python/pakfire/repository/metadata.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 json
  23 import time
  24
  25 from pakfire.constants import *
  26
  27 class Metadata(object):
  28         def __init__(self, pakfire, index, metafile=None, metadata=None):
  29                 self.pakfire = pakfire
  30                 self.index = index
  31
  32                 self.filename = metafile
  33
  34                 # Place where we save the data.
  35                 self._data = {
  36                         "database" : None,
  37                         "revision" : int(time.time()),
  38                         "version"  : METADATA_FORMAT,
  39                 }
  40
  41                 # If a file was passed, we open it.
  42                 if self.filename:
  43                         self.open()
  44
  45                 # ... or parse the one that was passed.
  46                 elif metadata:
  47                         self.parse(metadata)
  48
  49         def __cmp__(self, other):
  50                 """
  51                         Compare two sets of metadata by their revision.
  52                 """
  53                 return cmp(self.revision, other.revision)
  54
  55         def parse(self, metadata):
  56                 try:
  57                         self._data = json.loads(metadata)
  58                 except:
  59                         raise # XXX catch json exceptions here
  60
  61         def open(self, filename=None):
  62                 """
  63                         Open a given file or use the default one and parse the
  64                         data in it.
  65                 """
  66                 if not filename:
  67                         filename = self.filename
  68
  69                 with open(filename) as f:
  70                         self.parse(f.read())
  71
  72         def save(self, filename=None):
  73                 """
  74                         Save all data to a file that could be exported to a
  75                         remote repository.
  76                 """
  77                 if not filename:
  78                         filename = self.filename
  79
  80                 f = open(filename, "w")
  81
  82                 # Write all data to the fileobj.
  83                 json.dump(self._data, f, indent=2)
  84
  85                 f.close()
  86
  87         @property
  88         def version(self):
  89                 """
  90                         Returns the version of the metadata.
  91                 """
  92                 return self._data.get("version")
  93
  94         @property
  95         def revision(self):
  96                 """
  97                         Returns the revision of the metadata.
  98                 """
  99                 return self._data.get("revision")
 100
 101         def get_database(self):
 102                 return self._data.get("database")
 103
 104         def set_database(self, val):
 105                 self._data["database"] = val
 106
 107         database = property(get_database, set_database)
 108
 109         def get_database_hash1(self):
 110                 return self._data.get("database_hash1", None)
 111
 112         def set_database_hash1(self, val):
 113                 self._data["database_hash1"] = val
 114
 115         database_hash1 = property(get_database_hash1, set_database_hash1)
 116
 117         def get_database_compression(self):
 118                 return self._data.get("database_compression", None)
 119
 120         def set_database_compression(self, val):
 121                 self._data["database_compression"] = val
 122
 123         database_compression = property(get_database_compression,
 124                 set_database_compression)