def __init__(self,
master_nodes,
name,
compress=True,
cache_size=None,
**kw):
super(Application, self).__init__(parseMasterList(master_nodes), name,
**kw)
# Internal Attributes common to all thread
self._db = None
self.primary_master_node = None
self.trying_master_node = None
# no self-assigned NID, primary master will supply us one
self._cache = ClientCache() if cache_size is None else \
ClientCache(max_size=cache_size)
self._loading_oid = None
self.new_oids = ()
self.last_oid = '\0' * 8
self.storage_event_handler = storage.StorageEventHandler(self)
self.storage_bootstrap_handler = storage.StorageBootstrapHandler(self)
self.storage_handler = storage.StorageAnswersHandler(self)
self.primary_handler = master.PrimaryAnswersHandler(self)
self.primary_bootstrap_handler = master.PrimaryBootstrapHandler(self)
self.notifications_handler = master.PrimaryNotificationsHandler(self)
self._txn_container = TransactionContainer()
# Lock definition :
# _load_lock is used to make loading and storing atomic
lock = Lock()
self._load_lock_acquire = lock.acquire
self._load_lock_release = lock.release
# _oid_lock is used in order to not call multiple oid
# generation at the same time
lock = Lock()
self._oid_lock_acquire = lock.acquire
self._oid_lock_release = lock.release
lock = Lock()
# _cache_lock is used for the client cache
self._cache_lock_acquire = lock.acquire
self._cache_lock_release = lock.release
# _connecting_to_master_node is used to prevent simultaneous master
# node connection attempts
self._connecting_to_master_node = Lock()
# same for storage nodes
self._connecting_to_storage_node = Lock()
self._node_failure_dict = {}
self.compress = getCompress(compress)
def __init__(self, app):
self.app = app
self.connection_dict = {}
# Define a lock in order to create one connection to
# a storage node at a time to avoid multiple connections
# to the same node.
self._lock = Lock()
self.node_failure_dict = {}
def __init__(self, master_nodes, name, compress=True, **kw):
super(Application, self).__init__(parseMasterList(master_nodes),
name, **kw)
# Internal Attributes common to all thread
self._db = None
self.cp = ConnectionPool(self)
self.primary_master_node = None
self.trying_master_node = None
# no self-assigned UUID, primary master will supply us one
self._cache = ClientCache()
self._loading_oid = None
self.new_oid_list = ()
self.last_oid = '\0' * 8
self.storage_event_handler = storage.StorageEventHandler(self)
self.storage_bootstrap_handler = storage.StorageBootstrapHandler(self)
self.storage_handler = storage.StorageAnswersHandler(self)
self.primary_handler = master.PrimaryAnswersHandler(self)
self.primary_bootstrap_handler = master.PrimaryBootstrapHandler(self)
self.notifications_handler = master.PrimaryNotificationsHandler( self)
self._txn_container = TransactionContainer()
# Lock definition :
# _load_lock is used to make loading and storing atomic
lock = Lock()
self._load_lock_acquire = lock.acquire
self._load_lock_release = lock.release
# _oid_lock is used in order to not call multiple oid
# generation at the same time
lock = Lock()
self._oid_lock_acquire = lock.acquire
self._oid_lock_release = lock.release
lock = Lock()
# _cache_lock is used for the client cache
self._cache_lock_acquire = lock.acquire
self._cache_lock_release = lock.release
# _connecting_to_master_node is used to prevent simultaneous master
# node connection attemps
self._connecting_to_master_node = Lock()
self.compress = compress
class Application(ThreadedApplication):
"""The client node application."""
