Synnefo » Pithos

#!/usr/bin/env python

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from binascii import hexlify

from sqlalchemy import Table

from sqlalchemy.sql import select

from pithos import settings

from pithos.backends.modular import ModularBackend

from lib.hashmap import HashMap

from lib.migrate import Migration, Cache

import os

class DataMigration(Migration):

    def __init__(self, pithosdb, db):

        Migration.__init__(self,  pithosdb)

        self.cache = Cache(db)

    def retrieve_files(self):

        # Loop for all available files.

        filebody = Table('filebody', self.metadata, autoload=True)

        s = select([filebody.c.storedfilepath])

        rp = self.conn.execute(s)

        path = rp.fetchone()

        while path:

            yield path

            path = rp.fetchone()

        rp.close()

    def execute(self):

        blocksize = self.backend.block_size

        blockhash = self.backend.hash_algorithm

        for (path,) in self.retrieve_files():

            map = HashMap(blocksize, blockhash)

            try:

                map.load(open(path))

            except Exception, e:

                print e

                continue

            hash = hexlify(map.hash())

            if hash != self.cache.get(path):

                missing = self.backend.blocker.block_ping(map) # XXX Backend hack...

                status = '[>] ' + path

                if missing:

                    status += ' - %d block(s) missing' % len(missing)

                    with open(path) as fp:

                        for h in missing:

                            offset = map.index(h) * blocksize

                            fp.seek(offset)

                            block = fp.read(blocksize)

                            self.backend.put_block(block)

                else:

                    status += ' - no blocks missing'

                self.cache.put(path, hash)

            else:

                status = '[-] ' + path

            print status

if __name__ == "__main__":

    pithosdb = ''

    db = 'sqlite:///migrate.db'

    dt = DataMigration(pithosdb, db)

    dt.execute()