Synnefo » Pithos

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import os

from blocker import Blocker

from mapper import Mapper

class Store(object):

    """Store.

       Required contstructor parameters: path, block_size, hash_algorithm.

    """

    def __init__(self, **params):

        path = params['path']

        if path and not os.path.exists(path):

            os.makedirs(path)

        if not os.path.isdir(path):

            raise RuntimeError("Cannot open path '%s'" % (path,))

        p = {'blocksize': params['block_size'],

             'blockpath': os.path.join(path + '/blocks'),

             'hashtype': params['hash_algorithm']}

        self.blocker = Blocker(**p)

        p = {'mappath': os.path.join(path + '/maps'),

             'namelen': self.blocker.hashlen}

        self.mapper = Mapper(**p)

    def map_get(self, name):

        return self.mapper.map_retr(name)

    def map_put(self, name, map):

        self.mapper.map_stor(name, map)

    def map_delete(self, name):

        pass

    def block_get(self, hash):

        blocks = self.blocker.block_retr((hash,))

        if not blocks:

            return None

        return blocks[0]

    def block_put(self, data):

        hashes, absent = self.blocker.block_stor((data,))

        return hashes[0]

    def block_update(self, hash, offset, data):

        h, e = self.blocker.block_delta(hash, ((offset, data),))

        return h

    def block_search(self, map):

        return self.blocker.block_ping(map)