org.jodconverter.sample.webapp.ConverterServlet.java Source code

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Here is the source code for org.jodconverter.sample.webapp.ConverterServlet.java

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/*
 * Copyright 2004 - 2012 Mirko Nasato and contributors
 *           2016 - 2018 Simon Braconnier and contributors
 *
 * This file is part of JODConverter - Java OpenDocument Converter.
 *
 * 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 org.jodconverter.sample.webapp;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.jodconverter.DocumentConverter;

public class ConverterServlet extends HttpServlet {
    private static final long serialVersionUID = -591469426224201748L;

    private static final Logger LOGGER = LoggerFactory.getLogger(ConverterServlet.class);

    @Override
    public void init() throws ServletException {
        LOGGER.info("Servlet {} has started", this.getServletName());
    }

    @Override
    public void destroy() {
        LOGGER.info("Servlet {} has stopped", this.getServletName());
    }

    @Override
    protected void doPost(final HttpServletRequest request, final HttpServletResponse response)
            throws ServletException, IOException {

        if (!ServletFileUpload.isMultipartContent(request)) {
            response.sendError(HttpServletResponse.SC_FORBIDDEN, "Only multipart requests are allowed");
            return;
        }

        final WebappContext webappContext = WebappContext.get(getServletContext());

        final FileItem uploadedFile;
        try {
            uploadedFile = getUploadedFile(webappContext.getFileUpload(), request);
        } catch (FileUploadException fileUploadException) {
            throw new ServletException(fileUploadException);
        }
        if (uploadedFile == null) {
            throw new ServletException("Uploaded file is null");
        }
        final String inputExtension = FilenameUtils.getExtension(uploadedFile.getName());

        final String baseName = FilenameUtils.getBaseName(uploadedFile.getName());
        final File inputFile = File.createTempFile(baseName, "." + inputExtension);
        writeUploadedFile(uploadedFile, inputFile);

        final String outputExtension = FilenameUtils.getExtension(request.getRequestURI());
        final File outputFile = File.createTempFile(baseName, "." + outputExtension);
        try {
            final DocumentConverter converter = webappContext.getDocumentConverter();
            final long startTime = System.currentTimeMillis();
            converter.convert(inputFile).to(outputFile).execute();
            LOGGER.info(String.format("Successful conversion: %s [%db] to %s in %dms", inputExtension,
                    inputFile.length(), outputExtension, System.currentTimeMillis() - startTime));
            response.setContentType(
                    converter.getFormatRegistry().getFormatByExtension(outputExtension).getMediaType());
            response.setHeader("Content-Disposition", "attachment; filename=" + baseName + "." + outputExtension);
            sendFile(outputFile, response);
        } catch (Exception exception) {
            LOGGER.error(String.format("Failed conversion: %s [%db] to %s; %s; input file: %s", inputExtension,
                    inputFile.length(), outputExtension, exception, inputFile.getName()));
            throw new ServletException("Conversion failed", exception);
        } finally {
            FileUtils.deleteQuietly(outputFile);
            FileUtils.deleteQuietly(inputFile);
        }
    }

    private void sendFile(final File file, final HttpServletResponse response) throws IOException {

        response.setContentLength((int) file.length());
        try (InputStream inputStream = new FileInputStream(file)) {
            IOUtils.copy(inputStream, response.getOutputStream());
        }
    }

    private void writeUploadedFile(final FileItem uploadedFile, final File destinationFile)
            throws ServletException {

        try {
            uploadedFile.write(destinationFile);
        } catch (Exception exception) {
            throw new ServletException("Error writing uploaded file", exception);
        }
        uploadedFile.delete();
    }

    private FileItem getUploadedFile(final ServletFileUpload fileUpload, final HttpServletRequest request)
            throws FileUploadException {

        return fileUpload.parseRequest(request).stream().filter(fileItem -> !fileItem.isFormField()).findFirst()
                .orElse(null);
    }
}