD_FILE} for JavaDoc. * * @param request * The HTTP request containing the file id parameter. * @param response * The HTTP response on which the file content is written. * @param context * The execution context. * @throws Exception * If an error occurs during process. */ protected void downloadFile(final HttpServletRequest request, final HttpServletResponse response, final ServletExecutionContext context) throws Exception { // Retrieves the file version id. final Integer fileVersionId = getIntegerParameter(request, RequestParameter.ID, false); LOG.debug("Downloads file with version id '{}'.", fileVersionId); try { final FileVersion version = fileDAO.getVersion(fileVersionId); final String name = version.getName() + '.' + version.getExtension(); final String path = version.getPath(); download(path, name, fileStorageProvider.open(path), response); } catch (final NoSuchFileException e) { LOG.info("No file found for version id '" + fileVersionId + "'.", e); throw new StatusServletException(Response.SC_NOT_FOUND, e); } } /** * See {@link ServletMethod#DOWNLOAD_ARCHIVE} for JavaDoc. * * @param request * The HTTP request containing the file id parameter. * @param response * The HTTP response on which the file content is written. * @param context * The execution context. * @throws Exception * If an error occurs during process. */ protected void downloadArchive(final HttpServletRequest request, final HttpServletResponse response, final ServletExecutionContext context) throws Exception { // Retrieves the file id. final String id = getParameter(request, RequestParameter.ID, false); if (LOG.isDebugEnabled()) { LOG.debug("Downloads archive with id '{}'.", id); } try { download(id, backupArchiveManager.open(id), response); } catch (final NoSuchFileException e) { if (LOG.isInfoEnabled()) { LOG.info("No archive found for id '" + id + "'.", e); } throw new StatusServletException(Response.SC_NOT_FOUND, e); } } /** * Downloads the given {@code id} file on given {@code response} stream. * * @param id * The file id. * @param in * The file input stream. * @param response * The HTTP response on which the file content is written. * @throws Exception * If an error occurs during process. */ private static void download(final String id, final InputStream in, final HttpServletResponse response) throws Exception { download(id, "file_" + id, in, response); } /** * Downloads the given {@code id} file on given {@code response} stream. * * @param id * The file id. * @param fileName * Name sent in the response header. * @param in * The file input stream. * @param response * The HTTP response on which the file content is written. * @throws Exception * If an error occurs during process. */ private static void download(final String id, String fileName, final InputStream in, final HttpServletResponse response) throws Exception { final FileType fileType = fileTypeFromFileId(id); ResponseHelper.executeDownload(response, in, fileType != null ? fileType.getContentType() : null, fileName, null); } private static void downloadBase64(final String id, final InputStream in, final HttpServletResponse response) throws IOException { final FileType fileType = fileTypeFromFileId(id); ResponseHelper.executeDownload(response, in, fileType != null ? fileType.getContentType() : null, null, null, ResponseHelper.ContentDisposition.BASE64); } private static FileType fileTypeFromFileId(String fileName) { final String extension = FilenameUtils.getExtension(fileName); return FileType.fromExtension(extension); } // --------------------------------------------------------------------------------------- // // UPLOAD METHODS. // // --------------------------------------------------------------------------------------- /** * See {@link ServletMethod#UPLOAD_ORGANIZATION_LOGO} for JavaDoc. * * @param request * The HTTP request containing the Organization id parameter. * @param response * The HTTP response on which the file content is written. * @param context * The execution context. * @throws java.io.IOException * If an error occured while reading or writing to the socket or if an error occured while storing the * uploaded file. * @throws org.sigmah.server.servlet.base.StatusServletException * If the id parameter was not found or not parseable or if the request type is not MULTIPART or if the file * exceeded the maximum allowed size. * @throws org.apache.commons.fileupload.FileUploadException * If an error occured while reading the uploaded file. * @throws javax.servlet.ServletException * If the given organization could not be found. */ protected void uploadOrganizationLogo(final HttpServletRequest request, final HttpServletResponse response, final ServletExecutionContext context) throws IOException, StatusServletException, ServletException, FileUploadException { // -- // Retrieving parameters from request. // -- final Integer organizationId = getIntegerParameter(request, RequestParameter.ID, false); // -- // Retrieving Organization entity. // -- final Organization organization = organizationDAO.findById(organizationId); if (organization == null) { throw new ServletException("Cannot find Organization with id '" + organizationId + "'."); } final String previousLogoFileName = organization.getLogo(); // -- // Verifying content length. // -- final int contentLength = request.getContentLength(); if (contentLength == 0) { LOG.error("Empty logo file."); throw new StatusServletException(Response.SC_NO_CONTENT); } if (contentLength > FileUploadUtils.MAX_UPLOAD_IMAGE_SIZE) { LOG.error("Logo file's size is too big to be uploaded (size: {}, maximum : {}).", contentLength, FileUploadUtils.MAX_UPLOAD_IMAGE_SIZE); throw new StatusServletException(Response.SC_REQUEST_ENTITY_TOO_LARGE); } // -- // Saving new logo. // -- organization.setLogo(organization.getId() + "_" + new Date().getTime()); processUpload(new MultipartRequest(request), response, organization.getLogo(), true); organizationDAO.persist(organization, context.getUser()); // -- // Deleting previous logo file. // -- if (StringUtils.isNotBlank(previousLogoFileName)) { fileStorageProvider.delete(previousLogoFileName); } response.getWriter().write(organization.getLogo()); } /** * See {@link ServletMethod#UPLOAD} for