ReportServlet.java

/*
** Module   : ReportServlet.java
** Abstract : ReportServlet provides report service for external clients.
**
** Copyright (c) 2017-2024, Golden Code Development Corporation.
**
** -#- -I- --Date-- ----------------Description----------------------
** 001 SBI 20170601 Created initial version.
** 002 GBB 20230512 Logging methods replaced by CentralLogger/ConversionStatus.
** 003 GBB 20240430 Replace jPod lib used for merging split docs with pdfbox.
*/
/*
** This program is free software: you can redistribute it and/or modify
** it under the terms of the GNU Affero 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 Affero General Public License for more details.
**
** You may find a copy of the GNU Affero GPL version 3 at the following
** location: https://www.gnu.org/licenses/agpl-3.0.en.html
** 
** Additional terms under GNU Affero GPL version 3 section 7:
** 
**   Under Section 7 of the GNU Affero GPL version 3, the following additional
**   terms apply to the works covered under the License.  These additional terms
**   are non-permissive additional terms allowed under Section 7 of the GNU
**   Affero GPL version 3 and may not be removed by you.
** 
**   0. Attribution Requirement.
** 
**     You must preserve all legal notices or author attributions in the covered
**     work or Appropriate Legal Notices displayed by works containing the covered
**     work.  You may not remove from the covered work any author or developer
**     credit already included within the covered work.
** 
**   1. No License To Use Trademarks.
** 
**     This license does not grant any license or rights to use the trademarks
**     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
**     of Golden Code Development Corporation. You are not authorized to use the
**     name Golden Code, FWD, or the names of any author or contributor, for
**     publicity purposes without written authorization.
** 
**   2. No Misrepresentation of Affiliation.
** 
**     You may not represent yourself as Golden Code Development Corporation or FWD.
** 
**     You may not represent yourself for publicity purposes as associated with
**     Golden Code Development Corporation, FWD, or any author or contributor to
**     the covered work, without written authorization.
** 
**   3. No Misrepresentation of Source or Origin.
** 
**     You may not represent the covered work as solely your work.  All modified
**     versions of the covered work must be marked in a reasonable way to make it
**     clear that the modified work is not originating from Golden Code Development
**     Corporation or FWD.  All modified versions must contain the notices of
**     attribution required in this license.
*/


package com.goldencode.p2j.admin.server;

import java.io.*;
import java.util.*;

import javax.servlet.*;
import javax.servlet.http.*;

import com.goldencode.p2j.admin.server.reports.ReportBuilder.*;
import com.goldencode.p2j.admin.server.reports.*;
import com.goldencode.p2j.admin.shared.*;

import com.goldencode.p2j.util.logging.*;

import org.apache.pdfbox.io.*;
import org.apache.pdfbox.multipdf.*;

/**
 * Report servlet handles print requests. Accepted report parameters are listed by
 * this enumeration ReportParameters.
 */
public class ReportServlet extends HttpServlet
{
   /** The buffer size to hold responses */
   private static final int BUFFER_SIZE = 102400;
   
   /** Logger. */
   private static final CentralLogger LOG = CentralLogger.get(ReportServlet.class);

   /** Max memory in bytes for the buffer writing to the temp merged pdf file. */
   private static final int MAX_BUFFER_MEMORY_BYTES = 1000 * 1000; // 1MB
   
   /**
    * Handles HTTP GET requests to build reports.
    * 
    * @param    req
    *           The http request
    * @param    resp
    *           The http response
    */
   @Override
   protected void doGet(HttpServletRequest req, HttpServletResponse resp)
   throws IOException
   {
      try
      {
         Enumeration<String> parameterNames = req.getParameterNames();

         ReportRequest reportRequest = new ReportRequest();

         LinkedHashMap<String, String> reportParameters = new LinkedHashMap<>();

         LinkedHashSet<String> selectedRowsList = new LinkedHashSet<String>();

         boolean printAction = false;

         while(parameterNames.hasMoreElements())
         {
            String name = parameterNames.nextElement();
            String value = req.getParameter(name);
            if (ReportParameters.REPORT_ID.getParameter().equals(name))
            {
               reportRequest.setReportId(value);
            }
            else if (ReportParameters.FILTER.getParameter().equals(name))
            {
               reportRequest.setFilter(value);
            }
            else if (ReportParameters.PAPER_FORMAT.getParameter().equals(name) ||
               ReportParameters.PAPER_ORIENT.getParameter().equals(name) ||
               ReportParameters.DETAILS.getParameter().equals(name) ||
               ReportParameters.REPORT_TYPE.getParameter().equals(name) ||
               ReportParameters.ACTION.getParameter().equals(name)
                  && (/*set print action */ printAction = true))
            {
               reportParameters.put(name, value);
            }
            else if (name.startsWith(ReportParameters.SELECTION.getParameter()))
            {
               if (!value.isEmpty())
               {
                  selectedRowsList.add(value);
               }
            }
            else if (name.startsWith(ReportParameters.EXTENSION.getParameter()))
            {
               reportParameters.put(name, value);
            }
         };

