root / snf-pithos-backend / pithos / backends / lib / hashfiler / store.py @ c30635bf
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# Copyright 2011-2012 GRNET S.A. All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or
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# without modification, are permitted provided that the following
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# conditions are met:
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#
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# 1. Redistributions of source code must retain the above
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# copyright notice, this list of conditions and the following
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# disclaimer.
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#
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# 2. Redistributions in binary form must reproduce the above
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# copyright notice, this list of conditions and the following
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# disclaimer in the documentation and/or other materials
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# provided with the distribution.
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#
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# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
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# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
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# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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# POSSIBILITY OF SUCH DAMAGE.
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#
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# The views and conclusions contained in the software and
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# documentation are those of the authors and should not be
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# interpreted as representing official policies, either expressed
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# or implied, of GRNET S.A.
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import os |
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from blocker import Blocker |
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from mapper import Mapper |
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class Store(object): |
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"""Store.
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Required constructor parameters: path, block_size, hash_algorithm, umask.
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"""
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def __init__(self, **params): |
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umask = params['umask']
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if umask is not None: |
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os.umask(umask) |
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path = params['path']
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if path and not os.path.exists(path): |
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os.makedirs(path) |
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if not os.path.isdir(path): |
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raise RuntimeError("Cannot open path '%s'" % (path,)) |
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p = {'blocksize': params['block_size'], |
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'blockpath': os.path.join(path + '/blocks'), |
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'hashtype': params['hash_algorithm']} |
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self.blocker = Blocker(**p)
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p = {'mappath': os.path.join(path + '/maps'), |
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'namelen': self.blocker.hashlen} |
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self.mapper = Mapper(**p)
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def map_get(self, name): |
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return self.mapper.map_retr(name) |
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def map_put(self, name, map): |
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self.mapper.map_stor(name, map) |
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def map_delete(self, name): |
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pass
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def block_get(self, hash): |
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blocks = self.blocker.block_retr((hash,)) |
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if not blocks: |
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return None |
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return blocks[0] |
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def block_put(self, data): |
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hashes, absent = self.blocker.block_stor((data,))
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return hashes[0] |
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def block_update(self, hash, offset, data): |
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h, e = self.blocker.block_delta(hash, offset, data) |
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return h
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def block_search(self, map): |
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return self.blocker.block_ping(map) |
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