JavaDoc. * * @param request * The HTTP request containing the file id parameter. * @param response * The HTTP response on which the file content is written. * @param context * The execution context. * @throws Exception * If an error occurs during process. */ protected void upload(final HttpServletRequest request, final HttpServletResponse response, final ServletExecutionContext context) throws Exception { // -- // Verify content length. // -- final int contentLength = request.getContentLength(); if (contentLength == 0) { LOG.error("Empty file."); throw new StatusServletException(Response.SC_NO_CONTENT); } if (contentLength > FileUploadUtils.MAX_UPLOAD_FILE_SIZE) { LOG.error("File's size is too big to be uploaded (size: {}, maximum : {}).", contentLength, FileUploadUtils.MAX_UPLOAD_FILE_SIZE); throw new StatusServletException(Response.SC_REQUEST_ENTITY_TOO_LARGE); } final String fileName = generateUniqueName(); // -- // Writing the file. // -- final MultipartRequest multipartRequest = new MultipartRequest(request); final long size = this.processUpload(multipartRequest, response, fileName, false); final Map<String, String> properties = multipartRequest.getProperties(); conflicts.searchForFileAddConflicts(properties, context.getLanguage(), context.getUser()); // -- // Create the associated entries in File and FileVersion tables. // -- final Integer fileId = fileDAO.saveOrUpdate(properties, fileName, (int) size); final FileVersion fileVersion = fileDAO.getLastVersion(fileId); // -- // If a monitored point must be created. // -- final MonitoredPoint monitoredPoint = parseMonitoredPoint(properties); if (monitoredPoint != null) { final Integer projectId = ClientUtils.asInt(properties.get(FileUploadUtils.DOCUMENT_PROJECT)); final Project project = projectDAO.findById(projectId); monitoredPoint.setFile(fileDAO.findById(fileId)); MonitoredPointList list = project.getPointsList(); if (list == null) { list = new MonitoredPointList(); project.setPointsList(list); } if (list.getPoints() == null) { list.setPoints(new ArrayList<MonitoredPoint>()); } // Adds the point to the list. list.addMonitoredPoint(monitoredPoint); // Saves monitored point. monitoredPointDAO.persist(monitoredPoint, context.getUser()); } final MonitoredPointDTO monitoredPointDTO = mapper().map(monitoredPoint, new MonitoredPointDTO(), MonitoredPointDTO.Mode.BASE); final FileVersionDTO fileVersionDTO = mapper().map(fileVersion, new FileVersionDTO()); response.setContentType(FileType.HTML.getContentType()); response.getWriter().write(FileUploadResponse.serialize(fileVersionDTO, monitoredPointDTO)); } // --------------------------------------------------------------------------------------- // // UTILITY METHODS. // // --------------------------------------------------------------------------------------- /** * Processes the file upload. * * @param request * The HTTP request. * @param response * The HTTP response. * @param context * The execution context. * @param filename * The uploaded physical file name. * @param logo * {@code true} if the upload concerns an organization logo, {@code false} otherwise. * @throws java.io.IOException * If an error occured while reading or writing to the socket or if an error occured while storing the * uploaded file. * @throws org.sigmah.server.servlet.base.StatusServletException * if the request type is not MULTIPART or if the file exceeded the maximum allowed size. * @throws org.apache.commons.fileupload.FileUploadException * If an error occured while reading the uploaded file. */ private long processUpload(final MultipartRequest multipartRequest, final HttpServletResponse response, final String filename, final boolean logo) throws StatusServletException, IOException, FileUploadException { LOG.debug("Starting file uploading..."); final long[] size = { 0L }; multipartRequest.parse(new MultipartRequestCallback() { @Override public void onInputStream(InputStream inputStream, String itemName, String mimeType) throws IOException { // Retrieving file name. // If a name (id) is provided, we use it. If not, using the name of the uploaded file. final String name = StringUtils.isNotBlank(filename) ? filename : itemName; try (final InputStream stream = inputStream) { LOG.debug("Reads image content from the field ; name: '{}'.", name); if (logo) { size[0] = logoManager.updateLogo(stream, name); } else { size[0] = fileStorageProvider.copy(stream, name, StandardCopyOption.REPLACE_EXISTING); } response.setStatus(Response.SC_ACCEPTED); // FIXME : perhaps keep the response above for error catching // response.getWriter().write("ok"); LOG.debug("File '{}' upload has been successfully processed.", name); } } }); return size[0]; } /** * Generates a {@link MonitoredPoint} instance from the given {@code properties}.<br> * Following attributes of the generated monitored point are set: * <ul> * <li>{@code label}</li> * <li>{@code expectedDate}</li> * <li>{@code deleted} (set to {@code false})</li> * </ul> * * @param properties * The properties. * @return The monitored point instance. * @throws UnsupportedOperationException * If the {@code properties} cannot be used to generate a <em>valid</em> {@link MonitoredPoint} instance. */ private static MonitoredPoint parseMonitoredPoint(final Map<String, String> properties) { if (MapUtils.isEmpty(properties)) { return null; } final String label = properties.get(FileUploadUtils.MONITORED_POINT_LABEL); final String expectedDateTime = properties.get(FileUploadUtils.MONITORED_POINT_DATE); if (StringUtils.isBlank(label) || StringUtils.isBlank(expectedDateTime)) { return null; } try { final MonitoredPoint monitoredPoint = new MonitoredPoint(); monitoredPoint.setLabel(label); monitoredPoint.setExpectedDate(new Date(Long.valueOf(expectedDateTime))); monitoredPoint.setDeleted(false); return monitoredPoint; } catch (final Exception e) { throw new UnsupportedOperationException( "Error occures while generating monitored point from properties.", e); } } /** * Computes and returns a unique string identifier to name files. * * @return A unique string identifier. */ public static String generateUniqueName() { // Adds the timestamp to ensure the id uniqueness. return UUID.randomUUID().toString() + new Date().getTime(); } }