teichmann@535: #!/usr/bin/env python
teichmann@535: # -*- coding: UTF-8 -*-
teichmann@535: #
teichmann@535: # Copyright (C) 2011 by Intevation GmbH
teichmann@535: # Authors:
teichmann@535: # Sascha L. Teichmann <sascha.teichmann@intevation.de>
teichmann@535: #
teichmann@535: # This program is free software under the GPL (>=v2)
teichmann@535: # Read the file COPYING coming with the software for details.
teichmann@535: 
teichmann@535: import sys
teichmann@535: import os
teichmann@535: import re
teichmann@535: 
teichmann@535: import subprocess
teichmann@535: import logging
teichmann@535: 
teichmann@535: from heapq import nsmallest
teichmann@535: 
teichmann@535: from optparse import OptionParser
teichmann@535: 
teichmann@535: log = logging.getLogger(__name__) 
teichmann@535: log.setLevel(logging.WARNING)
teichmann@535: log.addHandler(logging.StreamHandler(sys.stderr))
teichmann@535: 
teichmann@535: DEFAULT_KEEP = 3
teichmann@535: 
teichmann@535: FIELD = re.compile("([a-zA-Z]+):\s*(.+)")
teichmann@535: 
teichmann@535: # map rich comparison to 'dpkg --compare-versions'
teichmann@535: # map == to !=, < to >= and so on to reverse order in heap. 
teichmann@535: RICH_CMP = dict([
teichmann@535:     ("__%s__" % a, lambda se, ot:
teichmann@535:         subprocess.call([
teichmann@535:             "dpkg", "--compare-versions", 
teichmann@535:             se.version, b, ot.version]) == 0)
teichmann@535:     for a, b in (("eq", "ne"), ("ne", "eq"),
teichmann@535:                  ("lt", "ge"), ("gt", "le"),
teichmann@535:                  ("le", "gt"), ("ge", "lt"))])
teichmann@535: 
teichmann@535: 
teichmann@535: class DebCmp(object):
teichmann@535:     """Helper class to make deb files comparable
teichmann@535:        by there versions.
teichmann@535:     """
teichmann@535: 
teichmann@535:     def __init__(self, version, path):
teichmann@535:         self.version = version
teichmann@535:         self.path    = path
teichmann@535: 
teichmann@535:         self.__dict__.update(RICH_CMP)
teichmann@535: 
teichmann@535: 
teichmann@535: def deb_info(deb, fields=["Package", "Version"]):
teichmann@535:     """Extract some meta info from a deb file."""
teichmann@535:     po = subprocess.Popen(
teichmann@535:         ["dpkg-deb", "-f", deb] + fields,
teichmann@535:         stdout=subprocess.PIPE)
teichmann@535:     out = po.communicate()[0]
teichmann@535:     return dict([m.groups()
teichmann@535:                 for m in map(FIELD.match, out.splitlines()) if m])
teichmann@535: 
teichmann@535: 
teichmann@535: def oldest_debs(deb_dir, keep=DEFAULT_KEEP):
teichmann@535:     """Given directory containing deb files this function 
teichmann@535:        returns the files that are older than the youngest 
teichmann@535:        keep-th per package.
teichmann@535:     """
teichmann@535: 
teichmann@535:     log.info("scanning dir '%s'" % deb_dir)
teichmann@535: 
teichmann@535:     packages = {}
teichmann@535: 
teichmann@535:     num = 1
teichmann@535:     for f in os.listdir(deb_dir):
teichmann@535:         if not f.endswith(".deb"): continue
teichmann@535:         deb = os.path.join(deb_dir, f)
teichmann@535:         if not os.path.isfile(deb): continue
teichmann@535:         info = deb_info(deb)
teichmann@535:         packages.setdefault(info['Package'], []).append(
teichmann@535:             DebCmp(info['Version'], deb))
teichmann@535:         if (num % 10) == 0:
teichmann@535:             log.info("%d debs found" % (num-1))
teichmann@535:         num += 1
teichmann@535: 
teichmann@535:     if log.isEnabledFor(logging.INFO):
teichmann@535:         log.info("%d debs found" % (num-1))
teichmann@535:         log.info("number packages: %s" % len(packages))
teichmann@535: 
teichmann@535:     for package, debs in packages.iteritems():
teichmann@535:         if len(debs) > keep:
teichmann@535:             # full sorting is not required
teichmann@535:             stay = frozenset([d.path for d in nsmallest(keep, debs)])
teichmann@535: 
teichmann@535:             for deb in debs:
teichmann@535:                 if deb.path not in stay:
teichmann@535:                     yield deb.path
teichmann@535: 
teichmann@535: 
teichmann@535: def main():
teichmann@535:     usage = "usage: %prog [options] dir ..."
teichmann@535:     parser = OptionParser(usage=usage)
teichmann@535:     parser.add_option(
teichmann@535:         "-v", "--verbose", action="store_true",
teichmann@535:         dest="verbose",
teichmann@535:         help="verbose output")
teichmann@535:     parser.add_option(
teichmann@535:         "-d", "--dry-run", action="store_true",
teichmann@535:         dest="dry_run",
teichmann@535:         help="don't remove the old deb files")
teichmann@535:     parser.add_option(
teichmann@535:         "-k", "--keep", action="store",
teichmann@535:         dest="keep", type="int", default=DEFAULT_KEEP,
teichmann@535:         help="number of files to keep. Default: %d" % DEFAULT_KEEP)
teichmann@535: 
teichmann@535:     options, args = parser.parse_args()
teichmann@535:     
teichmann@535:     remove = options.dry_run and (lambda x: None) or os.remove
teichmann@535:     keep   = max(1, options.keep)
teichmann@535:     if options.verbose: log.setLevel(logging.INFO)
teichmann@535: 
teichmann@535:     for deb_dir in args:
teichmann@535: 
teichmann@535:         if not os.path.isdir(deb_dir):
teichmann@535:             log.warn("'%s' is not a directory" % deb_dir)
teichmann@535:             continue
teichmann@535: 
teichmann@535:         for deb in oldest_debs(deb_dir, keep):
teichmann@535:             log.debug("remove '%s'" % deb)
teichmann@535:             remove(deb)
teichmann@535:             changes = deb.path[:-3] + "changes"
teichmann@535:             if os.path.isfile(changes):
teichmann@535:                 log.debug("remove '%s'" % changes)
teichmann@535:                 remove(changes)
teichmann@535: 
teichmann@535: 
teichmann@535: if __name__ == "__main__":
teichmann@535:     main()