def __init__(self, master_nodes, name, compress=True, **kw):
super(Application, self).__init__(parseMasterList(master_nodes),
name, **kw)
# Internal Attributes common to all thread
self._db = None
self.cp = ConnectionPool(self)
self.primary_master_node = None
self.trying_master_node = None
# no self-assigned UUID, primary master will supply us one
self._cache = ClientCache()
self._loading_oid = None
self.new_oid_list = ()
self.last_oid = '\0' * 8
self.storage_event_handler = storage.StorageEventHandler(self)
self.storage_bootstrap_handler = storage.StorageBootstrapHandler(self)
self.storage_handler = storage.StorageAnswersHandler(self)
self.primary_handler = master.PrimaryAnswersHandler(self)
self.primary_bootstrap_handler = master.PrimaryBootstrapHandler(self)
self.notifications_handler = master.PrimaryNotificationsHandler( self)
self._txn_container = TransactionContainer()
# Lock definition :
# _load_lock is used to make loading and storing atomic
lock = Lock()
self._load_lock_acquire = lock.acquire
self._load_lock_release = lock.release
# _oid_lock is used in order to not call multiple oid
# generation at the same time
lock = Lock()
self._oid_lock_acquire = lock.acquire
self._oid_lock_release = lock.release
lock = Lock()
# _cache_lock is used for the client cache
self._cache_lock_acquire = lock.acquire
self._cache_lock_release = lock.release
# _connecting_to_master_node is used to prevent simultaneous master
# node connection attemps
self._connecting_to_master_node = Lock()
self.compress = compress
def __getattr__(self, attr):
if attr in ('last_tid', 'pt'):
if self._connecting_to_master_node.locked():
if attr == 'last_tid':
return
else:
self._getMasterConnection()
return self.__getattribute__(attr)
def log(self):
super(Application, self).log()
logging.info("%r", self._cache)
@property
def txn_contexts(self):
# do not iter lazily to avoid race condition
return self._txn_container.values
def _waitAnyMessage(self, queue, block=True):
"""
Handle all pending packets.
block
If True (default), will block until at least one packet was
received.
"""
pending = self.dispatcher.pending
get = queue.get
_handlePacket = self._handlePacket
while pending(queue):
try:
conn, packet, kw = get(block)
except Empty:
break
if packet is None or isinstance(packet, ForgottenPacket):
# connection was closed or some packet was forgotten
continue
block = False
try:
_handlePacket(conn, packet, kw)
except ConnectionClosed:
pass
def _waitAnyTransactionMessage(self, txn_context, block=True):
"""
Just like _waitAnyMessage, but for per-transaction exchanges, rather
than per-thread.
"""
queue = txn_context['queue']
self.setHandlerData(txn_context)
try:
self._waitAnyMessage(queue, block=block)
finally:
# Don't leave access to thread context, even if a raise happens.
self.setHandlerData(None)
def _askStorage(self, conn, packet, **kw):
""" Send a request to a storage node and process its answer """
return self._ask(conn, packet, handler=self.storage_handler, **kw)
def _askPrimary(self, packet, **kw):
""" Send a request to the primary master and process its answer """
return self._ask(self._getMasterConnection(), packet,
handler=self.primary_handler, **kw)
def _getMasterConnection(self):
""" Connect to the primary master node on demand """
# For performance reasons, get 'master_conn' without locking.
result = self.master_conn
if result is None:
# If not connected, 'master_conn' must be tested again while we have
# the lock, to avoid concurrent threads reconnecting.
with self._connecting_to_master_node:
result = self.master_conn
if result is None:
self.new_oid_list = ()
result = self.master_conn = self._connectToPrimaryNode()
return result
def _connectToPrimaryNode(self):
"""
Lookup for the current primary master node
"""
logging.debug('connecting to primary master...')
self.start()
index = -1
ask = self._ask
handler = self.primary_bootstrap_handler
while 1:
# Get network connection to primary master
while 1:
if self.primary_master_node is not None:
# If I know a primary master node, pinpoint it.
self.trying_master_node = self.primary_master_node
self.primary_master_node = None
else:
# Otherwise, check one by one.
master_list = self.nm.getMasterList()
index = (index + 1) % len(master_list)
self.trying_master_node = master_list[index]
# Connect to master
conn = MTClientConnection(self,
self.notifications_handler,
node=self.trying_master_node,
dispatcher=self.dispatcher)
try:
ask(conn, Packets.RequestIdentification(
NodeTypes.CLIENT, self.uuid, None, self.name),
handler=handler)
except ConnectionClosed:
continue
# If we reached the primary master node, mark as connected
if self.primary_master_node is not None and \
self.primary_master_node is self.trying_master_node:
break
logging.info('Connected to %s', self.primary_master_node)
try:
# Request identification and required informations to be
# operational. Might raise ConnectionClosed so that the new
# primary can be looked-up again.
logging.info('Initializing from master')
ask(conn, Packets.AskNodeInformation(), handler=handler)
ask(conn, Packets.AskPartitionTable(), handler=handler)
ask(conn, Packets.AskLastTransaction(), handler=handler)
if self.pt.operational():
break
except ConnectionClosed:
logging.error('Connection to %s lost', self.trying_master_node)
self.primary_master_node = None
logging.info("Connected and ready")
return conn
def registerDB(self, db, limit):
self._db = db
def getDB(self):
return self._db
def new_oid(self):
"""Get a new OID."""
