package org.dspace.app.mediafilter;
/*
* $HeadURL: $
*
* Version: $Revision: $
*
* Date: $Date: $
*
* Copyright (c) 2002-2009, The DSpace Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the DSpace Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*/
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import org.apache.log4j.Logger;
import org.dspace.core.ConfigurationManager;
import org.dspace.core.Utils;
/**
* Text MediaFilter for PDF sources
*
* This filter produces extracted text suitable for building an index,
* but not for display to end users.
* It forks a process running the "pdftotext" program from the
* XPdf suite -- see http://www.foolabs.com/xpdf/
* This is a suite of open-source PDF tools that has been widely ported
* to Unix platforms and the ones we use (pdftoppm, pdftotext) even
* run on Win32.
*
* This was written for the FACADE project but it is not directly connected
* to any of the other FACADE-specific software. The FACADE UI expects
* to find thumbnail images for 3D PDFs generated by this filter.
*
* Requires DSpace config properties keys:
*
* xpdf.path.pdftotext -- path to "pdftotext" executable (required!)
*
* @author Larry Stone
* @see org.dspace.app.mediafilter.MediaFilter
*/
public class XPDF2Text extends MediaFilter
{
private static Logger log = Logger.getLogger(XPDF2Text.class);
// Command to get text from pdf; @infile@, @COMMAND@ are placeholders
private static final String XPDF_PDFTOTEXT_COMMAND[] =
{
"@COMMAND@", "-q", "-enc", "UTF-8", "@infile@", "-"
};
// executable path that comes from DSpace config at runtime.
private String pdftotextPath = null;
public String getFilteredName(String oldFilename)
{
return oldFilename + ".txt";
}
public String getBundleName()
{
return "TEXT";
}
public String getFormatString()
{
return "Text";
}
public String getDescription()
{
return "Extracted Text";
}
public InputStream getDestinationStream(InputStream sourceStream)
throws Exception
{
// get configured value for path to XPDF command:
if (pdftotextPath == null)
{
pdftotextPath = ConfigurationManager.getProperty("xpdf.path.pdftotext");
if (pdftotextPath == null)
throw new IllegalStateException("No value for key \"xpdf.path.pdftotext\" in DSpace configuration! Should be path to XPDF pdftotext executable.");
}
File sourceTmp = File.createTempFile("DSfilt",".pdf");
sourceTmp.deleteOnExit(); // extra insurance, we'll delete it here.
int status = -1;
try
{
// make local temp copy of source PDF since PDF tools
// require a file for random access.
// XXX fixme could optimize if we ever get an interface to grab asset *files*
OutputStream sto = new FileOutputStream(sourceTmp);
Utils.copy(sourceStream, sto);
sto.close();
sourceStream.close();
String pdfCmd[] = XPDF_PDFTOTEXT_COMMAND.clone();
pdfCmd[0] = pdftotextPath;
pdfCmd[4] = sourceTmp.toString();
log.debug("Running command: "+Arrays.deepToString(pdfCmd));
Process pdfProc = Runtime.getRuntime().exec(pdfCmd);
InputStream stdout = pdfProc.getInputStream();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
Utils.copy(new BufferedInputStream(stdout), baos);
stdout.close();
baos.close();
status = pdfProc.waitFor();
String msg = null;
if (status == 1)
msg = "pdftotext failed opening input: file="+sourceTmp.toString();
else if (status == 3)
msg = "pdftotext permission failure (perhaps copying of text from this document is not allowed - check PDF file's internal permissions): file="+sourceTmp.toString();
else if (status != 0)
msg = "pdftotext failed, maybe corrupt PDF? status="+String.valueOf(status);
if (msg != null)
{
log.error(msg);
throw new IOException(msg);
}
return new ByteArrayInputStream(baos.toByteArray());
}
catch (InterruptedException e)
{
log.error("Failed in pdftotext subprocess: ",e);
throw e;
}
finally
{
sourceTmp.delete();
if (status != 0)
log.error("PDF conversion proc failed, returns="+status+", file="+sourceTmp);
}
}
}