Synnefo

# Copyright 2011-2012 GRNET S.A. All rights reserved.

#

# Redistribution and use in source and binary forms, with or

# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

#      copyright notice, this list of conditions and the following

#      disclaimer.

#

#   2. Redistributions in binary form must reproduce the above

#      copyright notice, this list of conditions and the following

#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

#

# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

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# The views and conclusions contained in the software and

# documentation are those of the authors and should not be

# interpreted as representing official policies, either expressed

# or implied, of GRNET S.A.

import sys

import uuid as uuidlib

import logging

import hashlib

import binascii

from functools import wraps, partial

from traceback import format_exc

try:

    from astakosclient import AstakosClient

except ImportError:

    AstakosClient = None

from base import (DEFAULT_ACCOUNT_QUOTA, DEFAULT_CONTAINER_QUOTA,

                  DEFAULT_CONTAINER_VERSIONING, NotAllowedError, QuotaError,

                  BaseBackend, AccountExists, ContainerExists, AccountNotEmpty,

                  ContainerNotEmpty, ItemNotExists, VersionNotExists,

                  InvalidHash, IllegalOperationError)

class DisabledAstakosClient(object):

    def __init__(self, *args, **kwargs):

        self.args = args

        self.kwargs = kwargs

    def __getattr__(self, name):

        m = ("AstakosClient has been disabled, "

             "yet an attempt to access it was made")

        raise AssertionError(m)

# Stripped-down version of the HashMap class found in tools.

class HashMap(list):

    def __init__(self, blocksize, blockhash):

        super(HashMap, self).__init__()

        self.blocksize = blocksize

        self.blockhash = blockhash

    def _hash_raw(self, v):

        h = hashlib.new(self.blockhash)

        h.update(v)

        return h.digest()

    def hash(self):

        if len(self) == 0:

            return self._hash_raw('')

        if len(self) == 1:

            return self.__getitem__(0)

        h = list(self)

        s = 2

        while s < len(h):

            s = s * 2

        h += [('\x00' * len(h[0]))] * (s - len(h))

        while len(h) > 1:

            h = [self._hash_raw(h[x] + h[x + 1]) for x in range(0, len(h), 2)]

        return h[0]

# Default modules and settings.

DEFAULT_DB_MODULE = 'pithos.backends.lib.sqlalchemy'

DEFAULT_DB_CONNECTION = 'sqlite:///backend.db'

DEFAULT_BLOCK_MODULE = 'pithos.backends.lib.hashfiler'

DEFAULT_BLOCK_PATH = 'data/'

DEFAULT_BLOCK_UMASK = 0o022

DEFAULT_BLOCK_SIZE = 4 * 1024 * 1024  # 4MB

DEFAULT_HASH_ALGORITHM = 'sha256'

#DEFAULT_QUEUE_MODULE = 'pithos.backends.lib.rabbitmq'

DEFAULT_BLOCK_PARAMS = {'mappool': None, 'blockpool': None}

#DEFAULT_QUEUE_HOSTS = '[amqp://guest:guest@localhost:5672]'

#DEFAULT_QUEUE_EXCHANGE = 'pithos'

DEFAULT_PUBLIC_URL_ALPHABET = ('0123456789'

                               'abcdefghijklmnopqrstuvwxyz'

                               'ABCDEFGHIJKLMNOPQRSTUVWXYZ')

DEFAULT_PUBLIC_URL_SECURITY = 16

QUEUE_MESSAGE_KEY_PREFIX = 'pithos.%s'

QUEUE_CLIENT_ID = 'pithos'

QUEUE_INSTANCE_ID = '1'

(CLUSTER_NORMAL, CLUSTER_HISTORY, CLUSTER_DELETED) = range(3)

inf = float('inf')

ULTIMATE_ANSWER = 42

DEFAULT_SOURCE = 'system'

DEFAULT_DISKSPACE_RESOURCE = 'pithos.diskspace'

logger = logging.getLogger(__name__)

def backend_method(func):

    @wraps(func)

    def wrapper(self, *args, **kw):

        # if we are inside a database transaction

        # just proceed with the method execution

        # otherwise manage a new transaction

        if self.in_transaction:

            return func(self, *args, **kw)

        try:

            self.pre_exec()

            result = func(self, *args, **kw)

            success_status = True

            return result

        except:

            success_status = False

            raise

        finally:

            self.post_exec(success_status)

    return wrapper

def debug_method(func):