self._oid_lock_acquire()
try:
if not self.new_oid_list:
# Get new oid list from master node
# we manage a list of oid here to prevent
# from asking too many time new oid one by one
# from master node
self._askPrimary(Packets.AskNewOIDs(100))
if not self.new_oid_list:
raise NEOStorageError('new_oid failed')
self.last_oid = oid = self.new_oid_list.pop()
return oid
finally:
self._oid_lock_release()
def getObjectCount(self):
# return the last OID used, this is inaccurate
return int(u64(self.last_oid))
def load(self, oid, tid=None, before_tid=None):
"""
Internal method which manage load, loadSerial and loadBefore.
OID and TID (serial) parameters are expected packed.
oid
OID of object to get.
tid
If given, the exact serial at which OID is desired.
before_tid should be None.
before_tid
If given, the excluded upper bound serial at which OID is desired.
serial should be None.
Return value: (3-tuple)
- Object data (None if object creation was undone).
- Serial of given data.
- Next serial at which object exists, or None. Only set when tid
parameter is not None.
Exceptions:
NEOStorageError
technical problem
NEOStorageNotFoundError
object exists but no data satisfies given parameters
NEOStorageDoesNotExistError
object doesn't exist
NEOStorageCreationUndoneError
object existed, but its creation was undone
Note that loadSerial is used during conflict resolution to load
object's current version, which is not visible to us normaly (it was
committed after our snapshot was taken).
"""
# TODO:
# - rename parameters (here? and in handlers & packet definitions)
acquire = self._cache_lock_acquire
release = self._cache_lock_release
# XXX: Consider using a more fine-grained lock.
self._load_lock_acquire()
try:
acquire()
try:
result = self._loadFromCache(oid, tid, before_tid)
if result:
return result
self._loading_oid = oid
finally:
release()
# When not bound to a ZODB Connection, load() may be the
# first method called and last_tid may still be None.
# This happens, for example, when opening the DB.
if not (tid or before_tid) and self.last_tid:
# Do not get something more recent than the last invalidation
# we got from master.
before_tid = p64(u64(self.last_tid) + 1)
data, tid, next_tid, _ = self._loadFromStorage(oid, tid, before_tid)
acquire()
try:
if self._loading_oid:
# Common case (no race condition).
self._cache.store(oid, data, tid, next_tid)
elif self._loading_invalidated:
# oid has just been invalidated.
if not next_tid:
next_tid = self._loading_invalidated
self._cache.store(oid, data, tid, next_tid)
# Else, we just reconnected to the master.
finally:
release()
finally:
self._load_lock_release()
return data, tid, next_tid
def _loadFromStorage(self, oid, at_tid, before_tid):
packet = Packets.AskObject(oid, at_tid, before_tid)
for node, conn in self.cp.iterateForObject(oid, readable=True):
try:
tid, next_tid, compression, checksum, data, data_tid \
= self._askStorage(conn, packet)
except ConnectionClosed:
continue
if data or checksum != ZERO_HASH:
if checksum != makeChecksum(data):
logging.error('wrong checksum from %s for oid %s',
conn, dump(oid))
continue
return (decompress(data) if compression else data,
tid, next_tid, data_tid)
raise NEOStorageCreationUndoneError(dump(oid))
raise NEOStorageError("storage down or corrupted data")
def _loadFromCache(self, oid, at_tid=None, before_tid=None):
"""
Load from local cache, return None if not found.
"""
if at_tid:
result = self._cache.load(oid, at_tid + '*')
assert not result or result[1] == at_tid
return result
return self._cache.load(oid, before_tid)
def tpc_begin(self, transaction, tid=None, status=' '):
"""Begin a new transaction."""
