##############################################################################
#
# Copyright (c) 2007 Nexedi SA and Contributors. All Rights Reserved.
# Vincent Pelletier <vincent@nexedi.com>
#
# WARNING: This program as such is intended to be used by professional
# programmers who take the whole responsability of assessing all potential
# consequences resulting from its eventual inadequacies and bugs
# End users who are looking for a ready-to-use solution with commercial
# garantees and support are strongly adviced to contract a Free Software
# Service Company
#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
##############################################################################
import sys
import transaction
from DateTime import DateTime
from Shared.DC.ZRDB.Results import Results
from Shared.DC.ZRDB.DA import DatabaseError
from zLOG import LOG, TRACE, INFO, WARNING, ERROR, PANIC
from ZODB.POSException import ConflictError
from Products.CMFActivity.ActivityTool import (
Message, MESSAGE_NOT_EXECUTED, MESSAGE_EXECUTED, SkippedMessage)
from Products.CMFActivity.ActivityRuntimeEnvironment import (
DEFAULT_MAX_RETRY, ActivityRuntimeEnvironment)
from Queue import Queue, VALIDATION_ERROR_DELAY, VALID, INVALID_PATH
from Products.CMFActivity.Errors import ActivityFlushError
# TODO: Limit by size in bytes instead of number of rows.
MAX_MESSAGE_LIST_SIZE = 100
INVOKE_ERROR_STATE = -2
def sort_message_key(message):
# same sort key as in SQLBase.getMessageList
return message.line.priority, message.line.date, message.uid
_DequeueMessageException = Exception()
# sqltest_dict ({'condition_name': <render_function>}) defines how to render
# condition statements in the SQL query used by SQLBase.getMessageList
def sqltest_dict():
sqltest_dict = {}
no_quote_type = int, float, long
def _(name, column=None, op="="):
if column is None:
column = name
column_op = "%s %s " % (column, op)
def render(value, render_string):
if isinstance(value, no_quote_type):
return column_op + str(value)
if isinstance(value, DateTime):
value = value.toZone('UTC').ISO()
if isinstance(value, basestring):
return column_op + render_string(value)
assert op == "=", value
if value is None: # XXX: see comment in SQLBase._getMessageList
return column + " IS NULL"
for x in value:
if isinstance(x, no_quote_type):
render_string = str
elif isinstance(x, DateTime):
value = (x.toZone('UTC').ISO() for x in value)
return "%s IN (%s)" % (column, ', '.join(map(render_string, value)))
return "0"
sqltest_dict[name] = render
_('active_process_uid')
_('group_method_id')
_('method_id')
_('path')
_('processing')
_('processing_node')
_('serialization_tag')
_('tag')
_('retry')
_('to_date', column="date", op="<=")
_('uid')
return sqltest_dict
sqltest_dict = sqltest_dict()
class SQLBase(Queue):
"""
Define a set of common methods for SQL-based storage of activities.
"""
def initialize(self, activity_tool, clear):
folder = activity_tool.getPortalObject().portal_skins.activity
try:
createMessageTable = folder.SQLBase_createMessageTable
except AttributeError:
return
if clear:
folder.SQLBase_dropMessageTable(table=self.sql_table)
createMessageTable(table=self.sql_table)
else:
src = createMessageTable._upgradeSchema(create_if_not_exists=1,
initialize=self._initialize,
table=self.sql_table)
if src:
LOG('CMFActivity', INFO, "%r table upgraded\n%s"
% (self.sql_table, src))
def _initialize(self, db, column_list):
LOG('CMFActivity', ERROR, "Non-empty %r table upgraded."