    @wraps(func)

    def wrapper(self, *args, **kw):

        try:

            result = func(self, *args, **kw)

            return result

        except:

            result = format_exc()

            raise

        finally:

            all_args = map(repr, args)

            map(all_args.append, ('%s=%s' % (k, v) for k, v in kw.iteritems()))

            logger.debug(">>> %s(%s) <<< %s" % (

                func.__name__, ', '.join(all_args).rstrip(', '), result))

    return wrapper

def list_method(func):

    @wraps(func)

    def wrapper(self, *args, **kw):

        marker = kw.get('marker')

        limit = kw.get('limit')

        result = func(self, *args, **kw)

        start, limit = self._list_limits(result, marker, limit)

        return result[start:start + limit]

    return wrapper

class ModularBackend(BaseBackend):

    """A modular backend.

    Uses modules for SQL functions and storage.

    """

    def __init__(self, db_module=None, db_connection=None,

                 block_module=None, block_path=None, block_umask=None,

                 block_size=None, hash_algorithm=None,

                 queue_module=None, queue_hosts=None, queue_exchange=None,

                 astakos_auth_url=None, service_token=None,

                 astakosclient_poolsize=None,

                 free_versioning=True, block_params=None,

                 public_url_security=None,

                 public_url_alphabet=None,

                 account_quota_policy=None,

                 container_quota_policy=None,

                 container_versioning_policy=None):

        db_module = db_module or DEFAULT_DB_MODULE

        db_connection = db_connection or DEFAULT_DB_CONNECTION

        block_module = block_module or DEFAULT_BLOCK_MODULE

        block_path = block_path or DEFAULT_BLOCK_PATH

        block_umask = block_umask or DEFAULT_BLOCK_UMASK

        block_params = block_params or DEFAULT_BLOCK_PARAMS

        block_size = block_size or DEFAULT_BLOCK_SIZE

        hash_algorithm = hash_algorithm or DEFAULT_HASH_ALGORITHM

        #queue_module = queue_module or DEFAULT_QUEUE_MODULE

        account_quota_policy = account_quota_policy or DEFAULT_ACCOUNT_QUOTA

        container_quota_policy = container_quota_policy \

            or DEFAULT_CONTAINER_QUOTA

        container_versioning_policy = container_versioning_policy \

            or DEFAULT_CONTAINER_VERSIONING

        self.default_account_policy = {'quota': account_quota_policy}

        self.default_container_policy = {

            'quota': container_quota_policy,

            'versioning': container_versioning_policy

        }

        #queue_hosts = queue_hosts or DEFAULT_QUEUE_HOSTS

        #queue_exchange = queue_exchange or DEFAULT_QUEUE_EXCHANGE

        self.public_url_security = (public_url_security or

                                    DEFAULT_PUBLIC_URL_SECURITY)

        self.public_url_alphabet = (public_url_alphabet or

                                    DEFAULT_PUBLIC_URL_ALPHABET)

        self.hash_algorithm = hash_algorithm

        self.block_size = block_size

        self.free_versioning = free_versioning

        def load_module(m):

            __import__(m)

            return sys.modules[m]

        self.db_module = load_module(db_module)

        self.wrapper = self.db_module.DBWrapper(db_connection)

        params = {'wrapper': self.wrapper}

        self.permissions = self.db_module.Permissions(**params)

        self.config = self.db_module.Config(**params)

        self.commission_serials = self.db_module.QuotaholderSerial(**params)

        for x in ['READ', 'WRITE']:

            setattr(self, x, getattr(self.db_module, x))

        self.node = self.db_module.Node(**params)

        for x in ['ROOTNODE', 'SERIAL', 'NODE', 'HASH', 'SIZE', 'TYPE',

                  'MTIME', 'MUSER', 'UUID', 'CHECKSUM', 'CLUSTER',

                  'MATCH_PREFIX', 'MATCH_EXACT']:

            setattr(self, x, getattr(self.db_module, x))

        self.ALLOWED = ['read', 'write']

        self.block_module = load_module(block_module)

        self.block_params = block_params

        params = {'path': block_path,

                  'block_size': self.block_size,

                  'hash_algorithm': self.hash_algorithm,

                  'umask': block_umask}

        params.update(self.block_params)

        self.store = self.block_module.Store(**params)

        if queue_module and queue_hosts:

            self.queue_module = load_module(queue_module)

            params = {'hosts': queue_hosts,

                      'exchange': queue_exchange,

                      'client_id': QUEUE_CLIENT_ID}

            self.queue = self.queue_module.Queue(**params)

        else:

            class NoQueue:

                def send(self, *args):

                    pass

                def close(self):

                    pass

            self.queue = NoQueue()

        self.astakos_auth_url = astakos_auth_url

        self.service_token = service_token

        if not astakos_auth_url or not AstakosClient:

            self.astakosclient = DisabledAstakosClient(

                service_token, astakos_auth_url,

                use_pool=True,

                pool_size=astakosclient_poolsize)

        else:

            self.astakosclient = AstakosClient(

                service_token, astakos_auth_url,

                use_pool=True,

                pool_size=astakosclient_poolsize)

        self.serials = []

        self.messages = []

        self._move_object = partial(self._copy_object, is_move=True)

        self.lock_container_path = False

        self.in_transaction = False

    def pre_exec(self, lock_container_path=False):

        self.lock_container_path = lock_container_path

        self.wrapper.execute()

        self.serials = []

        self.in_transaction = True

    def post_exec(self, success_status=True):

        if success_status:

            # send messages produced

            for m in self.messages:

                self.queue.send(*m)

            # register serials

            if self.serials:

                self.commission_serials.insert_many(

                    self.serials)

                # commit to ensure that the serials are registered

                # even if resolve commission fails

                self.wrapper.commit()

                # start new transaction

                self.wrapper.execute()

                r = self.astakosclient.resolve_commissions(

                    accept_serials=self.serials,

                    reject_serials=[])

                self.commission_serials.delete_many(

                    r['accepted'])

            self.wrapper.commit()

        else:

            if self.serials:

                r = self.astakosclient.resolve_commissions(

                    accept_serials=[],

                    reject_serials=self.serials)

                self.commission_serials.delete_many(

                    r['rejected'])

            self.wrapper.rollback()

        self.in_transaction = False

    def close(self):

        self.wrapper.close()

        self.queue.close()

    @property

    def using_external_quotaholder(self):

        return not isinstance(self.astakosclient, DisabledAstakosClient)

    @debug_method

    @backend_method

    @list_method

    def list_accounts(self, user, marker=None, limit=10000):

        """Return a list of accounts the user can access."""

        return self._allowed_accounts(user)

    def _get_account_quotas(self, account):

        """Get account usage from astakos."""

        quotas = self.astakosclient.service_get_quotas(account)[account]

        return quotas.get(DEFAULT_SOURCE, {}).get(DEFAULT_DISKSPACE_RESOURCE,

                                                  {})

    def _get_account_quotas(self, account):

        """Get account usage from astakos."""

        quotas = self.astakosclient.service_get_quotas(account)[account]

        return quotas.get(DEFAULT_SOURCE, {}).get(DEFAULT_DISKSPACE_RESOURCE,

                                                  {})

    @debug_method

    @backend_method

    def get_account_meta(self, user, account, domain, until=None,

                         include_user_defined=True):

        """Return a dictionary with the account metadata for the domain."""

        path, node = self._lookup_account(account, user == account)

        if user != account:

            if until or (node is None) or (account not

                                           in self._allowed_accounts(user)):

                raise NotAllowedError

        try:

            props = self._get_properties(node, until)

            mtime = props[self.MTIME]

        except NameError:

            props = None

            mtime = until

        count, bytes, tstamp = self._get_statistics(node, until, compute=True)

        tstamp = max(tstamp, mtime)

        if until is None:

            modified = tstamp

        else:

            modified = self._get_statistics(

                node, compute=True)[2]  # Overall last modification.

            modified = max(modified, mtime)

        if user != account:

            meta = {'name': account}

        else:

            meta = {}

            if props is not None and include_user_defined:

                meta.update(

                    dict(self.node.attribute_get(props[self.SERIAL], domain)))

            if until is not None:

                meta.update({'until_timestamp': tstamp})

            meta.update({'name': account, 'count': count, 'bytes': bytes})

            if self.using_external_quotaholder:

                external_quota = self._get_account_quotas(account)

                meta['bytes'] = external_quota.get('usage', 0)

        meta.update({'modified': modified})

        return meta

    @debug_method

    @backend_method

    def update_account_meta(self, user, account, domain, meta, replace=False):

        """Update the metadata associated with the account for the domain."""

        if user != account:

            raise NotAllowedError

        path, node = self._lookup_account(account, True)

        self._put_metadata(user, node, domain, meta, replace,

                           update_statistics_ancestors_depth=-1)

    @debug_method

    @backend_method

    def get_account_groups(self, user, account):

        """Return a dictionary with the user groups defined for the account."""