# First get a transaction, only one is allowed at a time
txn_context = self._txn_container.new(transaction)
# use the given TID or request a new one to the master
answer_ttid = self._askPrimary(Packets.AskBeginTransaction(tid))
if answer_ttid is None:
raise NEOStorageError('tpc_begin failed')
assert tid in (None, answer_ttid), (tid, answer_ttid)
txn_context['ttid'] = answer_ttid
def store(self, oid, serial, data, version, transaction):
"""Store object."""
logging.debug('storing oid %s serial %s', dump(oid), dump(serial))
self._store(self._txn_container.get(transaction), oid, serial, data)
def _store(self, txn_context, oid, serial, data, data_serial=None,
unlock=False):
ttid = txn_context['ttid']
if data is None:
# This is some undo: either a no-data object (undoing object
# creation) or a back-pointer to an earlier revision (going back to
# an older object revision).
compressed_data = ''
compression = 0
checksum = ZERO_HASH
else:
assert data_serial is None
size = len(data)
if self.compress:
compressed_data = compress(data)
if size < len(compressed_data):
compressed_data = data
compression = 0
else:
compression = 1
else:
compression = 0
compressed_data = data
checksum = makeChecksum(compressed_data)
txn_context['data_size'] += size
on_timeout = partial(
self.onStoreTimeout,
txn_context=txn_context,
oid=oid,
)
# Store object in tmp cache
txn_context['data_dict'][oid] = data
# Store data on each node
txn_context['object_stored_counter_dict'][oid] = {}
txn_context['object_base_serial_dict'].setdefault(oid, serial)
txn_context['object_serial_dict'][oid] = serial
queue = txn_context['queue']
involved_nodes = txn_context['involved_nodes']
add_involved_nodes = involved_nodes.add
packet = Packets.AskStoreObject(oid, serial, compression,
checksum, compressed_data, data_serial, ttid, unlock)
for node, conn in self.cp.iterateForObject(oid):
try:
conn.ask(packet, on_timeout=on_timeout, queue=queue)
add_involved_nodes(node)
except ConnectionClosed:
continue
if not involved_nodes:
raise NEOStorageError("Store failed")
while txn_context['data_size'] >= self._cache._max_size:
self._waitAnyTransactionMessage(txn_context)
self._waitAnyTransactionMessage(txn_context, False)
def onStoreTimeout(self, conn, msg_id, txn_context, oid):
# NOTE: this method is called from poll thread, don't use
# thread-specific value !
txn_context.setdefault('timeout_dict', {})[oid] = msg_id
# Ask the storage if someone locks the object.
# By sending a message with a smaller timeout,
# the connection will be kept open.
conn.ask(Packets.AskHasLock(txn_context['ttid'], oid),
timeout=5, queue=txn_context['queue'])
def _handleConflicts(self, txn_context, tryToResolveConflict):
result = []
append = result.append
# Check for conflicts
data_dict = txn_context['data_dict']
object_base_serial_dict = txn_context['object_base_serial_dict']
object_serial_dict = txn_context['object_serial_dict']
conflict_serial_dict = txn_context['conflict_serial_dict'].copy()
txn_context['conflict_serial_dict'].clear()
resolved_conflict_serial_dict = txn_context[
'resolved_conflict_serial_dict']
for oid, conflict_serial_set in conflict_serial_dict.iteritems():
conflict_serial = max(conflict_serial_set)
serial = object_serial_dict[oid]
if ZERO_TID in conflict_serial_set:
if 1:
# XXX: disable deadlock avoidance code until it is fixed
logging.info('Deadlock avoidance on %r:%r',
dump(oid), dump(serial))
# 'data' parameter of ConflictError is only used to report the
# class of the object. It doesn't matter if 'data' is None
# because the transaction is too big.
try:
data = data_dict[oid]
except KeyError:
data = txn_context['cache_dict'][oid]
else:
# Storage refused us from taking object lock, to avoid a
# possible deadlock. TID is actually used for some kind of
# "locking priority": when a higher value has the lock,
# this means we stored objects "too late", and we would
# otherwise cause a deadlock.
# To recover, we must ask storages to release locks we
# hold (to let possibly-competing transactions acquire
# them), and requeue our already-sent store requests.
# XXX: currently, brute-force is implemented: we send
# object data again.
# WARNING: not maintained code
logging.info('Deadlock avoidance triggered on %r:%r',
dump(oid), dump(serial))
for store_oid, store_data in data_dict.iteritems():
store_serial = object_serial_dict[store_oid]
if store_data is CHECKED_SERIAL:
self._checkCurrentSerialInTransaction(txn_context,
store_oid, store_serial)
else:
if store_data is None:
# Some undo
logging.warning('Deadlock avoidance cannot reliably'
' work with undo, this must be implemented.')
