python/pakfire/repository/cache.py

   1 #!/usr/bin/python
   2 ###############################################################################
   3 #                                                                             #
   4 # Pakfire - The IPFire package management system                              #
   5 # Copyright (C) 2011 Pakfire development team                                 #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 import os
  23 import stat
  24 import time
  25
  26 import pakfire.util as util
  27 from pakfire.constants import *
  28
  29 class RepositoryCache(object):
  30         """
  31                 An object that is able to cache all data that is loaded from a
  32                 remote repository.
  33         """
  34
  35         def __init__(self, pakfire, repo):
  36                 self.pakfire = pakfire
  37                 self.repo = repo
  38
  39                 self.__created = None
  40
  41         @property
  42         def created(self):
  43                 """
  44                         Tells us, if the cache was already created.
  45                 """
  46                 if self.__created is None:
  47                         self.__created = os.path.exists(self.path)
  48
  49                 return self.__created
  50
  51         @property
  52         def path(self):
  53                 return os.path.join(REPO_CACHE_DIR, self.pakfire.distro.release, \
  54                         self.repo.name, self.repo.arch)
  55
  56         def abspath(self, path, create=True):
  57                 if create:
  58                         self.create()
  59
  60                 return os.path.join(self.path, path)
  61
  62         def create(self):
  63                 """
  64                         Create all necessary directories.
  65                 """
  66                 # Do nothing, if the cache has already been created.
  67                 if self.created:
  68                         return
  69
  70                 for path in ("mirrors", "packages", "repodata"):
  71                         path = self.abspath(path, create=False)
  72
  73                         if not os.path.exists(path):
  74                                 os.makedirs(path)
  75
  76                 self.__created = True
  77
  78         def exists(self, filename):
  79                 """
  80                         Returns True if a file exists and False if it doesn't.
  81                 """
  82                 return os.path.exists(self.abspath(filename))
  83
  84         def age(self, filename):
  85                 """
  86                         Returns the age of a downloaded file in minutes.
  87                         i.e. the time from download until now.
  88                 """
  89                 if not self.exists(filename):
  90                         return None
  91
  92                 filename = self.abspath(filename)
  93
  94                 # Creation time of the file
  95                 ctime = os.stat(filename)[stat.ST_CTIME]
  96
  97                 return (time.time() - ctime) / 60
  98
  99         def open(self, filename, *args, **kwargs):
 100                 filename = self.abspath(filename)
 101
 102                 return open(filename, *args, **kwargs)
 103
 104         def verify(self, filename, hash1):
 105                 """
 106                         Return a bool that indicates if a file matches the given hash.
 107                 """
 108                 return util.calc_hash1(self.abspath(filename)) == hash1
 109
 110         def remove(self, filename):
 111                 """
 112                         Remove a file from cache.
 113                 """
 114                 if not self.exists(filename):
 115                         return
 116
 117                 filename = self.abspath(filename)
 118                 os.unlink(filename)
 119
 120         def destroy(self):
 121                 """
 122                         Remove all files from this cache.
 123                 """
 124                 if self.created:
 125                         util.rm(self.path)