        if user != account:

            if account not in self._allowed_accounts(user):

                raise NotAllowedError

            return {}

        self._lookup_account(account, True)

        return self.permissions.group_dict(account)

    @debug_method

    @backend_method

    def update_account_groups(self, user, account, groups, replace=False):

        """Update the groups associated with the account."""

        if user != account:

            raise NotAllowedError

        self._lookup_account(account, True)

        self._check_groups(groups)

        if replace:

            self.permissions.group_destroy(account)

        for k, v in groups.iteritems():

            if not replace:  # If not already deleted.

                self.permissions.group_delete(account, k)

            if v:

                self.permissions.group_addmany(account, k, v)

    @debug_method

    @backend_method

    def get_account_policy(self, user, account):

        """Return a dictionary with the account policy."""

        if user != account:

            if account not in self._allowed_accounts(user):

                raise NotAllowedError

            return {}

        path, node = self._lookup_account(account, True)

        policy = self._get_policy(node, is_account_policy=True)

        if self.using_external_quotaholder:

            external_quota = self._get_account_quotas(account)

            policy['quota'] = external_quota.get('limit', 0)

        return policy

    @debug_method

    @backend_method

    def update_account_policy(self, user, account, policy, replace=False):

        """Update the policy associated with the account."""

        if user != account:

            raise NotAllowedError

        path, node = self._lookup_account(account, True)

        self._check_policy(policy, is_account_policy=True)

        self._put_policy(node, policy, replace, is_account_policy=True)

    @debug_method

    @backend_method

    def put_account(self, user, account, policy=None):

        """Create a new account with the given name."""

        policy = policy or {}

        if user != account:

            raise NotAllowedError

        node = self.node.node_lookup(account)

        if node is not None:

            raise AccountExists('Account already exists')

        if policy:

            self._check_policy(policy, is_account_policy=True)

        node = self._put_path(user, self.ROOTNODE, account,

                              update_statistics_ancestors_depth=-1)

        self._put_policy(node, policy, True, is_account_policy=True)

    @debug_method

    @backend_method

    def delete_account(self, user, account):

        """Delete the account with the given name."""

        if user != account:

            raise NotAllowedError

        node = self.node.node_lookup(account)

        if node is None:

            return

        if not self.node.node_remove(node,

                                     update_statistics_ancestors_depth=-1):

            raise AccountNotEmpty('Account is not empty')

        self.permissions.group_destroy(account)

    @debug_method

    @backend_method

    @list_method

    def list_containers(self, user, account, marker=None, limit=10000,

                        shared=False, until=None, public=False):

        """Return a list of containers existing under an account."""

        if user != account:

            if until or account not in self._allowed_accounts(user):

                raise NotAllowedError

            return self._allowed_containers(user, account)

        if shared or public:

            allowed = set()

            if shared:

                allowed.update([x.split('/', 2)[1] for x in

                               self.permissions.access_list_shared(account)])

            if public:

                allowed.update([x[0].split('/', 2)[1] for x in

                               self.permissions.public_list(account)])

            return sorted(allowed)

        node = self.node.node_lookup(account)

        return [x[0] for x in self._list_object_properties(

            node, account, '', '/', marker, limit, False, None, [], until)]

    @debug_method

    @backend_method

    def list_container_meta(self, user, account, container, domain,

                            until=None):

        """Return a list of the container's object meta keys for a domain."""

        allowed = []

        if user != account:

            if until:

                raise NotAllowedError

            allowed = self.permissions.access_list_paths(

                user, '/'.join((account, container)))

            if not allowed:

                raise NotAllowedError

        path, node = self._lookup_container(account, container)

        before = until if until is not None else inf

        allowed = self._get_formatted_paths(allowed)

        return self.node.latest_attribute_keys(node, domain, before,

                                               CLUSTER_DELETED, allowed)

    @debug_method

    @backend_method

    def get_container_meta(self, user, account, container, domain, until=None,

                           include_user_defined=True):

        """Return a dictionary with the container metadata for the domain."""

        if user != account:

            if until or container not in self._allowed_containers(user,

                                                                  account):

                raise NotAllowedError

        path, node = self._lookup_container(account, container)

        props = self._get_properties(node, until)

        mtime = props[self.MTIME]

        count, bytes, tstamp = self._get_statistics(node, until)

        tstamp = max(tstamp, mtime)

        if until is None:

            modified = tstamp

        else:

            modified = self._get_statistics(

                node)[2]  # Overall last modification.