conflict_serial = ZERO_TID
break
self._store(txn_context, store_oid, store_serial,
store_data, unlock=True)
else:
continue
else:
data = data_dict.pop(oid)
if data is CHECKED_SERIAL:
raise ReadConflictError(oid=oid, serials=(conflict_serial,
serial))
# TODO: data can be None if a conflict happens during undo
if data:
txn_context['data_size'] -= len(data)
resolved_serial_set = resolved_conflict_serial_dict.setdefault(
oid, set())
if resolved_serial_set and conflict_serial <= max(
resolved_serial_set):
# A later serial has already been resolved, skip.
resolved_serial_set.update(conflict_serial_set)
continue
try:
new_data = tryToResolveConflict(oid, conflict_serial,
serial, data)
except ConflictError:
logging.info('Conflict resolution failed for '
'%r:%r with %r', dump(oid), dump(serial),
dump(conflict_serial))
else:
logging.info('Conflict resolution succeeded for '
'%r:%r with %r', dump(oid), dump(serial),
dump(conflict_serial))
# Mark this conflict as resolved
resolved_serial_set.update(conflict_serial_set)
# Base serial changes too, as we resolved a conflict
object_base_serial_dict[oid] = conflict_serial
# Try to store again
self._store(txn_context, oid, conflict_serial, new_data)
append(oid)
continue
# With recent ZODB, get_pickle_metadata (from ZODB.utils) does
# not support empty values, so do not pass 'data' in this case.
raise ConflictError(oid=oid, serials=(conflict_serial,
serial), data=data or None)
return result
def waitResponses(self, queue):
"""Wait for all requests to be answered (or their connection to be
detected as closed)"""
pending = self.dispatcher.pending
_waitAnyMessage = self._waitAnyMessage
while pending(queue):
_waitAnyMessage(queue)
def waitStoreResponses(self, txn_context, tryToResolveConflict):
result = []
append = result.append
resolved_oid_set = set()
update = resolved_oid_set.update
_handleConflicts = self._handleConflicts
queue = txn_context['queue']
conflict_serial_dict = txn_context['conflict_serial_dict']
pending = self.dispatcher.pending
_waitAnyTransactionMessage = self._waitAnyTransactionMessage
while pending(queue) or conflict_serial_dict:
# Note: handler data can be overwritten by _handleConflicts
# so we must set it for each iteration.
_waitAnyTransactionMessage(txn_context)
if conflict_serial_dict:
conflicts = _handleConflicts(txn_context,
tryToResolveConflict)
if conflicts:
update(conflicts)
# Check for never-stored objects, and update result for all others
for oid, store_dict in \
txn_context['object_stored_counter_dict'].iteritems():
if not store_dict:
logging.error('tpc_store failed')
raise NEOStorageError('tpc_store failed')
elif oid in resolved_oid_set:
append((oid, ResolvedSerial) if OLD_ZODB else oid)
return result
def tpc_vote(self, transaction, tryToResolveConflict):
"""Store current transaction."""
txn_context = self._txn_container.get(transaction)
result = self.waitStoreResponses(txn_context, tryToResolveConflict)
ttid = txn_context['ttid']
# Store data on each node
assert not txn_context['data_dict'], txn_context
packet = Packets.AskStoreTransaction(ttid, str(transaction.user),
str(transaction.description), dumps(transaction._extension),
txn_context['cache_dict'])
queue = txn_context['queue']
trans_nodes = []
for node, conn in self.cp.iterateForObject(ttid):
logging.debug("voting transaction %s on %s", dump(ttid),
dump(conn.getUUID()))
try:
conn.ask(packet, queue=queue)
except ConnectionClosed:
continue
trans_nodes.append(node)
# check at least one storage node accepted
if trans_nodes:
involved_nodes = txn_context['involved_nodes']
packet = Packets.AskVoteTransaction(ttid)
for node in involved_nodes.difference(trans_nodes):
conn = self.cp.getConnForNode(node)
if conn is not None:
try:
conn.ask(packet, queue=queue)
except ConnectionClosed:
pass
involved_nodes.update(trans_nodes)
self.waitResponses(queue)
