2 caching_data.py - The module contains the CachingData class.
4 Copyright (c) 2012 Intra2net AG
5 Author: Plamen Dimitrov
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.
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.
17 import os, platform, tempfile
20 from mailbox_state import MailboxState
22 CACHE_FILENAME = "message_cache.dat"
24 STATISTICS_FILENAME = "statistics.txt"
27 """This class is responsible for the caching of data."""
30 # integer for version of the cache
32 # boolean flag which indicates fallback mode of the cache
33 fallback_to_date_header = None
34 # dictionary of usernames as keys and dictionaries as values
35 # the second dictionaries have unique mailbox keys and mailboxes as values
38 def __init__(self, fallback_mode):
39 # open data file or create one and initialize date if not found
41 cachefile = open(CACHE_FILENAME, 'rb')
42 cache_info, self.data = pickle.load(cachefile)
43 cache_info = cache_info.split(' ')
44 self.version = cache_info[0]
45 self.fallback_to_date_header = cache_info[1]
46 if(self.version != CACHE_VERSION):
47 raise IOError("Cache file has version %s and the script version is %s" % (self.version, CACHE_VERSION))
48 if(self.fallback_to_date_header != str(fallback_mode)):
49 raise IOError("Cache file date fallback mode setting is different than current settings")
50 logging.info("Cache file %s loaded", CACHE_FILENAME)
51 logging.info("%s users found.", len(self.data))
52 except (IOError, ValueError) as ex:
53 logging.warning("Couldn't load cache file %s: %s", CACHE_FILENAME, ex)
54 logging.warning("DELETING CACHE")
55 self.version = CACHE_VERSION
56 self.fallback_to_date_header = str(fallback_mode)
57 stored_cache_info = self.version + ' ' + self.fallback_to_date_header
59 with open(CACHE_FILENAME, 'wb') as cachefile:
60 pickle.dump((stored_cache_info, self.data), cachefile)
63 # create temporary file first
64 location = os.path.dirname(CACHE_FILENAME)
65 file_descriptor, tmpname = tempfile.mkstemp(dir=location)
67 cachefile = os.fdopen(file_descriptor, 'wb')
69 # prepare data based on a save flag
71 for user in self.data:
73 for box_key in self.data[user]:
74 if(self.data[user][box_key].needs_save):
75 saved_data[user][box_key] = self.data[user][box_key]
76 logging.debug("The mailbox %s will be saved.", saved_data[user][box_key].name)
77 if(len(saved_data[user])==0):
79 logging.debug("The user %s will not be saved.", user)
80 self.data = saved_data
81 # avoid test mode or cases where nothing needs saving
82 if(len(saved_data)==0):
88 stored_cache_info = self.version + ' ' + self.fallback_to_date_header
89 pickle.dump((stored_cache_info, self.data), cachefile)
90 logging.debug("%s users stored.", len(self.data))
92 # handle windows non-atomic rename
93 if(platform.system()=='Windows'):
94 if(os.path.exists(CACHE_FILENAME)):
96 os.unlink(CACHE_FILENAME)
98 os.rename(tmpname, CACHE_FILENAME)
100 # clean up temporary file
104 logging.info("Wrote cache file %s", CACHE_FILENAME)
106 def retrieve_cached_mailbox(self, name, uidvalidity, user):
107 """Retrieve a cached mailbox or create it."""
108 box_key = name.strip('"') + uidvalidity
109 if(user not in self.data):
111 logging.debug("New user %s cached.", user)
112 if(box_key not in self.data[user]):
113 self.data[user][box_key] = MailboxState(name, uidvalidity, user)
114 logging.debug("New mailbox %s cached.", box_key)
115 return self.data[user][box_key]
117 def report_conflicts(self):
118 """Write a date conflicts report in a file."""
119 with open(STATISTICS_FILENAME, 'w') as statsfile:
120 owner_total_conflicts = {}
121 owner_total_missing = {}
122 for user in self.data:
123 statsfile.write("user: %s\n" % user)
124 owner_total_conflicts[user] = 0
125 owner_total_missing[user] = 0
126 for box_key in self.data[user]:
127 owner_total_conflicts[user] += self.data[user][box_key].date_conflicts
128 owner_total_missing[user] += self.data[user][box_key].no_received_field
129 statsfile.write("date conflicts: %-15.15s missing header: %-15.15s mailbox: %s\n"\
130 % (self.data[user][box_key].date_conflicts,
131 self.data[user][box_key].no_received_field,
132 self.data[user][box_key].name))
133 statsfile.write("date conflicts: %-15.15s missing header: %-15.15s TOTAL \n\n"\
134 % (owner_total_conflicts[user], owner_total_missing[user]))