certmaster/minion/modules/copyfile.py

   1 # Copyright 2007, Red Hat, Inc
   2 # seth vidal
   3 #
   4 # This software may be freely redistributed under the terms of the GNU
   5 # general public license.
   6 #
   7 # You should have received a copy of the GNU General Public License
   8 # along with this program; if not, write to the Free Software
   9 # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  10
  11
  12 import sha
  13 import os
  14 import time
  15 import shutil
  16
  17 import func_module
  18
  19
  20 class CopyFile(func_module.FuncModule):
  21
  22     version = "0.0.1"
  23     api_version = "0.0.2"
  24     description = "Allows for smart copying of a file."
  25
  26     def _checksum_blob(self, blob):
  27         thissum = sha.new()
  28         thissum.update(blob)
  29         return thissum.hexdigest()
  30
  31     def checksum(self, thing):
  32
  33         CHUNK=2**16
  34         thissum = sha.new()
  35         if os.path.exists(thing):
  36             fo = open(thing, 'r', CHUNK)
  37             chunk = fo.read
  38             while chunk:
  39                 chunk = fo.read(CHUNK)
  40                 thissum.update(chunk)
  41             fo.close()
  42             del fo
  43         else:
  44             # assuming it's a string of some kind
  45             thissum.update(thing)
  46
  47         return thissum.hexdigest()
  48
  49
  50     def copyfile(self, filepath, filebuf, mode=0644, uid=0, gid=0, force=None):
  51         # -1 = problem file was not copied
  52         # 1 =  file was copied
  53         # 0 = file was not copied b/c file is unchanged
  54
  55
  56         # we should probably verify mode,uid,gid are valid as well
  57
  58         dirpath = os.path.dirname(filepath)
  59         if not os.path.exists(dirpath):
  60             os.makedirs(dirpath)
  61
  62         remote_sum = self._checksum_blob(filebuf.data)
  63         local_sum = 0
  64         if os.path.exists(filepath):
  65             local_sum = self.checksum(filepath)
  66
  67         if remote_sum != local_sum or force is not None:
  68             # back up the localone
  69             if os.path.exists(filepath):
  70                 if not self._backuplocal(filepath):
  71                     return -1
  72
  73             # do the new write
  74             try:
  75                 fo = open(filepath, 'w')
  76                 fo.write(filebuf.data)
  77                 fo.close()
  78                 del fo
  79             except (IOError, OSError), e:
  80                 # XXX logger output here
  81                 return -1
  82         else:
  83             return 0
  84
  85         # hmm, need to figure out proper exceptions -akl
  86         try:
  87             # we could intify the mode here if it's a string
  88             os.chmod(filepath, mode)
  89             os.chown(filepath, uid, gid)
  90         except (IOError, OSError), e:
  91             return -1
  92
  93         return 1
  94
  95     def _backuplocal(self, fn):
  96         """
  97         make a date-marked backup of the specified file,
  98         return True or False on success or failure
  99         """
 100         # backups named basename-YYYY-MM-DD@HH:MM~
 101         ext = time.strftime("%Y-%m-%d@%H:%M~", time.localtime(time.time()))
 102         backupdest = '%s.%s' % (fn, ext)
 103
 104         try:
 105             shutil.copy2(fn, backupdest)
 106         except shutil.Error, e:
 107             #XXX logger output here
 108             return False
 109         return True