Synnefo

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from pithos.api.settings import PITHOS_BACKEND_STORAGE

from store_helpers import get_mapper

class Mapper(object):

    """Mapper.

       Required constructor parameters: mappath, namelen.

       Optional mappool.

    """

    def __init__(self, **params):

        fmap, rmap = get_mapper(PITHOS_BACKEND_STORAGE, **params)

        self.rmap = rmap

        self.fmap = fmap

    def map_retr(self, maphash, blkoff=0, nr=100000000000000):

        """Return as a list, part of the hashes map of an object

           at the given block offset.

           By default, return the whole hashes map.

        """

        if self.fmap:

            return self.fmap.map_retr(maphash, blkoff, nr)

        elif self.rmap:

            return self.rmap.map_retr(maphash, blkoff, nr)

    def map_stor(self, maphash, hashes=(), blkoff=0, create=1):

        """Store hashes in the given hashes map."""

        if self.rmap:

            return self.rmap.map_stor(maphash, hashes, blkoff, create)

        elif self.fmap:

            return self.fmap.map_stor(maphash, hashes, blkoff, create)