" The following added columns could not be initialized: %s"
% (self.sql_table, ", ".join(column_list)))
def prepareQueueMessageList(self, activity_tool, message_list):
registered_message_list = [m for m in message_list if m.is_registered]
portal = activity_tool.getPortalObject()
for i in xrange(0, len(registered_message_list), MAX_MESSAGE_LIST_SIZE):
message_list = registered_message_list[i:i+MAX_MESSAGE_LIST_SIZE]
uid_list = portal.portal_ids.generateNewIdList(self.uid_group,
id_count=len(message_list), id_generator='uid')
path_list = ['/'.join(m.object_path) for m in message_list]
active_process_uid_list = [m.active_process_uid for m in message_list]
method_id_list = [m.method_id for m in message_list]
priority_list = [m.activity_kw.get('priority', 1) for m in message_list]
date_list = [m.activity_kw.get('at_date') for m in message_list]
group_method_id_list = [m.getGroupId() for m in message_list]
tag_list = [m.activity_kw.get('tag', '') for m in message_list]
serialization_tag_list = [m.activity_kw.get('serialization_tag', '')
for m in message_list]
processing_node_list = []
for m in message_list:
m.order_validation_text = x = self.getOrderValidationText(m)
processing_node_list.append(0 if x == 'none' else -1)
portal.SQLBase_writeMessageList(
table=self.sql_table,
uid_list=uid_list,
path_list=path_list,
active_process_uid_list=active_process_uid_list,
method_id_list=method_id_list,
priority_list=priority_list,
message_list=map(Message.dump, message_list),
group_method_id_list=group_method_id_list,
date_list=date_list,
tag_list=tag_list,
processing_node_list=processing_node_list,
serialization_tag_list=serialization_tag_list)
def getNow(self, context):
"""
Return the current value for SQL server's NOW().
Note that this value is not cached, and is not transactionnal on MySQL
side.
"""
result = context.SQLBase_getNow()
assert len(result) == 1
assert len(result[0]) == 1
return result[0][0]
def _getMessageList(self, activity_tool, offset=0, count=1000, src__=0, **kw):
# XXX: Because most columns have NOT NULL constraint, conditions with None
# value should be ignored, instead of trying to render them
# (with comparisons with NULL).
sql_connection = activity_tool.getPortalObject().cmf_activity_sql_connection
q = sql_connection.sql_quote__
if offset:
limit = '\nLIMIT %d,%d' % (offset, sys.maxint if count is None else count)
else:
limit = '' if count is None else '\nLIMIT %d' % count
sql = '\n AND '.join(sqltest_dict[k](v, q) for k, v in kw.iteritems())
sql = "SELECT * FROM %s%s\nORDER BY priority, date, uid%s" % (
self.sql_table, sql and '\nWHERE ' + sql, limit)
return sql if src__ else Results(sql_connection().query(sql, max_rows=0))
def getMessageList(self, *args, **kw):
result = self._getMessageList(*args, **kw)
if type(result) is str: # src__ == 1
return result,
class_name = self.__class__.__name__
return [Message.load(line.message,
activity=class_name,
uid=line.uid,
processing_node=line.processing_node,
retry=line.retry,
processing=line.processing)
for line in result]
def countMessage(self, activity_tool, tag=None, path=None,
method_id=None, message_uid=None, **kw):
"""Return the number of messages which match the given parameters.
"""
if isinstance(tag, str):
tag = [tag]
if isinstance(path, str):
path = [path]
if isinstance(method_id, str):
method_id = [method_id]
result = activity_tool.SQLBase_validateMessageList(table=self.sql_table,
method_id=method_id,
path=path,
message_uid=message_uid,
tag=tag,
serialization_tag=None,
count=1)
return result[0].uid_count
def hasActivity(self, activity_tool, object, method_id=None, only_valid=None,
active_process_uid=None,
only_invalid=False):
hasMessage = getattr(activity_tool, 'SQLBase_hasMessage', None)
if hasMessage is not None:
if object is None:
path = None
else:
path = '/'.join(object.getPhysicalPath())
try:
result = hasMessage(table=self.sql_table, path=path, method_id=method_id,
only_valid=only_valid, active_process_uid=active_process_uid,
only_invalid=only_invalid)
except DatabaseError:
LOG(
'SQLBase',
ERROR,
'%r raised, considering there are no activities' % (
hasMessage,
),
error=True,
)
else:
return result[0].message_count > 0
return 0
def getPriority(self, activity_tool):
result = activity_tool.SQLBase_getPriority(table=self.sql_table)
if result:
result, = result
return result['priority'], result['date']
return Queue.getPriority(self, activity_tool)
def _retryOnLockError(self, method, args=(), kw={}):
while True:
try:
return method(*args, **kw)
except ConflictError:
# Note that this code assumes that a database adapter translates
# a lock error into a conflict error.
LOG('SQLBase', INFO, 'Got a lock error, retrying...')
