cvs2svn_lib/cvs_file_database.py

   1 # (Be in -*- python -*- mode.)
   2 #
   3 # ====================================================================
   4 # Copyright (c) 2000-2009 CollabNet.  All rights reserved.
   5 #
   6 # This software is licensed as described in the file COPYING, which
   7 # you should have received as part of this distribution.  The terms
   8 # are also available at http://subversion.tigris.org/license-1.html.
   9 # If newer versions of this license are posted there, you may use a
  10 # newer version instead, at your option.
  11 #
  12 # This software consists of voluntary contributions made by many
  13 # individuals.  For exact contribution history, see the revision
  14 # history and logs, available at http://cvs2svn.tigris.org/.
  15 # ====================================================================
  16
  17 """This module contains database facilities used by cvs2svn."""
  18
  19
  20 import cPickle
  21
  22 from cvs2svn_lib import config
  23 from cvs2svn_lib.common import DB_OPEN_READ
  24 from cvs2svn_lib.common import DB_OPEN_NEW
  25 from cvs2svn_lib.artifact_manager import artifact_manager
  26
  27
  28 class CVSFileDatabase:
  29   """A database to store CVSFile objects and retrieve them by their id."""
  30
  31   def __init__(self, mode):
  32     """Initialize an instance, opening database in MODE (where MODE is
  33     either DB_OPEN_NEW or DB_OPEN_READ)."""
  34
  35     self.mode = mode
  36
  37     # A map { id : CVSFile }
  38     self._cvs_files = {}
  39
  40     if self.mode == DB_OPEN_NEW:
  41       pass
  42     elif self.mode == DB_OPEN_READ:
  43       f = open(artifact_manager.get_temp_file(config.CVS_FILES_DB), 'rb')
  44       cvs_files = cPickle.load(f)
  45       for cvs_file in cvs_files:
  46         self._cvs_files[cvs_file.id] = cvs_file
  47     else:
  48       raise RuntimeError('Invalid mode %r' % self.mode)
  49
  50   def log_file(self, cvs_file):
  51     """Add CVS_FILE, a CVSFile instance, to the database."""
  52
  53     if self.mode == DB_OPEN_READ:
  54       raise RuntimeError('Cannot write items in mode %r' % self.mode)
  55
  56     self._cvs_files[cvs_file.id] = cvs_file
  57
  58   def itervalues(self):
  59     for value in self._cvs_files.itervalues():
  60       yield value
  61
  62   def get_file(self, id):
  63     """Return the CVSFile with the specified ID."""
  64
  65     return self._cvs_files[id]
  66
  67   def close(self):
  68     if self.mode == DB_OPEN_NEW:
  69       f = open(artifact_manager.get_temp_file(config.CVS_FILES_DB), 'wb')
  70       cPickle.dump(self._cvs_files.values(), f, -1)
  71       f.close()
  72
  73     self._cvs_files = None
  74
  75