def release(self): """ Releases the lock previously locked by a call to acquire(). Returns None. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("releasing exclusive") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if thrCurrent is not self.thrOwner: raise Exception("Current thread has not acquired the lock") # the thread releases its exclusive lock self.intOwnerDepth -= 1 if self.intOwnerDepth > 0: if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("released exclusive") return self.thrOwner = None # a decision is made which pending thread(s) to awake (if any) self._release_threads() if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("released exclusive") finally: self._unlock()
def release_shared(self): """ Releases the lock previously locked by a call to acquire_shared(). Returns None. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("releasing shared") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if thrCurrent not in self.dicUsers: raise Exception("Current thread has not acquired the lock") # the thread releases its shared lock self.dicUsers[thrCurrent] -= 1 if self.dicUsers[thrCurrent] > 0: if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("released shared") return else: del self.dicUsers[thrCurrent] # a decision is made which pending thread(s) to awake (if any) self._release_threads() if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("released shared") finally: self._unlock()
def _execute_sql(self, sql, params): try: param_list = ", ".join("@{0:s} = {1:s}".format(n, v) for n, v in params.items()) at_params = { n: "@{0:s}".format(n) for n in params.keys() } sql = sql.format(**at_params) except: ResourceError.rethrow(recoverable = True, terminal = False) cursor = self._connection.cursor() try: for n, v in params.items(): cursor.execute("SET @{0:s}={1:s}".format(n, v)) pmnc.log.info(">> {0:s}".format(sql)) if param_list: if pmnc.log.debug: pmnc.log.debug("-- {0:s} -- ({1:s})".format(sql, param_list)) records = [] try: cursor.execute(sql) rowcount = cursor.rowcount if rowcount >= 0: pmnc.log.info("<< OK, {0:d} record(s)".format(rowcount)) if rowcount > 0 and cursor.description: column_names = [ t[0] for t in cursor.description ] for record in cursor.fetchall(): records.append(dict(zip(column_names, record))) else: pmnc.log.info("<< OK") except MySQL_Error as e: code, message = e.args[0].args pmnc.log.warning("<< {0:s}{1:s} !! MySQL_Error(\"[{2:d}] {3:s}\") in {4:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", code, message, trace_string())) SQLResourceError.rethrow(recoverable = True, code = code, description = message) # note that there is no state except Exception: pmnc.log.warning("<< {0:s}{1:s} !! {2:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", exc_string())) ResourceError.rethrow(recoverable = True) else: return records finally: cursor.close()
def _execute_sql(self, sql, params): try: sql, params = self._convert_to_qmarks(sql, params) param_list = ", ".join(map(lambda x: isinstance(x, str) and "'{0:s}'".format(x) or str(x), params)) except: ResourceError.rethrow(recoverable = True, terminal = False) pmnc.log.info(">> {0:s}".format(sql)) if param_list: if pmnc.log.debug: pmnc.log.debug("-- {0:s} -- ({1:s})".format(sql, param_list)) records = [] try: self._cursor.execute(sql, params) rowcount = self._cursor.rowcount if rowcount >= 0: pmnc.log.info("<< OK, {0:d} record(s)".format(rowcount)) if self._cursor.description and rowcount > 0: column_names = [ t[0].decode("ascii") for t in self._cursor.description ] for record in self._cursor.fetchall(): records.append(dict(zip(column_names, record))) else: pmnc.log.info("<< OK") except ProgrammingError as e: try: level, state, message = map(self._decode_message, e.args) except: state, message = "PG800", str(e) state = state.upper() pmnc.log.warning("<< {0:s}{1:s} !! PostgreSQL_Error(\"[{2:s}] {3:s}\") in {4:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", state, message, trace_string())) SQLResourceError.rethrow( state = state, description = message, # note that there is no code recoverable = True, terminal = state[:2] not in self._safe_states) except: pmnc.log.warning("<< {0:s}{1:s} !! {2:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", exc_string())) ResourceError.rethrow(recoverable = True) else: return records