# Validation private methods
def _validate(self, activity_tool, method_id=None, message_uid=None, path=None, tag=None,
serialization_tag=None):
if isinstance(method_id, str):
method_id = [method_id]
if isinstance(path, str):
path = [path]
if isinstance(tag, str):
tag = [tag]
if method_id or message_uid or path or tag or serialization_tag:
result = activity_tool.SQLBase_validateMessageList(table=self.sql_table,
method_id=method_id,
message_uid=message_uid,
path=path,
tag=tag,
count=False,
serialization_tag=serialization_tag)
message_list = []
for line in result:
m = Message.load(line.message,
line=line,
uid=line.uid,
date=line.date,
processing_node=line.processing_node)
if not hasattr(m, 'order_validation_text'): # BBB
m.order_validation_text = self.getOrderValidationText(m)
message_list.append(m)
return message_list
def _validate_after_method_id(self, activity_tool, message, value):
return self._validate(activity_tool, method_id=value)
def _validate_after_path(self, activity_tool, message, value):
return self._validate(activity_tool, path=value)
def _validate_after_message_uid(self, activity_tool, message, value):
return self._validate(activity_tool, message_uid=value)
def _validate_after_path_and_method_id(self, activity_tool, message, value):
if not (isinstance(value, (tuple, list)) and len(value) == 2):
LOG('CMFActivity', WARNING,
'unable to recognize value for after_path_and_method_id: %r' % (value,))
return []
return self._validate(activity_tool, path=value[0], method_id=value[1])
def _validate_after_tag(self, activity_tool, message, value):
return self._validate(activity_tool, tag=value)
def _validate_after_tag_and_method_id(self, activity_tool, message, value):
# Count number of occurances of tag and method_id
if not (isinstance(value, (tuple, list)) and len(value) == 2):
LOG('CMFActivity', WARNING,
'unable to recognize value for after_tag_and_method_id: %r' % (value,))
return []
return self._validate(activity_tool, tag=value[0], method_id=value[1])
def _validate_serialization_tag(self, activity_tool, message, value):
return self._validate(activity_tool, serialization_tag=value)
def _log(self, severity, summary):
LOG(self.__class__.__name__, severity, summary,
error=severity>INFO and sys.exc_info() or None)
def getReservedMessageList(self, activity_tool, date, processing_node,
limit=None, group_method_id=None):
"""
Get and reserve a list of messages.
limit
Maximum number of messages to fetch.
This number is not garanted to be reached, because of:
- not enough messages being pending execution
- race condition (other nodes reserving the same messages at the same
time)
This number is guaranted not to be exceeded.
If None (or not given) no limit apply.
"""
assert limit
# Do not check already-assigned messages when trying to reserve more
# activities, because in such case we will find one reserved activity.
result = activity_tool.SQLBase_selectReservedMessageList(
table=self.sql_table,
count=limit,
processing_node=processing_node,
group_method_id=group_method_id,
)
limit -= len(result)
if limit:
reservable = activity_tool.SQLBase_getReservableMessageList(
table=self.sql_table,
count=limit,
processing_node=processing_node,
to_date=date,
group_method_id=group_method_id,
)
if reservable:
activity_tool.SQLBase_reserveMessageList(
uid=[x.uid for x in reservable],
table=self.sql_table,
processing_node=processing_node,
)
# DC.ZRDB.Results.Results does not implement concatenation
# Implement an imperfect (but cheap) concatenation. Do not update
# __items__ nor _data_dictionary.
assert result._names == reservable._names, (result._names,
reservable._names)
result._data += reservable._data
return result
def makeMessageListAvailable(self, activity_tool, uid_list):
"""
Put messages back in processing_node=0 .
"""
if len(uid_list):
activity_tool.SQLBase_makeMessageListAvailable(table=self.sql_table,
uid=uid_list)
def getProcessableMessageLoader(self, activity_tool, processing_node):
# do not merge anything
def load(line):
uid = line.uid
m = Message.load(line.message, uid=uid, line=line)
return m, uid, ()
return load
def getProcessableMessageList(self, activity_tool, processing_node):
"""
Always true:
For each reserved message, delete redundant messages when it gets
reserved (definitely lost, but they are expandable since redundant).