txn_context['voted'] = None
# We must not go further if connection to master was lost since
# tpc_begin, to lower the probability of failing during tpc_finish.
if 'error' in txn_context:
raise NEOStorageError(txn_context['error'])
return result
logging.error('tpc_vote failed')
raise NEOStorageError('tpc_vote failed')
def tpc_abort(self, transaction):
"""Abort current transaction."""
txn_context = self._txn_container.pop(transaction)
if txn_context is None:
return
p = Packets.AbortTransaction(txn_context['ttid'])
# cancel transaction on all those nodes
nodes = map(self.cp.getConnForNode,
txn_context['involved_nodes'] |
txn_context['checked_nodes'])
nodes.append(self.master_conn)
for conn in nodes:
if conn is not None:
try:
conn.notify(p)
except ConnectionClosed:
pass
# We don't need to flush queue, as it won't be reused by future
# transactions (deleted on next line & indexed by transaction object
# instance).
self.dispatcher.forget_queue(txn_context['queue'], flush_queue=False)
def tpc_finish(self, transaction, tryToResolveConflict, f=None):
"""Finish current transaction
To avoid inconsistencies between several databases involved in the
same transaction, an IStorage implementation must do its best not to
fail in tpc_finish. In particular, making a transaction permanent
should ideally be as simple as switching a bit permanently.
In NEO, all the data (with the exception of the tid, simply because
it is not known yet) is already flushed on disk at the end on the vote.
During tpc_finish, all nodes storing the transaction metadata are asked
to commit by saving the new tid and flushing again: for SQL backends,
it's just an UPDATE of 1 cell. At last, the metadata is moved to
a final place so that the new transaction is readable, but this is
something that can always be replayed (during the verification phase)
if any failure happens.
"""
txn_container = self._txn_container
if 'voted' not in txn_container.get(transaction):
self.tpc_vote(transaction, tryToResolveConflict)
checked_list = []
self._load_lock_acquire()
try:
# Call finish on master
txn_context = txn_container.pop(transaction)
cache_dict = txn_context['cache_dict']
checked_list = [oid for oid, data in cache_dict.iteritems()
if data is CHECKED_SERIAL]
for oid in checked_list:
del cache_dict[oid]
ttid = txn_context['ttid']
p = Packets.AskFinishTransaction(ttid, cache_dict, checked_list)
try:
tid = self._askPrimary(p, cache_dict=cache_dict, callback=f)
assert tid
except ConnectionClosed:
tid = self._getFinalTID(ttid)
if not tid:
raise
return tid
finally:
self._load_lock_release()
def _getFinalTID(self, ttid):
try:
p = Packets.AskFinalTID(ttid)
while 1:
try:
tid = self._askPrimary(p)
break
except ConnectionClosed:
pass
if tid == MAX_TID:
while 1:
for _, conn in self.cp.iterateForObject(
ttid, readable=True):
try:
return self._askStorage(conn, p)
except ConnectionClosed:
pass
self._getMasterConnection()
elif tid:
return tid
except Exception:
logging.exception("Failed to get final tid for TXN %s",
dump(ttid))
def undo(self, undone_tid, txn, tryToResolveConflict):
txn_context = self._txn_container.get(txn)
txn_info, txn_ext = self._getTransactionInformation(undone_tid)
txn_oid_list = txn_info['oids']