def _execute_sql(self, sql, params): try: sql, params = self._convert_bind_points(sql, params) param_list = ", ".join("{0:s}={1:s}".format(k, isinstance(v, str) and "'{0:s}'".format(v) or str(v)) for k, v in params.items()) except: ResourceError.rethrow(recoverable = True, terminal = False) pmnc.log.info(">> {0:s}".format(sql)) if param_list: if pmnc.log.debug: pmnc.log.debug("-- {0:s} -- ({1:s})".format(sql, param_list)) records = [] try: self._cursor.execute(sql, params) rowcount = self._cursor.rowcount if rowcount >= 0: pmnc.log.info("<< OK, {0:d} record(s)".format(rowcount)) if self._cursor.description and rowcount > 0: column_names = [ t.name for t in self._cursor.description ] for record in self._cursor.fetchall(): records.append(dict(zip(column_names, record))) else: pmnc.log.info("<< OK") except PGError as e: state, message = e.pgcode, " ".join(s.strip() for s in e.pgerror.split("\n")) pmnc.log.warning("<< {0:s}{1:s} !! {2:s}(\"{3:s}{4:s}\") in {5:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", e.__class__.__name__, "[{0:s}] ".format(state) if state else "", message, trace_string())) SQLResourceError.rethrow( state = state, description = message, # note that there is no code recoverable = True, terminal = not state or state[:2] not in self._safe_states) except: pmnc.log.warning("<< {0:s}{1:s} !! {2:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", exc_string())) ResourceError.rethrow(recoverable = True) else: return records
def _log(self, s): self.__log("{0:s} {1:s} in {2:s}".format( s, self._dump(), exc_string.trace_string(skip=1)))
def _log(self, s): self.__log("{0:s} {1:s} in {2:s}".format(s, self._dump(), exc_string.trace_string(skip = 1)))
def _execute_sql(self, sql, params): try: sql, params = self._convert_to_named(sql, params) param_list = ", ".join(map(lambda n_v: "{0:s} = {1:s}".\ format(n_v[0], isinstance(n_v[1], str) and "'{0:s}'".format(n_v[1]) or str(n_v[1])), params.items())) except: ResourceError.rethrow(recoverable = True, terminal = False) pmnc.log.info(">> {0:s}".format(sql)) if param_list: if pmnc.log.debug: pmnc.log.debug("-- {0:s} -- ({1:s})".format(sql, param_list)) try: cursor = self._connection.cursor() try: # avoid using floats with numbers cursor.numbersAsStrings = True # avoid truncation of timestamps and intervals param_sizes = {} for n, v in params.items(): if isinstance(v, datetime): param_sizes[n] = TIMESTAMP elif isinstance(v, timedelta): param_sizes[n] = INTERVAL if param_sizes: cursor.setinputsizes(**param_sizes) # execute the query, making stored procedure a special case execute = self._execute_parser.match(sql) if execute: proc_name = execute.group(1) result = self._connection.cursor() try: params.update(result = result) # providing out sys_refcursor parameter result cursor.callproc(proc_name, keywordParameters = params) finally: try: cursor.close() finally: cursor = result else: cursor.execute(sql, **params) # extract the result if cursor.description is not None: description = tuple(dict(name = t[0], type_name = t[1].__name__) for t in cursor.description) records = [ { field["name"]: self.cx_TYPE(field["type_name"], value) for field, value in zip(description, record) } for record in cursor ] else: records = [] # not a SELECT query records_affected = cursor.rowcount finally: cursor.close() if records_affected > 0: pmnc.log.info("<< OK, {0:d} record(s)".format(records_affected)) else: pmnc.log.info("<< OK") except Oracle_Error as e: e = e.args[0] if isinstance(e, _Oracle_Error): code, message = e.code, e.message else: code, message = -1, "cx_Oracle error: {0:s}".format(str(e)) pmnc.log.warning("<< {0:s}{1:s} !! Oracle_Error(\"{2:d}: {3:s}\") in {4:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", code, message, trace_string())) SQLResourceError.rethrow( code = code, description = message, recoverable = True) # note that there is no state except: pmnc.log.warning("<< {0:s}{1:s} !! {2:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", exc_string())) ResourceError.rethrow(recoverable = True) else: return records
def _log(self, s): thrCurrent = currentThread() self.__log("%s @ %.08x %s %s @ %.08x in %s" % (thrCurrent.getName(), id(thrCurrent), s, self._debug_dump(), id(self), trace_string()))