- reserve a message
- set reserved message to processing=1 state
- if this message has a group_method_id:
- reserve a bunch of messages
- until the total "cost" of the group goes over 1
- get one message from the reserved bunch (this messages will be
"needed")
- update the total cost
- set "needed" reserved messages to processing=1 state
- unreserve "unneeded" messages
- return still-reserved message list and a group_method_id
If any error happens in above described process, try to unreserve all
messages already reserved in that process.
If it fails, complain loudly that some messages might still be in an
unclean state.
Returned values:
4-tuple:
- list of messages
- group_method_id
- uid_to_duplicate_uid_list_dict
"""
def getReservedMessageList(limit, group_method_id=None):
line_list = self.getReservedMessageList(activity_tool=activity_tool,
date=now_date,
processing_node=processing_node,
limit=limit,
group_method_id=group_method_id)
if line_list:
self._log(TRACE, 'Reserved messages: %r' % [x.uid for x in line_list])
return line_list
now_date = self.getNow(activity_tool)
uid_to_duplicate_uid_list_dict = {}
try:
result = getReservedMessageList(1)
if result:
load = self.getProcessableMessageLoader(activity_tool, processing_node)
m, uid, uid_list = load(result[0])
message_list = [m]
uid_to_duplicate_uid_list_dict[uid] = uid_list
group_method_id = m.line.group_method_id
if group_method_id != '\0':
# Count the number of objects to prevent too many objects.
cost = m.activity_kw.get('group_method_cost', .01)
assert 0 < cost <= 1, (self.sql_table, uid)
count = m.getObjectCount(activity_tool)
# this is heuristic (messages with same group_method_id
# are likely to have the same group_method_cost)
limit = int(1. / cost + 1 - count)
if limit > 1: # <=> cost * count < 1
cost *= count
# Retrieve objects which have the same group method.
result = iter(getReservedMessageList(limit, group_method_id))
for line in result:
if line.uid in uid_to_duplicate_uid_list_dict:
continue
m, uid, uid_list = load(line)
if m is None:
uid_to_duplicate_uid_list_dict[uid] += uid_list
continue
uid_to_duplicate_uid_list_dict[uid] = uid_list
cost += m.getObjectCount(activity_tool) * \
m.activity_kw.get('group_method_cost', .01)
message_list.append(m)
if cost >= 1:
# Unreserve extra messages as soon as possible.
self.makeMessageListAvailable(activity_tool=activity_tool,
uid_list=[line.uid for line in result if line.uid != uid])
activity_tool.SQLBase_processMessage(table=self.sql_table,
uid=uid_to_duplicate_uid_list_dict.keys())
return message_list, group_method_id, uid_to_duplicate_uid_list_dict
except:
self._log(WARNING, 'Exception while reserving messages.')
if uid_to_duplicate_uid_list_dict:
to_free_uid_list = uid_to_duplicate_uid_list_dict.keys()
for uid_list in uid_to_duplicate_uid_list_dict.itervalues():
to_free_uid_list += uid_list
try:
self.makeMessageListAvailable(activity_tool=activity_tool,
uid_list=to_free_uid_list)
except:
self._log(ERROR, 'Failed to free messages: %r' % to_free_uid_list)
else:
if to_free_uid_list:
self._log(TRACE, 'Freed messages %r' % to_free_uid_list)
else:
self._log(TRACE, '(no message was reserved)')
return [], None, uid_to_duplicate_uid_list_dict
def _abort(self):
try:
transaction.abort()
except:
# Unfortunately, database adapters may raise an exception against abort.
self._log(PANIC,
'abort failed, thus some objects may be modified accidentally')
raise
# Queue semantic
def dequeueMessage(self, activity_tool, processing_node):
message_list, group_method_id, uid_to_duplicate_uid_list_dict = \
self.getProcessableMessageList(activity_tool, processing_node)
if message_list:
# Remove group_id parameter from group_method_id
if group_method_id is not None:
group_method_id = group_method_id.split('\0')[0]
if group_method_id not in (None, ""):
method = activity_tool.invokeGroup
args = (group_method_id, message_list, self.__class__.__name__,
hasattr(self, 'generateMessageUID'))
activity_runtime_environment = ActivityRuntimeEnvironment(None)
else:
method = activity_tool.invoke
message = message_list[0]
args = (message, )
activity_runtime_environment = ActivityRuntimeEnvironment(message)