# Regroup objects per partition, to ask a minimum set of storage.
partition_oid_dict = {}
for oid in txn_oid_list:
partition = self.pt.getPartition(oid)
try:
oid_list = partition_oid_dict[partition]
except KeyError:
oid_list = partition_oid_dict[partition] = []
oid_list.append(oid)
# Ask storage the undo serial (serial at which object's previous data
# is)
getCellList = self.pt.getCellList
getCellSortKey = self.cp.getCellSortKey
getConnForCell = self.cp.getConnForCell
queue = self._thread_container.queue
ttid = txn_context['ttid']
undo_object_tid_dict = {}
snapshot_tid = p64(u64(self.last_tid) + 1)
for partition, oid_list in partition_oid_dict.iteritems():
cell_list = getCellList(partition, readable=True)
# We do want to shuffle before getting one with the smallest
# key, so that all cells with the same (smallest) key has
# identical chance to be chosen.
shuffle(cell_list)
storage_conn = getConnForCell(min(cell_list, key=getCellSortKey))
storage_conn.ask(Packets.AskObjectUndoSerial(ttid,
snapshot_tid, undone_tid, oid_list),
queue=queue, undo_object_tid_dict=undo_object_tid_dict)
# Wait for all AnswerObjectUndoSerial. We might get OidNotFoundError,
# meaning that objects in transaction's oid_list do not exist any
# longer. This is the symptom of a pack, so forbid undoing transaction
# when it happens.
try:
self.waitResponses(queue)
except NEOStorageNotFoundError:
self.dispatcher.forget_queue(queue)
raise UndoError('non-undoable transaction')
# Send undo data to all storage nodes.
for oid in txn_oid_list:
current_serial, undo_serial, is_current = undo_object_tid_dict[oid]
if is_current:
data = None
else:
# Serial being undone is not the latest version for this
# object. This is an undo conflict, try to resolve it.
try:
# Load the latest version we are supposed to see
data = self.load(oid, current_serial)[0]
# Load the version we were undoing to
undo_data = self.load(oid, undo_serial)[0]
except NEOStorageNotFoundError:
raise UndoError('Object not found while resolving undo '
'conflict')
# Resolve conflict
try:
data = tryToResolveConflict(oid, current_serial,
undone_tid, undo_data, data)
except ConflictError:
raise UndoError('Some data were modified by a later ' \
'transaction', oid)
undo_serial = None
self._store(txn_context, oid, current_serial, data, undo_serial)
return None, txn_oid_list
def _insertMetadata(self, txn_info, extension):
for k, v in loads(extension).items():
txn_info[k] = v
def _getTransactionInformation(self, tid):
packet = Packets.AskTransactionInformation(tid)
for node, conn in self.cp.iterateForObject(tid, readable=True):
try:
txn_info, txn_ext = self._askStorage(conn, packet)
except ConnectionClosed:
continue
except NEOStorageNotFoundError:
# TID not found
continue
break
else:
raise NEOStorageError('Transaction %r not found' % (tid, ))
return (txn_info, txn_ext)
def undoLog(self, first, last, filter=None, block=0):
# XXX: undoLog is broken
if last < 0:
# See FileStorage.py for explanation
last = first - last
# First get a list of transactions from all storage nodes.
# Each storage node will return TIDs only for UP_TO_DATE state and
# FEEDING state cells
queue = self._thread_container.queue
packet = Packets.AskTIDs(first, last, INVALID_PARTITION)
tid_set = set()
for storage_node in self.pt.getNodeSet(True):
conn = self.cp.getConnForNode(storage_node)
if conn is None:
continue
conn.ask(packet, queue=queue, tid_set=tid_set)
