Python Manual Benutzerhandbuch

plicitly close off the session, it would be automatically closed after a period of 60 seconds of inactivity,
or whatever period was defined when the session was initiated. An implementation of the database cur-
sor service for this example might be as follows.

class Cursor(netsvc.Service):

def __init__(self,name,cursor,timeout):

netsvc.Service.__init__(self,name)

self.joinGroup("database-services")

self._cursor = cursor

self._timeout = timeout

self._restart()

self.exportMethod(self.execute)

self.exportMethod(self.executemany)

self.exportMethod(self.description)

self.exportMethod(self.rowcount)

self.exportMethod(self.fetchone)

self.exportMethod(self.fetchmany)

self.exportMethod(self.fetchall)

self.exportMethod(self.arraysize)

self.exportMethod(self.close)

def encodeObject(self,object):

if hasattr(MySQLdb,"DateTime"):

if type(object) == MySQLdb.DateTimeType:

return ("xsd:string",object.strftime())

elif type(object) == MySQLdb.DateTimeDeltaType:

return ("xsd:string",str(object))

return netsvc.Service.encodeObject(self,object)

def executeMethod(self,name,method,params):

try:

return netsvc.Service.executeMethod(self,name,method,params)

except MySQLdb.ProgrammingError,exception:

self.abortResponse(1,"Programming Error","db",str(exception))

except MySQLdb.Error,(error,description):

self.abortResponse(error,description,"mysql")

def _restart(self):

self.cancelTimer("idle")

self.startTimer(self._expire,self._timeout,"idle")

def _expire(self,name):

if name == "idle":

self.close()

def execute(self,query,args=None):

result = self._cursor.execute(query,args)

self._restart()

return result

# additional methods

def close(self):

self._cursor.close()