Synnefo

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import os

import types

from hashmap import HashMap

from binascii import hexlify, unhexlify

from cStringIO import StringIO

from client import Fault

def upload(client, path, container, prefix, name=None, mimetype=None):

    meta = client.retrieve_container_metadata(container)

    blocksize = int(meta['x-container-block-size'])

    blockhash = meta['x-container-block-hash']

    size = os.path.getsize(path)

    hashes = HashMap(blocksize, blockhash)

    hashes.load(open(path))

    map = {'bytes': size, 'hashes': [hexlify(x) for x in hashes]}

    objectname = name if name else os.path.split(path)[-1]

    object = prefix + objectname

    kwargs = {'mimetype':mimetype} if mimetype else {}

    v = None

    try:

        v = client.create_object_by_hashmap(container, object, map, **kwargs)

    except Fault, fault:

        if fault.status != 409:

            raise

    else:

        return v

    if type(fault.data) == types.StringType:

        missing = fault.data.split('\n')

    elif type(fault.data) == types.ListType:

        missing = fault.data

    if '' in missing:

        del missing[missing.index(''):]

    with open(path) as fp:

        for hash in missing:

            offset = hashes.index(unhexlify(hash)) * blocksize

            fp.seek(offset)

            block = fp.read(blocksize)

            client.update_container_data(container, StringIO(block))

    return client.create_object_by_hashmap(container, object, map, **kwargs)

def download(client, container, object, path):

    res = client.retrieve_object_hashmap(container, object)

    blocksize = int(res['block_size'])

    blockhash = res['block_hash']

    bytes = res['bytes']

    map = res['hashes']

    if os.path.exists(path):

        h = HashMap(blocksize, blockhash)

        h.load(open(path))

        hashes = [hexlify(x) for x in h]

    else:

        open(path, 'w').close()     # Create an empty file

        hashes = []

    with open(path, 'a+') as fp:

        if bytes != 0:

            for i, h in enumerate(map):

                if i < len(hashes) and h == hashes[i]:

                    continue

                start = i * blocksize

                end = '' if i == len(map) - 1 else ((i + 1) * blocksize) - 1

                data = client.retrieve_object(container, object, range='bytes=%s-%s' % (start, end))

                if i != len(map) - 1:

                    data += (blocksize - len(data)) * '\x00'

                fp.seek(start)

                fp.write(data)

        fp.truncate(bytes)