# Wait for answers from all storages.
self.waitResponses(queue)
# Reorder tids
ordered_tids = sorted(tid_set, reverse=True)
logging.debug("UndoLog tids %s", map(dump, ordered_tids))
# For each transaction, get info
undo_info = []
append = undo_info.append
for tid in ordered_tids:
(txn_info, txn_ext) = self._getTransactionInformation(tid)
if filter is None or filter(txn_info):
txn_info.pop('packed')
txn_info.pop("oids")
self._insertMetadata(txn_info, txn_ext)
append(txn_info)
if len(undo_info) >= last - first:
break
# Check we return at least one element, otherwise call
# again but extend offset
if len(undo_info) == 0 and not block:
undo_info = self.undoLog(first=first, last=last*5, filter=filter,
block=1)
return undo_info
def transactionLog(self, start, stop, limit):
tid_list = []
# request a tid list for each partition
for offset in xrange(self.pt.getPartitions()):
p = Packets.AskTIDsFrom(start, stop, limit, offset)
for node, conn in self.cp.iterateForObject(offset, readable=True):
try:
r = self._askStorage(conn, p)
break
except ConnectionClosed:
pass
else:
raise NEOStorageError('transactionLog failed')
if r:
tid_list = list(heapq.merge(tid_list, r))
if len(tid_list) >= limit:
del tid_list[limit:]
stop = tid_list[-1]
# request transactions informations
txn_list = []
append = txn_list.append
tid = None
for tid in tid_list:
(txn_info, txn_ext) = self._getTransactionInformation(tid)
txn_info['ext'] = loads(txn_ext)
append(txn_info)
return (tid, txn_list)
def history(self, oid, size=1, filter=None):
# Get history informations for object first
packet = Packets.AskObjectHistory(oid, 0, size)
for node, conn in self.cp.iterateForObject(oid, readable=True):
try:
history_list = self._askStorage(conn, packet)
except ConnectionClosed:
continue
# Now that we have object informations, get txn informations
result = []
# history_list is already sorted descending (by the storage)
for serial, size in history_list:
txn_info, txn_ext = self._getTransactionInformation(serial)
# create history dict
txn_info.pop('id')
txn_info.pop('oids')
txn_info.pop('packed')
txn_info['tid'] = serial
txn_info['version'] = ''
txn_info['size'] = size
if filter is None or filter(txn_info):
result.append(txn_info)
self._insertMetadata(txn_info, txn_ext)
return result
def importFrom(self, source, start, stop, tryToResolveConflict,
preindex=None):
# TODO: The main difference with BaseStorage implementation is that
# preindex can't be filled with the result 'store' (tid only
# known after 'tpc_finish'. This method could be dropped if we
# implemented IStorageRestoreable (a wrapper around source would
# still be required for partial import).
if preindex is None:
preindex = {}
for transaction in source.iterator(start, stop):
tid = transaction.tid
self.tpc_begin(transaction, tid, transaction.status)
for r in transaction:
oid = r.oid
pre = preindex.get(oid)
self.store(oid, pre, r.data, r.version, transaction)
preindex[oid] = tid
conflicted = self.tpc_vote(transaction, tryToResolveConflict)
assert not conflicted, conflicted
real_tid = self.tpc_finish(transaction, tryToResolveConflict)
assert real_tid == tid, (real_tid, tid)
from .iterator import iterator
def sync(self):
self._askPrimary(Packets.Ping())
def pack(self, t):
tid = TimeStamp(*time.gmtime(t)[:5] + (t % 60, )).raw()
if tid == ZERO_TID:
raise NEOStorageError('Invalid pack time')
self._askPrimary(Packets.AskPack(tid))
# XXX: this is only needed to make ZODB unit tests pass.
# It should not be otherwise required (clients should be free to load
# old data as long as it is available in cache, event if it was pruned
# by a pack), so don't bother invalidating on other clients.
self._cache_lock_acquire()
try:
self._cache.clear()
finally:
self._cache_lock_release()
def getLastTID(self, oid):
return self.load(oid)[1]
def checkCurrentSerialInTransaction(self, oid, serial, transaction):
self._checkCurrentSerialInTransaction(
self._txn_container.get(transaction), oid, serial)
def _checkCurrentSerialInTransaction(self, txn_context, oid, serial):
ttid = txn_context['ttid']
txn_context['object_serial_dict'][oid] = serial
# Placeholders
queue = txn_context['queue']
txn_context['object_stored_counter_dict'][oid] = {}
# ZODB.Connection performs calls 'checkCurrentSerialInTransaction'
# after stores, and skips oids that have been succeessfully stored.
assert oid not in txn_context['cache_dict'], (oid, txn_context)
txn_context['data_dict'].setdefault(oid, CHECKED_SERIAL)
checked_nodes = txn_context['checked_nodes']
packet = Packets.AskCheckCurrentSerial(ttid, serial, oid)
for node, conn in self.cp.iterateForObject(oid):
try:
conn.ask(packet, queue=queue)
except ConnectionClosed:
continue
checked_nodes.add(node)
if not checked_nodes:
raise NEOStorageError("checkCurrent failed")
self._waitAnyTransactionMessage(txn_context, False)