            modified = max(modified, mtime)

        if user != account:

            meta = {'name': container}

        else:

            meta = {}

            if include_user_defined:

                meta.update(

                    dict(self.node.attribute_get(props[self.SERIAL], domain)))

            if until is not None:

                meta.update({'until_timestamp': tstamp})

            meta.update({'name': container, 'count': count, 'bytes': bytes})

        meta.update({'modified': modified})

        return meta

    @debug_method

    @backend_method

    def update_container_meta(self, user, account, container, domain, meta,

                              replace=False):

        """Update the metadata associated with the container for the domain."""

        if user != account:

            raise NotAllowedError

        path, node = self._lookup_container(account, container)

        src_version_id, dest_version_id = self._put_metadata(

            user, node, domain, meta, replace,

            update_statistics_ancestors_depth=0)

        if src_version_id is not None:

            versioning = self._get_policy(

                node, is_account_policy=False)['versioning']

            if versioning != 'auto':

                self.node.version_remove(src_version_id,

                                         update_statistics_ancestors_depth=0)

    @debug_method

    @backend_method

    def get_container_policy(self, user, account, container):

        """Return a dictionary with the container policy."""

        if user != account:

            if container not in self._allowed_containers(user, account):

                raise NotAllowedError

            return {}

        path, node = self._lookup_container(account, container)

        return self._get_policy(node, is_account_policy=False)

    @debug_method

    @backend_method

    def update_container_policy(self, user, account, container, policy,

                                replace=False):

        """Update the policy associated with the container."""

        if user != account:

            raise NotAllowedError

        path, node = self._lookup_container(account, container)

        self._check_policy(policy, is_account_policy=False)

        self._put_policy(node, policy, replace, is_account_policy=False)

    @debug_method

    @backend_method

    def put_container(self, user, account, container, policy=None):

        """Create a new container with the given name."""

        policy = policy or {}

        if user != account:

            raise NotAllowedError

        try:

            path, node = self._lookup_container(account, container)

        except NameError:

            pass

        else:

            raise ContainerExists('Container already exists')

        if policy:

            self._check_policy(policy, is_account_policy=False)

        path = '/'.join((account, container))

        node = self._put_path(

            user, self._lookup_account(account, True)[1], path,

            update_statistics_ancestors_depth=-1)

        self._put_policy(node, policy, True, is_account_policy=False)

    @debug_method

    @backend_method

    def delete_container(self, user, account, container, until=None, prefix='',

                         delimiter=None):

        """Delete/purge the container with the given name."""

        if user != account:

            raise NotAllowedError

        path, node = self._lookup_container(account, container)

        if until is not None:

            hashes, size, serials = self.node.node_purge_children(

                node, until, CLUSTER_HISTORY,

                update_statistics_ancestors_depth=0)

            for h in hashes:

                self.store.map_delete(h)

            self.node.node_purge_children(node, until, CLUSTER_DELETED,

                                          update_statistics_ancestors_depth=0)

            if not self.free_versioning:

                self._report_size_change(

                    user, account, -size, {

                        'action': 'container purge',

                        'path': path,

                        'versions': ','.join(str(i) for i in serials)

                    }

                )

            return

        if not delimiter:

            if self._get_statistics(node)[0] > 0:

                raise ContainerNotEmpty('Container is not empty')

            hashes, size, serials = self.node.node_purge_children(

                node, inf, CLUSTER_HISTORY,

                update_statistics_ancestors_depth=0)

            for h in hashes:

                self.store.map_delete(h)

            self.node.node_purge_children(node, inf, CLUSTER_DELETED,

                                          update_statistics_ancestors_depth=0)

            self.node.node_remove(node, update_statistics_ancestors_depth=0)

            if not self.free_versioning:

                self._report_size_change(

                    user, account, -size, {

                        'action': 'container purge',

                        'path': path,

                        'versions': ','.join(str(i) for i in serials)

                    }

                )

        else:

            # remove only contents

            src_names = self._list_objects_no_limit(

                user, account, container, prefix='', delimiter=None,

                virtual=False, domain=None, keys=[], shared=False, until=None,

                size_range=None, all_props=True, public=False)

            paths = []

            for t in src_names:

                path = '/'.join((account, container, t[0]))

                node = t[2]

                if not self._exists(node):

                    continue

                src_version_id, dest_version_id = self._put_version_duplicate(

                    user, node, size=0, type='', hash=None, checksum='',

                    cluster=CLUSTER_DELETED,

                    update_statistics_ancestors_depth=1)

                del_size = self._apply_versioning(

                    account, container, src_version_id,

                    update_statistics_ancestors_depth=1)

                self._report_size_change(

                    user, account, -del_size, {

                        'action': 'object delete',

                        'path': path,

                        'versions': ','.join([str(dest_version_id)])})

                self._report_object_change(

                    user, account, path, details={'action': 'object delete'})

                paths.append(path)

            self.permissions.access_clear_bulk(paths)

    def _list_objects(self, user, account, container, prefix, delimiter,

                      marker, limit, virtual, domain, keys, shared, until,

                      size_range, all_props, public):

        if user != account and until:

            raise NotAllowedError

        objects = []

        if shared and public:

            # get shared first

            shared_paths = self._list_object_permissions(

                user, account, container, prefix, shared=True, public=False)

            if shared_paths:

                path, node = self._lookup_container(account, container)

                shared_paths = self._get_formatted_paths(shared_paths)

                objects = set(self._list_object_properties(

                    node, path, prefix, delimiter, marker, limit, virtual,

                    domain, keys, until, size_range, shared_paths, all_props))

            # get public

            objects |= set(self._list_public_object_properties(

                user, account, container, prefix, all_props))

            objects = list(objects)

            objects.sort(key=lambda x: x[0])

        elif public:

            objects = self._list_public_object_properties(

                user, account, container, prefix, all_props)

        else:

            allowed = self._list_object_permissions(

                user, account, container, prefix, shared, public=False)

            if shared and not allowed:

                return []

            path, node = self._lookup_container(account, container)

            allowed = self._get_formatted_paths(allowed)

            objects = self._list_object_properties(

                node, path, prefix, delimiter, marker, limit, virtual, domain,

                keys, until, size_range, allowed, all_props)

        # apply limits

        start, limit = self._list_limits(objects, marker, limit)

        return objects[start:start + limit]

    def _list_public_object_properties(self, user, account, container, prefix,

                                       all_props):

        public = self._list_object_permissions(

            user, account, container, prefix, shared=False, public=True)

        paths, nodes = self._lookup_objects(public)

        path = '/'.join((account, container))

        cont_prefix = path + '/'

        paths = [x[len(cont_prefix):] for x in paths]

        objects = [(p,) + props for p, props in

                   zip(paths, self.node.version_lookup_bulk(

                       nodes, all_props=all_props, order_by_path=True))]

        return objects

    def _list_objects_no_limit(self, user, account, container, prefix,

                               delimiter, virtual, domain, keys, shared, until,

                               size_range, all_props, public):

        objects = []

        while True:

            marker = objects[-1] if objects else None

            limit = 10000

            l = self._list_objects(

                user, account, container, prefix, delimiter, marker, limit,

                virtual, domain, keys, shared, until, size_range, all_props,

                public)

            objects.extend(l)

            if not l or len(l) < limit:

                break

        return objects

    def _list_object_permissions(self, user, account, container, prefix,

                                 shared, public):

        allowed = []

        path = '/'.join((account, container, prefix)).rstrip('/')

        if user != account:

            allowed = self.permissions.access_list_paths(user, path)

            if not allowed:

                raise NotAllowedError

        else:

            allowed = set()

            if shared:

                allowed.update(self.permissions.access_list_shared(path))

            if public:

                allowed.update(

                    [x[0] for x in self.permissions.public_list(path)])

            allowed = sorted(allowed)

            if not allowed:

                return []

        return allowed

    @debug_method

    @backend_method

    def list_objects(self, user, account, container, prefix='', delimiter=None,

                     marker=None, limit=10000, virtual=True, domain=None,

                     keys=None, shared=False, until=None, size_range=None,

                     public=False):

        """List (object name, object version_id) under a container."""

        keys = keys or []

        return self._list_objects(

            user, account, container, prefix, delimiter, marker, limit,

            virtual, domain, keys, shared, until, size_range, False, public)

    @debug_method

    @backend_method

    def list_object_meta(self, user, account, container, prefix='',

                         delimiter=None, marker=None, limit=10000,

                         virtual=True, domain=None, keys=None, shared=False,

                         until=None, size_range=None, public=False):

        """Return a list of metadata dicts of objects under a container."""