         reportRequest.setReportParameters(reportParameters);

         reportRequest.setSelectedRows(selectedRowsList.toArray(new String[0]));

         try (Document doc = ReportsManager.buildReport(reportRequest))
         {
            int parts = doc.getSplittedContent().size();

            if (parts > 1)
            {
               writeMergedDocuments(doc, resp, printAction);
            }
            else
            {
               writeOriginalDocument(doc, resp, printAction);
            }
         }
      }
      catch (Throwable t)
      {
         LOG.warning("", t);
         throw t;
      }
   }
   
   /**
    * Writes the target document in the http output stream preserving its content type.
    * 
    * @param    doc
    *           The target document
    * @param    resp
    *           Provides output stream
    * @param    printAction
    *           The true value indicates a print request, otherwise a download file request.
    * 
    * @throws   IOException
    *           The exception if there is a failed output operation.
    */
   private void writeOriginalDocument(Document doc,
                                      HttpServletResponse resp,
                                      boolean printAction)
   throws IOException
   {
      byte[] binaryContent = doc.getBinaryContent();
      writeDocument(new ByteArrayInputStream(binaryContent),
                    binaryContent.length,
                    doc.getDocumentType(), 
                    doc.getDocumentFileName(),
                    resp,
                    printAction);
   }

   /**
    * Writes split content of the target document in a one merged pdf file.
    *
    * @param    doc
    *           The document with split content
    * @param    resp
    *           Provides output stream
    * @param    printAction
    *           The true value indicates a print request, otherwise a download file request.
    *
    * @throws   IOException
    *           The exception if there is a failed output operation.
    */
   private void writeMergedDocuments(Document doc, HttpServletResponse resp, boolean printAction)
   throws IOException
   {
      String fileName = doc.getDocumentFileName();
      DocumentType docType = doc.getDocumentType();
      String ext = docType.getExtension();
      int index = fileName.lastIndexOf("." + ext);
      if (index != -1)
      {
         fileName = fileName.substring(0, index);
      }

      PDFMergerUtility pdfMerger = new PDFMergerUtility();

      File tempFile = File.createTempFile(fileName, ext);
      pdfMerger.setDestinationFileName(tempFile.getAbsolutePath());
      tempFile.deleteOnExit();

      for (byte[] content : doc.getSplittedContent())
      {
         pdfMerger.addSource(new ByteArrayInputStream(content));
      }
      pdfMerger.mergeDocuments(MemoryUsageSetting.setupMixed(MAX_BUFFER_MEMORY_BYTES));
      
      long startDeliver = System.currentTimeMillis();
      
      writeDocument(new FileInputStream(tempFile),
                    (int) tempFile.length(),
                    docType,
                    fileName,
                    resp,
                    printAction);
      
      LOG.info(fileName + " was delivered within " + (System.currentTimeMillis() - startDeliver) + "ms");
      
      tempFile.delete();
   }

   /**
    * Writes the document in the http output stream preserving its content type.
    *
    * @param    inputStream
    *           The input stream of the document.
    * @param    contentLength
    *           The length of the content in the input stream.
    * @param    docType
    *           The document type.
    * @param    fileName
    *           The name of the file to be written.
    * @param    resp
    *           The http response.
    * @param    printAction
    *           The true value indicates a print request, otherwise a download file request.
    *
    * @throws   IOException
    *           The exception if there is a failed output operation.
    */
   private void writeDocument(InputStream inputStream,
                              int contentLength,
                              DocumentType docType,
                              String fileName,
                              HttpServletResponse resp,
                              boolean printAction)
   throws IOException
   {
      if (inputStream == null || docType == null || fileName == null)
      {
         return;
      }
      
      resp.setContentType(docType.getMimeType());
      resp.setHeader( "Content-Disposition:", printAction ? "inline" : "attachment;filename=" + fileName);
      resp.setContentLength(contentLength);
      resp.setBufferSize(BUFFER_SIZE);

      ServletOutputStream outputStream = resp.getOutputStream();
      try
      {
         int data = 0;
         while ((data = inputStream.read()) != -1)
         {
            outputStream.write(data);
         }
      }
      finally
      {
         inputStream.close();
         outputStream.flush();
      }
   }
}