Synnefo » ./kamaki

# Copyright 2012-2014 GRNET S.A. All rights reserved.

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import codecs

from logging import getLogger

log = getLogger(__name__)

class History(object):

    ignore_commands = ['config set', ]

    def __init__(self, filepath, token=None):

        self.filepath = filepath

        self.token = token

        self._limit = 0

        self.counter = 0

    def __getitem__(self, cmd_ids):

        with codecs.open(self.filepath, mode='r', encoding='utf-8') as f:

            try:

                lines = f.readlines()

                self.counter, cmd_list = int(lines[0]), lines[1:]

                return cmd_list[cmd_ids]

            except IndexError:

                return None

    @property

    def limit(self):

        return self._limit

    @limit.setter

    def limit(self, new_limit):

        new_limit = int(new_limit)

        if new_limit < 0:

            raise ValueError('Invalid history limit (%s)' % new_limit)

        old_limit, self._limit = self._limit, new_limit

        if self._limit and ((not old_limit) or (self._limit <= old_limit)):

            with codecs.open(self.filepath, mode='r', encoding='utf-8') as f:

                lines = f.readlines()

                self.counter = int(lines[0])

                old_len = len(lines[1:])

            if old_len > new_limit:

                self.counter += old_len - new_limit

                with codecs.open(

                        self.filepath, mode='w', encoding='utf-8') as f:

                    f.write('%s\n' % self.counter)

                    f.write(''.join(lines[old_len - new_limit + 1:]))

                    f.flush()

    @classmethod

    def _match(self, line, match_terms):

        if match_terms:

            return all(term in line for term in match_terms.split())

        return True

    def get(self, match_terms=None, limit=0):

        """DEPRECATED since 0.14"""

        limit = int(limit or 0)

        r = ['%s.\t%s' % (i + 1, line) for i, line in enumerate(self[:]) if (

                self._match(line, match_terms))]

        return r[- limit:]

    def add(self, line):

        line = '%s' % line or ''

        bline = [w.lower() for w in line.split() if not w.startswith('-')]

        for cmd in self.ignore_commands:

            cmds = [w.lower() for w in cmd.split()]

            if cmds == bline[1:len(cmds) + 1]:

                log.debug('History ignored a command of type "%s"' % cmd)

                return

        line = line.replace(self.token, '...') if self.token else line

        try:

            with codecs.open(self.filepath, mode='a+', encoding='utf-8') as f:

                f.write(line + '\n')

                f.flush()

            self.limit = self.limit

        except Exception as e:

            log.debug('Add history failed for "%s" (%s)' % (line, e))

    def empty(self):

        with open(self.filepath, 'w') as f:

            f.write('0\n')

            f.flush()

        self.counter = 0

    def clean(self):

        """DEPRECATED since version 0.14"""

        return self.empty()

    def retrieve(self, cmd_id):

        if not cmd_id:

            return None

        cmd_id = int(cmd_id)

        return self[cmd_id - (1 if cmd_id > 0 else 0)]