        keys = keys or []

        props = self._list_objects(

            user, account, container, prefix, delimiter, marker, limit,

            virtual, domain, keys, shared, until, size_range, True, public)

        objects = []

        for p in props:

            if len(p) == 2:

                objects.append({'subdir': p[0]})

            else:

                objects.append({

                    'name': p[0],

                    'bytes': p[self.SIZE + 1],

                    'type': p[self.TYPE + 1],

                    'hash': p[self.HASH + 1],

                    'version': p[self.SERIAL + 1],

                    'version_timestamp': p[self.MTIME + 1],

                    'modified': p[self.MTIME + 1] if until is None else None,

                    'modified_by': p[self.MUSER + 1],

                    'uuid': p[self.UUID + 1],

                    'checksum': p[self.CHECKSUM + 1]})

        return objects

    @debug_method

    @backend_method

    def list_object_permissions(self, user, account, container, prefix=''):

        """Return a list of paths enforce permissions under a container."""

        return self._list_object_permissions(user, account, container, prefix,

                                             True, False)

    @debug_method

    @backend_method

    def list_object_public(self, user, account, container, prefix=''):

        """Return a mapping of object paths to public ids under a container."""

        public = {}

        for path, p in self.permissions.public_list('/'.join((account,

                                                              container,

                                                              prefix))):

            public[path] = p

        return public

    @debug_method

    @backend_method

    def get_object_meta(self, user, account, container, name, domain,

                        version=None, include_user_defined=True):

        """Return a dictionary with the object metadata for the domain."""

        self._can_read(user, account, container, name)

        path, node = self._lookup_object(account, container, name)

        props = self._get_version(node, version)

        if version is None:

            modified = props[self.MTIME]

        else:

            try:

                modified = self._get_version(

                    node)[self.MTIME]  # Overall last modification.

            except NameError:  # Object may be deleted.

                del_props = self.node.version_lookup(

                    node, inf, CLUSTER_DELETED)

                if del_props is None:

                    raise ItemNotExists('Object does not exist')

                modified = del_props[self.MTIME]

        meta = {}

        if include_user_defined:

            meta.update(

                dict(self.node.attribute_get(props[self.SERIAL], domain)))

        meta.update({'name': name,

                     'bytes': props[self.SIZE],

                     'type': props[self.TYPE],

                     'hash': props[self.HASH],

                     'version': props[self.SERIAL],

                     'version_timestamp': props[self.MTIME],

                     'modified': modified,

                     'modified_by': props[self.MUSER],

                     'uuid': props[self.UUID],

                     'checksum': props[self.CHECKSUM]})

        return meta

    @debug_method

    @backend_method

    def update_object_meta(self, user, account, container, name, domain, meta,

                           replace=False):

        """Update object metadata for a domain and return the new version."""

        self._can_write(user, account, container, name)

        path, node = self._lookup_object(account, container, name,

                                         lock_container=True)

        src_version_id, dest_version_id = self._put_metadata(

            user, node, domain, meta, replace,

            update_statistics_ancestors_depth=1)

        self._apply_versioning(account, container, src_version_id,

                               update_statistics_ancestors_depth=1)

        return dest_version_id

    @debug_method

    @backend_method

    def get_object_permissions_bulk(self, user, account, container, names):

        """Return the action allowed on the object, the path

        from which the object gets its permissions from,

        along with a dictionary containing the permissions."""

        permissions_path = self._get_permissions_path_bulk(account, container,

                                                           names)

        access_objects = self.permissions.access_check_bulk(permissions_path,

                                                            user)

        #group_parents = access_objects['group_parents']

        nobject_permissions = {}

        cpath = '/'.join((account, container, ''))

        cpath_idx = len(cpath)

        for path in permissions_path:

            allowed = 1

            name = path[cpath_idx:]

            if user != account:

                try:

                    allowed = access_objects[path]

                except KeyError:

                    raise NotAllowedError

            access_dict, allowed = \

                self.permissions.access_get_for_bulk(access_objects[path])

            nobject_permissions[name] = (self.ALLOWED[allowed], path,

                                         access_dict)

        self._lookup_objects(permissions_path)

        return nobject_permissions

    @debug_method

    @backend_method

    def get_object_permissions(self, user, account, container, name):

        """Return the action allowed on the object, the path

        from which the object gets its permissions from,

        along with a dictionary containing the permissions."""

        allowed = 'write'

        permissions_path = self._get_permissions_path(account, container, name)

        if user != account:

            if self.permissions.access_check(permissions_path, self.WRITE,

                                             user):

                allowed = 'write'

            elif self.permissions.access_check(permissions_path, self.READ,

                                               user):

                allowed = 'read'

            else:

                raise NotAllowedError

        self._lookup_object(account, container, name)

        return (allowed,

                permissions_path,

                self.permissions.access_get(permissions_path))

