migrate-data

#!/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 pithos.tools.lib.hashmap import HashMap

from 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 = 'postgresql://gss@127.0.0.1/pithos'
    db = 'sqlite:///migrate.db'
    
    dt = DataMigration(pithosdb, db)
    dt.execute()