nzb_sample_extract.py

#!/usr/bin/env python
# -*- coding: latin-1 -*-

# 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/>

""" Only leave everything related to the samples in the NZB file.
This are the .avi or .mkv files and sometimes par2 files. No new file
will be created if there is no sample data.

python nzb_sample_extract.py file1.nzb dir/file2.nzb
will create file1.nzb and file2.nzb with less data in ./samples in the
directory of file1.nzb and dir/file2.nzb respectively.

python nzb_sample_extract.py /home/user/nzbdir -o /home/user/samples
sets one output directory.

Changelog:
----------

0.1 (2011-12-24)
 - Initial version
0.2 (2012-01-18)
 - Made the regex more strict
 - A bit more documentation
0.3 (2012-01-23)
 - Added option for VOB samples
 - Refactoring bug fixed
 - Made the regex more strict
 - Option to limit the maximum size
"""

import os
import sys
import optparse
import re
import unittest

# for running the script directly from command line
sys.path.append(os.path.join(os.path.dirname(
                os.path.realpath(sys.argv[0])), '..', 'rescene'))

try:
    import nzb_utils
except ImportError:
    print("Can't import the nzb_utils module.")

def is_sample(file_name, is_vobsample=False):
    MATCH_SAMPLE = ".*(\.avi|\.mkv)((\.vol\d+\+\d+)?.par2)?$"
    MATCH_VOBSAMPLE = ".*(\.vob)((\.vol\d+\+\d+)?.par2)?$"

    if is_vobsample:
        match = MATCH_VOBSAMPLE
    else:
        match = MATCH_SAMPLE

    return re.match(match, file_name.lower())

def extract_sample(nzb_file, output_dir):
    sample_nzb = nzb_utils.empty_nzb_document()
    sample_found = False

    for file in nzb_utils.read_nzb(nzb_file):
        file_name = nzb_utils.parse_name(file.subject)

        if is_sample(file_name, options.vobsample):
            if int(options.max_size) > 0: # we need to check the size
                size = sum([seg.bytes for seg in file.segments])
                if int(options.max_size) < size:
                    continue # not a sample, skip it
            sample_found = True
            nzb_utils.add_file(sample_nzb, file)

    if sample_found:
        snzb_file = os.path.join(output_dir, os.path.basename(nzb_file))
        try:
            os.makedirs(os.path.dirname(snzb_file))
        except:
            pass
        with open(snzb_file, "w") as sample:
            sample.write(nzb_utils.get_xml(sample_nzb))

def main(options, args):
    def check_file(file):
        if file[-4:].lower() == ".nzb":
            if options.output_dir:
                output_dir = options.output_dir
            else:
                output_dir = os.path.join(os.path.dirname(file), "samples")
            extract_sample(file, output_dir)

    for element in args:
        if os.path.isdir(element):
            for file in os.listdir(element):
                check_file(file)
        elif os.path.isfile(element):
            check_file(element)
        else:
            print("Only existing files or directories are accepted.")

class TestRegex(unittest.TestCase):
    """ Code to test the correctness of the sample detection. """
    def test_avi_in_name(self):
        avi = ("[1080]-[FULL]-[#a.b.foreign@EFNet]-[ UCL.2010-2011.Play-Offs."
            "Salzburg.vs.Tel.Aviv.DUTCH.WS.PDTV.XviD-iFH ]-[03/97] \"ucl."
            "2010.2011.playoffs.salzburg.tel.aviv-ifh.r00\" yEnc (1/61)")

        file_name = nzb_utils.parse_name(avi)
        self.assertEqual(file_name,
                        "ucl.2010.2011.playoffs.salzburg.tel.aviv-ifh.r00")
        self.assertFalse(is_sample(file_name), "detected as sample")


if __name__ == '__main__':
    parser = optparse.OptionParser(
        usage="Usage: %prog [directories] [NZBs] [options]'\n"
        "This tool will create new NZB files with only the sample "
        "related data in the 'samples' subdir.\n",
        version="%prog 0.2 (2012-01-18)") # --help, --version

    parser.add_option("-o", dest="output_dir", metavar="DIRECTORY",
                    help="moves the new NZB files to DIRECTORY and a "
                    "'samples' subfolder will be used if not specified")
    parser.add_option("-v", "--vobsample", dest="vobsample",
                    help="only create NZBs for vobsamples",
                    action="store_true")
    parser.add_option("-s", dest="max_size", metavar="SIZE", default=-1,
                    help="the sample can be max SIZE bytes large")

    # no arguments given
    if len(sys.argv) < 2:
        print(parser.format_help())
    else:
        (options, args) = parser.parse_args()
        main(options, args)