    @debug_method

    @backend_method

    def update_object_permissions(self, user, account, container, name,

                                  permissions):

        """Update the permissions associated with the object."""

        if user != account:

            raise NotAllowedError

        path = self._lookup_object(account, container, name,

                                   lock_container=True)[0]

        self._check_permissions(path, permissions)

        try:

            self.permissions.access_set(path, permissions)

        except:

            raise ValueError

        else:

            self._report_sharing_change(user, account, path, {'members':

                                        self.permissions.access_members(path)})

    @debug_method

    @backend_method

    def get_object_public(self, user, account, container, name):

        """Return the public id of the object if applicable."""

        self._can_read(user, account, container, name)

        path = self._lookup_object(account, container, name)[0]

        p = self.permissions.public_get(path)

        return p

    @debug_method

    @backend_method

    def update_object_public(self, user, account, container, name, public):

        """Update the public status of the object."""

        self._can_write(user, account, container, name)

        path = self._lookup_object(account, container, name,

                                   lock_container=True)[0]

        if not public:

            self.permissions.public_unset(path)

        else:

            self.permissions.public_set(

                path, self.public_url_security, self.public_url_alphabet)

    @debug_method

    @backend_method

    def get_object_hashmap(self, user, account, container, name, version=None):

        """Return the object's size and a list with partial hashes."""

        self._can_read(user, account, container, name)

        path, node = self._lookup_object(account, container, name)

        props = self._get_version(node, version)

        if props[self.HASH] is None:

            return 0, ()

        if props[self.HASH].startswith('archip:'):

            hashmap = self.store.map_get_archipelago(props[self.HASH],

                                                     props[self.SIZE])

            return props[self.SIZE], [x for x in hashmap]

        else:

            hashmap = self.store.map_get(self._unhexlify_hash(

                props[self.HASH]))

            return props[self.SIZE], [binascii.hexlify(x) for x in hashmap]

    def _update_object_hash(self, user, account, container, name, size, type,

                            hash, checksum, domain, meta, replace_meta,

                            permissions, src_node=None, src_version_id=None,

                            is_copy=False, report_size_change=True):

        if permissions is not None and user != account:

            raise NotAllowedError

        self._can_write(user, account, container, name)

        if permissions is not None:

            path = '/'.join((account, container, name))

            self._check_permissions(path, permissions)

        account_path, account_node = self._lookup_account(account, True)

        container_path, container_node = self._lookup_container(

            account, container)

        path, node = self._put_object_node(

            container_path, container_node, name)

        pre_version_id, dest_version_id = self._put_version_duplicate(

            user, node, src_node=src_node, size=size, type=type, hash=hash,

            checksum=checksum, is_copy=is_copy,

            update_statistics_ancestors_depth=1)

        # Handle meta.

        if src_version_id is None:

            src_version_id = pre_version_id

        self._put_metadata_duplicate(

            src_version_id, dest_version_id, domain, node, meta, replace_meta)

        del_size = self._apply_versioning(account, container, pre_version_id,

                                          update_statistics_ancestors_depth=1)

        size_delta = size - del_size

        if size_delta > 0:

            # Check account quota.

            if not self.using_external_quotaholder:

                account_quota = long(self._get_policy(

                    account_node, is_account_policy=True)['quota'])

                account_usage = self._get_statistics(account_node,

                                                     compute=True)[1]

                if (account_quota > 0 and account_usage > account_quota):

                    raise QuotaError(

                        'Account quota exceeded: limit: %s, usage: %s' % (

                            account_quota, account_usage))

            # Check container quota.

            container_quota = long(self._get_policy(

                container_node, is_account_policy=False)['quota'])

            container_usage = self._get_statistics(container_node)[1]

            if (container_quota > 0 and container_usage > container_quota):

                # This must be executed in a transaction, so the version is

                # never created if it fails.

                raise QuotaError(

                    'Container quota exceeded: limit: %s, usage: %s' % (

                        container_quota, container_usage

                    )

                )

        if report_size_change:

            self._report_size_change(

                user, account, size_delta,

                {'action': 'object update', 'path': path,

                 'versions': ','.join([str(dest_version_id)])})

        if permissions is not None:

            self.permissions.access_set(path, permissions)

            self._report_sharing_change(

                user, account, path,

                {'members': self.permissions.access_members(path)})

        self._report_object_change(

            user, account, path,

            details={'version': dest_version_id, 'action': 'object update'})