~unity-2d-team/unity-2d/Shell-MultiMonitor

# 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 uuid

import pycassa

from pycassa.system_manager import (

    LEXICAL_UUID_TYPE,

    SystemManager,

    TIME_UUID_TYPE,

    )

from grackle.server.cassandra import workaround_1779

def create_schema(host, keyspace, clobber=False):

    mgr = SystemManager(host)

    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()

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 _parse_message(self, 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 add_message(self, archive_uuid, message):

        message_uuid = uuid.uuid4()

        message_date, message_dict = self._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,

            {message_date.astimezone(dateutil.tz.tzutc()): 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'),

            }

    def get_messages(self, archive_uuid, order, count, start):

        if order in ("date", "-date"):

            reversed = order[0] == '-'

        else:

            raise AssertionError("Unsupported order.")

        pairs = self.archive_messages.get(

            archive_uuid, column_count=count + 1,

            column_start=start, column_reversed=reversed).items()

        ids = [v for k, v in pairs]

        messages = self.messages.multiget(

            ids, columns=['date', 'from', 'subject'])

        actual_count = len(pairs)

        if len(pairs) > count:

            assert len(pairs) == count + 1

            actual_count -= 1

            next_memo = str(pairs[count][0])

        else:

            next_memo = None

        return (

            [self._format_message(messages[id]) for id in ids[:actual_count]],

            next_memo,

            )