# Commit right before executing messages.
# As MySQL transaction does not start exactly at the same time as ZODB
# transactions but a bit later, messages available might be called
# on objects which are not available - or available in an old
# version - to ZODB connector.
# So all connectors must be committed now that we have selected
# everything needed from MySQL to get a fresh view of ZODB objects.
transaction.commit()
transaction.begin()
# Try to invoke
try:
with activity_runtime_environment:
method(*args)
# Abort if at least 1 message failed. On next tic, only those that
# succeeded will be selected because their at_date won't have been
# increased.
for m in message_list:
if m.getExecutionState() == MESSAGE_NOT_EXECUTED:
raise _DequeueMessageException
transaction.commit()
except:
exc_info = sys.exc_info()
if exc_info[1] is not _DequeueMessageException:
self._log(WARNING,
'Exception raised when invoking messages (uid, path, method_id) %r'
% [(m.uid, m.object_path, m.method_id) for m in message_list])
for m in message_list:
m.setExecutionState(MESSAGE_NOT_EXECUTED, exc_info, log=False)
self._abort()
exc_info = message_list[0].exc_info
if exc_info:
try:
# Register it again.
with activity_runtime_environment:
cancel = message.on_error_callback(*exc_info)
del exc_info, message.exc_info
transaction.commit()
if cancel:
message.setExecutionState(MESSAGE_EXECUTED)
except:
self._log(WARNING, 'Exception raised when processing error callbacks')
message.setExecutionState(MESSAGE_NOT_EXECUTED)
self._abort()
self.finalizeMessageExecution(activity_tool, message_list,
uid_to_duplicate_uid_list_dict)
transaction.commit()
return not message_list
def finalizeMessageExecution(self, activity_tool, message_list,
uid_to_duplicate_uid_list_dict=None):
"""
If everything was fine, delete all messages.
If anything failed, make successful messages available (if any), and
the following rules apply to failed messages:
- Failures due to ConflictErrors cause messages to be postponed,
but their retry count is *not* increased.
- Failures of messages already above maximum retry count cause them to
be put in a permanent-error state.
- In all other cases, retry count is increased and message is delayed.
"""
deletable_uid_list = []
delay_uid_list = []
final_error_uid_list = []
make_available_uid_list = []
notify_user_list = []
executed_uid_list = deletable_uid_list
if uid_to_duplicate_uid_list_dict is not None:
for m in message_list:
if m.getExecutionState() == MESSAGE_NOT_EXECUTED:
executed_uid_list = make_available_uid_list
break
for m in message_list:
uid = m.uid
if m.getExecutionState() == MESSAGE_EXECUTED:
executed_uid_list.append(uid)
if uid_to_duplicate_uid_list_dict is not None:
executed_uid_list += uid_to_duplicate_uid_list_dict.get(uid, ())
elif m.getExecutionState() == MESSAGE_NOT_EXECUTED:
# Should duplicate messages follow strictly the original message, or
# should they be just made available again ?
if uid_to_duplicate_uid_list_dict is not None:
make_available_uid_list += uid_to_duplicate_uid_list_dict.get(uid, ())
if (m.exc_type and # m.exc_type may be None
(m.conflict_retry if issubclass(m.exc_type, ConflictError) else
m.exc_type is SkippedMessage)):
delay_uid_list.append(uid)
else:
max_retry = m.max_retry
retry = m.line.retry
if max_retry is not None and retry >= max_retry:
# Always notify when we stop retrying.
notify_user_list.append((m, False))
final_error_uid_list.append(uid)
continue
# In case of infinite retry, notify the user
# when the default limit is reached.
if max_retry is None and retry == DEFAULT_MAX_RETRY:
notify_user_list.append((m, True))
delay = m.delay
if delay is None:
# By default, make delay quadratic to the number of retries.
delay = VALIDATION_ERROR_DELAY * (retry * retry + 1) * 2
try:
# Immediately update, because values different for every message
activity_tool.SQLBase_reactivate(table=self.sql_table,
uid=[uid],
delay=delay,
retry=1)
except:
self._log(WARNING, 'Failed to reactivate %r' % uid)
make_available_uid_list.append(uid)
else: # MESSAGE_NOT_EXECUTABLE
# 'path' does not point to any object. Activities are normally flushed
# (without invoking them) when an object is deleted, but this is only
# an optimisation. There is no efficient and reliable way to do such
# this, because a concurrent and very long transaction may be about to
# activate this object, without conflict.
# So we have to clean up any remaining activity.
deletable_uid_list.append(uid)
if deletable_uid_list:
try:
self._retryOnLockError(activity_tool.SQLBase_delMessage,
kw={'table': self.sql_table,
'uid': deletable_uid_list})
except:
self._log(ERROR, 'Failed to delete messages %r' % deletable_uid_list)
else:
self._log(TRACE, 'Deleted messages %r' % deletable_uid_list)
if delay_uid_list:
try:
# If this is a conflict error, do not increase 'retry' but only delay.
activity_tool.SQLBase_reactivate(table=self.sql_table,
uid=delay_uid_list, delay=VALIDATION_ERROR_DELAY, retry=None)
except:
self._log(ERROR, 'Failed to delay %r' % delay_uid_list)
if final_error_uid_list:
try:
activity_tool.SQLBase_assignMessage(table=self.sql_table,
uid=final_error_uid_list, processing_node=INVOKE_ERROR_STATE)
except:
self._log(ERROR, 'Failed to set message to error state for %r'
% final_error_uid_list)
if make_available_uid_list:
try:
self.makeMessageListAvailable(activity_tool=activity_tool,
uid_list=make_available_uid_list)
except:
self._log(ERROR, 'Failed to unreserve %r' % make_available_uid_list)
else:
self._log(TRACE, 'Freed messages %r' % make_available_uid_list)
try:
for m, retry in notify_user_list:
m.notifyUser(activity_tool, retry)
except:
# Notification failures must not cause this method to raise.
self._log(WARNING,
'Exception during notification phase of finalizeMessageExecution')
def flush(self, activity_tool, object_path, invoke=0, method_id=None, **kw):
"""
object_path is a tuple
"""
path = '/'.join(object_path)
if invoke:
invoked = set()
def invoke(message):
try:
key = self.generateMessageUID(message)
if key in invoked:
return
invoked.add(key)
except AttributeError:
pass
line = getattr(message, 'line', None)
validate_value = VALID if line and line.processing_node != -1 else \
message.validate(self, activity_tool)
if validate_value == VALID:
# Try to invoke the message - what happens if invoke calls flushActivity ??
with ActivityRuntimeEnvironment(message):
activity_tool.invoke(message)
if message.getExecutionState() != MESSAGE_EXECUTED:
raise ActivityFlushError('Could not invoke %s on %s'
% (message.method_id, path))
elif validate_value is INVALID_PATH:
raise ActivityFlushError('The document %s does not exist' % path)
else:
raise ActivityFlushError('Could not validate %s on %s'
% (message.method_id, path))
for m in activity_tool.getRegisteredMessageList(self):
if object_path == m.object_path and (
method_id is None or method_id == m.method_id):
if invoke:
invoke(m)
activity_tool.unregisterMessage(self, m)
uid_list = []
for line in self._getMessageList(activity_tool, path=path, processing=0,
**({'method_id': method_id} if method_id else {})):
uid_list.append(line.uid)
if invoke:
invoke(Message.load(line.message, uid=line.uid, line=line))
if uid_list:
activity_tool.SQLBase_delMessage(table=self.sql_table, uid=uid_list)
# Required for tests
def timeShift(self, activity_tool, delay, processing_node=None):
"""
To simulate time shift, we simply substract delay from
all dates in message(_queue) table
"""
activity_tool.SQLBase_timeShift(table=self.sql_table, delay=delay,
processing_node=processing_node)