def acquire_shared(self, timeout = None): """ Attempts to acquire the lock in shared mode within the optional timeout. If the timeout is not specified, waits for the lock infinitely. Returns True if the lock has been acquired, False otherwise. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("acquiring shared") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) # this thread already has shared lock, the count is incremented if thrCurrent in self.dicUsers: self.dicUsers[thrCurrent] += 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # this thread already has exclusive lock, now it also has shared elif thrCurrent is self.thrOwner: if thrCurrent in self.dicUsers: self.dicUsers[thrCurrent] += 1 else: self.dicUsers[thrCurrent] = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # a thread acquires shared lock whenever there is no owner # nor pending owners (to prevent owners starvation) elif not self._has_owner() and not self._has_pending_owners(): self.dicUsers[thrCurrent] = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # otherwise the thread registers itself as a pending user else: evtEvent = self._pick_event() self.lstUsers.append((thrCurrent, evtEvent, 1)) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("waiting for shared") finally: self._unlock() return self._acquire_event(evtEvent, timeout) # the thread waits for a lock release
def acquire(self, timeout = None): """ Attempts to acquire the lock exclusively within the optional timeout. If the timeout is not specified, waits for the lock infinitely. Returns True if the lock has been acquired, False otherwise. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("acquiring exclusive") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) # this thread already has exclusive lock, the count is incremented if thrCurrent is self.thrOwner: self.intOwnerDepth += 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # this thread already has shared lock, this is the most complicated case elif thrCurrent in self.dicUsers: # the thread gets exclusive lock immediately if there is no other threads if self.dicUsers.keys() == [thrCurrent] \ and not self._has_pending_users() and not self._has_pending_owners(): self.thrOwner = thrCurrent self.intOwnerDepth = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # the thread releases its shared lock in hope for the future # exclusive one intSharedDepth = self.dicUsers.pop(thrCurrent) # that many times it had shared lock evtEvent = self._pick_event() self.lstOwners.append((thrCurrent, evtEvent, intSharedDepth)) # it will be given them back self._release_threads() # a thread acquires exclusive lock whenever there is no # current owner nor running users elif not self._has_owner() and not self._has_users(): self.thrOwner = thrCurrent self.intOwnerDepth = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # otherwise the thread registers itself as a pending owner with no # prior record of holding shared lock else: evtEvent = self._pick_event() self.lstOwners.append((thrCurrent, evtEvent, 0)) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("waiting for exclusive") finally: self._unlock() return self._acquire_event(evtEvent, timeout) # the thread waits for a lock release
def _acquire_event(self, _evtEvent, timeout): # puts the thread to sleep until the # lock is acquired or timeout elapses if timeout is None: _evtEvent.wait() result = True else: _evtEvent.wait(timeout) result = _evtEvent.isSet() thrCurrent = currentThread() self._lock() try: # even if result indicates failure, the thread might still be having # the lock (race condition between the isSet() and _lock() above) if not result: result = _evtEvent.isSet() # if the lock has not been acquired, the thread must be removed from # the pending list it's on. in case the thread was waiting for the # exclusive lock and it previously had shared locks, it's put to sleep # again this time infinitely (!), waiting for its shared locks back boolReAcquireShared = False if not result: # the thread has failed to acquire the lock for i, (thrUser, evtEvent, intSharedDepth) in enumerate(self.lstUsers): if thrUser is thrCurrent and evtEvent is _evtEvent: assert intSharedDepth == 1 del self.lstUsers[i] break else: for i, (thrOwner, evtEvent, intSharedDepth) in