1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
# Copyright (c) 2012 Canonical Ltd
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License along with this program. If not, see
# <http://www.gnu.org/licenses/>.
import datetime
import dateutil.tz
import email.parser
from email.utils import parsedate_tz
import logging
import time
import uuid
import pycassa
from pycassa.system_manager import (
LEXICAL_UUID_TYPE,
SystemManager,
TIME_UUID_TYPE,
)
from pycassa.util import convert_time_to_uuid
from grackle.cassandra import workaround_1779
def create_schema(host, keyspace, clobber=False, create_keyspace=False):
mgr = SystemManager(host)
if create_keyspace:
mgr.create_keyspace(keyspace, replication_factor=1)
if clobber:
for cf in mgr.get_keyspace_column_families(keyspace):
mgr.drop_column_family(keyspace, cf)
try:
workaround_1779(
mgr.create_column_family, keyspace, 'message',
key_validation_class=LEXICAL_UUID_TYPE)
workaround_1779(
mgr.create_column_family, keyspace, 'archive_message',
comparator_type=TIME_UUID_TYPE,
default_validation_class=LEXICAL_UUID_TYPE)
pass
finally:
mgr.close()
def _parse_message(message):
"""Get a date and dict of an RFC822 message."""
parsed = email.parser.Parser().parsestr(message)
message_dict = {}
for key in ('from', 'to', 'subject', 'message-id'):
value = parsed.get(key, None)
if value is not None:
message_dict[key] = value
date = parsed.get('date')
if date is not None:
try:
pdate = parsedate_tz(date)
date = datetime.datetime(
*pdate[:6],
tzinfo=dateutil.tz.tzoffset('', pdate[9]))
except ValueError:
pass
message_dict['date'] = date.isoformat() if date is not None else None
return date, message_dict
def _utc_datetime(dt):
return dt.astimezone(dateutil.tz.tzutc())
def _utc_timestamp(dt):
return time.mktime(_utc_datetime(dt).timetuple()) - time.timezone
def _utc_timeuuid(dt, lowest_val=True):
return convert_time_to_uuid(_utc_timestamp(dt), lowest_val)
def _cmp_timeuuid(a, b):
if a.time != b.time:
return cmp(a.time, b.time)
return cmp(a, b)
def _bound_timeuuid(a, b, max=False):
if a == '' or _cmp_timeuuid(b, a) == (1 if max else -1):
return b
return a
class CassandraConnection(object):
def __init__(self, keyspace, host):
self._keyspace = keyspace
self._host = host
self._connection = self._connect()
self.messages = self._column_family('message')
self.archive_messages = self._column_family('archive_message')
def _connect(self):
return pycassa.connect(self._keyspace, self._host)
def _column_family(self, name):
return pycassa.ColumnFamily(self._connection, name)
def add_message(self, archive_uuid, message):
message_uuid = uuid.uuid4()
message_date, message_dict = _parse_message(message)
message_dict['content'] = message
message_dict['date_created'] = (
datetime.datetime.utcnow().isoformat() + 'Z')
self.messages.insert(message_uuid, message_dict)
self.archive_messages.insert(
archive_uuid,
{_utc_timestamp(message_date): message_uuid})
logging.debug(
'Imported %s into %s'
% (message_dict.get('message-id', None), archive_uuid))
return message_uuid
def _format_message(self, message):
return {
'date': message.get('date'),
'from': message.get('from'),
'subject': message.get('subject'),
'message-id': message.get('message-id'),
}
def _trim(self, sequence, end):
"""Return the sequence with one of the ends trimmed.
:param end: if true, remove the last element. otherwise remove
the first.
"""
if end:
return sequence[:-1]
else:
return sequence[1:]
def get_messages(self, archive_uuid, order, count, memo, backward=False,
start_date=None, finish_date=None):
if order in ("date", "-date"):
reversed = order[0] == '-'
else:
raise AssertionError("Unsupported order.")
if memo != '':
memo = uuid.UUID(memo)
if backward:
start = ''
finish = memo
else:
start = memo
finish = ''
if start_date is not None:
start = _bound_timeuuid(
start, _utc_timeuuid(start_date, lowest_val=False), max=True)
if finish_date is not None:
finish = _bound_timeuuid(
finish, _utc_timeuuid(finish_date, lowest_val=False))
# Get up to n+1 messages from the memo: the last item of the
# previous batch (because that's where the memo starts) + this
# batch.
pairs = self.archive_messages.get(
archive_uuid, column_count=count + 1, column_start=start,
column_finish=finish, column_reversed=reversed).items()
if len(pairs) and memo and pairs[0][0] <= memo:
# The memo (from the previous batch) was included in the result.
# Trim it.
pairs = self._trim(pairs, False ^ backward)
elif len(pairs) > count:
# There was no memo in the result, so the n+1th element is
# unnecessary. Kill it.
pairs = self._trim(pairs, True ^ backward)
if len(pairs) == 0:
return (None, [], None)
assert 0 < len(pairs) <= count
# We've narrowed down the message references. Fetch the messages.
ids = [v for k, v in pairs]
messages = self.messages.multiget(
ids, columns=['date', 'from', 'subject', 'message-id'])
return (
str(pairs[0][0]),
[self._format_message(messages[id]) for id in ids],
str(pairs[-1][0]),
)
|