enumerate(self.lstOwners): if thrOwner is thrCurrent and evtEvent is _evtEvent: del self.lstOwners[i] if intSharedDepth > 0: if not self._has_owner(): self.dicUsers[thrCurrent] = intSharedDepth else: self.lstUsers.append((thrCurrent, _evtEvent, intSharedDepth)) boolReAcquireShared = True break else: assert False, "Invalid thread for %s in %s" % \ (self._debug_dump(), trace_string()) # if a thread has failed to acquire a lock, it's identical as if it had # it and then released, therefore other threads should be released now self._release_threads() if not boolReAcquireShared: _evtEvent.clear() self._unpick_event(_evtEvent) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if result: if self.__log: self._log("acquired") else: if self.__log: self._log("timed out in %.02f second(s) waiting for" % timeout) if boolReAcquireShared: if self.__log: self._log("acquiring %d previously owned shared lock(s) for" % intSharedDepth) finally: self._unlock() if boolReAcquireShared: assert self._acquire_event(_evtEvent, None) return False return result
def _acquire_event(self, _evtEvent, timeout): # puts the thread to sleep until the # lock is acquired or timeout elapses if timeout is None: _evtEvent.wait() result = True else: _evtEvent.wait(timeout) result = _evtEvent.isSet() thrCurrent = currentThread() self._lock() try: # even if result indicates failure, the thread might still be having # the lock (race condition between the isSet() and _lock() above) if not result: result = _evtEvent.isSet() # if the lock has not been acquired, the thread must be removed from # the pending list it's on. in case the thread was waiting for the # exclusive lock and it previously had shared locks, it's put to sleep # again this time infinitely (!), waiting for its shared locks back boolReAcquireShared = False if not result: # the thread has failed to acquire the lock for i, (thrUser, evtEvent, intSharedDepth) in enumerate(self.lstUsers): if thrUser is thrCurrent and evtEvent is _evtEvent: assert intSharedDepth == 1 del self.lstUsers[i] break else: for i, (thrOwner, evtEvent, intSharedDepth) in enumerate(self.lstOwners): if thrOwner is thrCurrent and evtEvent is _evtEvent: del self.lstOwners[i] if intSharedDepth > 0: if not self._has_owner(): self.dicUsers[thrCurrent] = intSharedDepth else: self.lstUsers.append( (thrCurrent, _evtEvent, intSharedDepth)) boolReAcquireShared = True break else: assert False, "Invalid thread for %s in %s" % \ (self._debug_dump(), trace_string()) # if a thread has failed to acquire a lock, it's identical as if it had # it and then released, therefore other threads should be released now self._release_threads() if not boolReAcquireShared: _evtEvent.clear() self._unpick_event(_evtEvent) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if result: if self.__log: self._log("acquired") else: if self.__log: self._log("timed out in %.02f second(s) waiting for" % timeout) if boolReAcquireShared: if self.__log: self._log( "acquiring %d previously owned shared lock(s) for" % intSharedDepth) finally: self._unlock() if boolReAcquireShared: assert self._acquire_event(_evtEvent, None) return False return result
def acquire(self, timeout=None): """ Attempts to acquire the lock exclusively within the optional timeout. If the timeout is not specified, waits for the lock infinitely. Returns True if the lock has been acquired, False otherwise. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("acquiring exclusive") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) # this thread already has exclusive lock, the count is incremented if thrCurrent is self.thrOwner: self.intOwnerDepth += 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # this thread already has shared lock, this is the most complicated case elif thrCurrent in self.dicUsers: # the thread gets exclusive lock immediately if there is no other threads if self.dicUsers.keys() == [thrCurrent] \ and not self._has_pending_users() and not self._has_pending_owners(): self.thrOwner = thrCurrent self.intOwnerDepth = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # the thread releases its shared lock in hope for the future # exclusive one intSharedDepth = self.dicUsers.pop( thrCurrent) # that many times it had shared lock evtEvent = self._pick_event() self.lstOwners.append( (thrCurrent, evtEvent, intSharedDepth)) # it will be given them back self._release_threads() # a thread acquires exclusive lock whenever there is no # current owner nor running users elif not self._has_owner() and not self._has_users(): self.thrOwner = thrCurrent self.intOwnerDepth = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired exclusive") return True # otherwise the thread registers itself as a pending owner with no # prior record of holding shared lock else: evtEvent = self._pick_event() self.lstOwners.append((thrCurrent, evtEvent, 0)) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("waiting for exclusive") finally: self._unlock() return self._acquire_event( evtEvent, timeout) # the thread waits for a lock release
def acquire_shared(self, timeout=None): """ Attempts to acquire the lock in shared mode within the optional timeout. If the timeout is not specified, waits for the lock infinitely. Returns True if the lock has been acquired, False otherwise. """ thrCurrent = currentThread() self._lock() try: if self.__log: self._log("acquiring shared") if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) # this thread already has shared lock, the count is incremented if thrCurrent in self.dicUsers: self.dicUsers[thrCurrent] += 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # this thread already has exclusive lock, now it also has shared elif thrCurrent is self.thrOwner: if thrCurrent in self.dicUsers: self.dicUsers[thrCurrent] += 1 else: self.dicUsers[thrCurrent] = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # a thread acquires shared lock whenever there is no owner # nor pending owners (to prevent owners starvation) elif not self._has_owner() and not self._has_pending_owners(): self.dicUsers[thrCurrent] = 1 if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("acquired shared") return True # otherwise the thread registers itself as a pending user else: evtEvent = self._pick_event() self.lstUsers.append((thrCurrent, evtEvent, 1)) if self.__debug: assert self._invariant(), "SharedLock invariant failed: %s in %s" % \ (self._debug_dump(), trace_string()) if self.__log: self._log("waiting for shared") finally: self._unlock() return self._acquire_event( evtEvent, timeout) # the thread waits for a lock release
def _execute_sql(self, sql, params): try: sql, params = self._convert_to_qmarks(sql, params) param_list = ", ".join(map(lambda t_s_v: "{0:s}({1:s})".\ format(t_s_v[0], isinstance(t_s_v[2], str) and "'{0:s}'".format(t_s_v[2]) or str(t_s_v[2])), params)) except: ResourceError.rethrow(recoverable = True, terminal = False) pmnc.log.info(">> {0:s}".format(sql)) if param_list: if pmnc.log.debug: pmnc.log.debug("-- {0:s} -- ({1:s})".format(sql, param_list)) records = [] try: command = com_client.Dispatch("ADODB.Command") command.CommandText = sql command.CommandType = 1 # adCmdText for i, (param_type, param_size, param_value) in enumerate(params): param = command.CreateParameter(None, ADODataTypes[param_type], 1, # adParamInput param_size, param_value) if param_type in ("adDecimal", "adNumeric"): param.Precision = self.precision param.NumericScale = self.scale command.Parameters.Append(param) command.ActiveConnection = self._connection command.Prepared = True recordset = command.Execute()[0] if recordset.State == 1: # adStateOpen try: while not recordset.EOF: records.append({ field.Name: TypeValueWrapper((field.Type, field.Value)) for field in recordset.Fields }) recordset.MoveNext() finally: recordset.Close() pmnc.log.info("<< OK, {0:d} record(s)".format(len(records))) else: pmnc.log.info("<< OK") except com_error: tb, code, state, description = self._extract_adodb_error() state_brace = " [{0:s}]".format(state) if state is not None else "" pmnc.log.warning("<< {0:s}{1:s} !! ADODB_Error(\"{2:d}:{3:s} {4:s}\") in {5:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", code, state_brace, description, trace_string())) SQLResourceError.rethrow( code = code, state = state, description = description, recoverable = True, terminal = state[:2] not in self._safe_states) except: pmnc.log.warning("<< {0:s}{1:s} !! {2:s}".\ format(sql, " -- ({0:s})".format(param_list) if param_list else "", exc_string())) ResourceError.rethrow(recoverable = True) else: return records