def runInteraction(self, interaction, *args, **kw):
"""
Interact with the database and return the result.
The 'interaction' is a callable object which will be executed
in a thread using a pooled connection. It will be passed an
L{Transaction} object as an argument (whose interface is
identical to that of the database cursor for your DB-API
module of choice), and its results will be returned as a
Deferred. If running the method raises an exception, the
transaction will be rolled back. If the method returns a
value, the transaction will be committed.
NOTE that the function you pass is *not* run in the main
thread: you may have to worry about thread-safety in the
function you pass to this if it tries to use non-local
objects.
@param interaction: a callable object whose first argument
is an L{adbapi.Transaction}.
@param *args: additional positional arguments to be passed
to interaction
@param **kw: keyword arguments to be passed to interaction
@return: a Deferred which will fire the return value of
'interaction(Transaction(...), *args, **kw)', or a Failure.
"""
from lib.twisted.internet import reactor
return threads.deferToThreadPool(reactor, self.threadpool,
self._runInteraction,
interaction, *args, **kw)
def runWithConnection(self, func, *args, **kw):
"""
Execute a function with a database connection and return the result.
@param func: A callable object of one argument which will be executed
in a thread with a connection from the pool. It will be passed as
its first argument a L{Connection} instance (whose interface is
mostly identical to that of a connection object for your DB-API
module of choice), and its results will be returned as a Deferred.
If the method raises an exception the transaction will be rolled
back. Otherwise, the transaction will be committed. B{Note} that
this function is B{not} run in the main thread: it must be
threadsafe.
@param *args: positional arguments to be passed to func
@param **kw: keyword arguments to be passed to func
@return: a Deferred which will fire the return value of
C{func(Transaction(...), *args, **kw)}, or a Failure.
"""
from lib.twisted.internet import reactor
return threads.deferToThreadPool(reactor, self.threadpool,
self._runWithConnection,
func, *args, **kw)
def runInteraction(self, interaction, *args, **kw):
"""
Interact with the database and return the result.
The 'interaction' is a callable object which will be executed
in a thread using a pooled connection. It will be passed an
L{Transaction} object as an argument (whose interface is
identical to that of the database cursor for your DB-API
module of choice), and its results will be returned as a
Deferred. If running the method raises an exception, the
transaction will be rolled back. If the method returns a
value, the transaction will be committed.
NOTE that the function you pass is *not* run in the main
thread: you may have to worry about thread-safety in the
function you pass to this if it tries to use non-local
objects.
@param interaction: a callable object whose first argument
is an L{adbapi.Transaction}.
@param *args: additional positional arguments to be passed
to interaction
@param **kw: keyword arguments to be passed to interaction
@return: a Deferred which will fire the return value of
'interaction(Transaction(...), *args, **kw)', or a Failure.
"""
from lib.twisted.internet import reactor
return threads.deferToThreadPool(reactor, self.threadpool,
self._runInteraction, interaction,
*args, **kw)
def runWithConnection(self, func, *args, **kw):
"""
Execute a function with a database connection and return the result.
@param func: A callable object of one argument which will be executed
in a thread with a connection from the pool. It will be passed as
its first argument a L{Connection} instance (whose interface is
mostly identical to that of a connection object for your DB-API
module of choice), and its results will be returned as a Deferred.
If the method raises an exception the transaction will be rolled
back. Otherwise, the transaction will be committed. B{Note} that
this function is B{not} run in the main thread: it must be
threadsafe.
@param *args: positional arguments to be passed to func
@param **kw: keyword arguments to be passed to func
@return: a Deferred which will fire the return value of
C{func(Transaction(...), *args, **kw)}, or a Failure.
"""
from lib.twisted.internet import reactor
return threads.deferToThreadPool(reactor, self.threadpool,
self._runWithConnection, func, *args,
**kw)
def getHostByName(self, name, timeout=(1, 3, 11, 45)):
"""
See L{lib.twisted.internet.interfaces.IResolverSimple.getHostByName}.
Note that the elements of C{timeout} are summed and the result is used
as a timeout for the lookup. Any intermediate timeout or retry logic
is left up to the platform via L{socket.gethostbyname}.
"""
if timeout:
timeoutDelay = sum(timeout)
else:
timeoutDelay = 60
userDeferred = defer.Deferred()
lookupDeferred = threads.deferToThreadPool(
self.reactor, self.reactor.getThreadPool(), socket.gethostbyname, name
)
cancelCall = self.reactor.callLater(timeoutDelay, self._cleanup, name, lookupDeferred)
self._runningQueries[lookupDeferred] = (userDeferred, cancelCall)
lookupDeferred.addBoth(self._checkTimeout, name, lookupDeferred)
return userDeferred
def getHostByName(self, name, timeout = (1, 3, 11, 45)):
"""
See L{lib.twisted.internet.interfaces.IResolverSimple.getHostByName}.
Note that the elements of C{timeout} are summed and the result is used
as a timeout for the lookup. Any intermediate timeout or retry logic
is left up to the platform via L{socket.gethostbyname}.
"""
if timeout:
timeoutDelay = sum(timeout)
else:
timeoutDelay = 60
userDeferred = defer.Deferred()
lookupDeferred = threads.deferToThreadPool(
self.reactor, self.reactor.getThreadPool(),
socket.gethostbyname, name)
cancelCall = self.reactor.callLater(
timeoutDelay, self._cleanup, name, lookupDeferred)
self._runningQueries[lookupDeferred] = (userDeferred, cancelCall)
lookupDeferred.addBoth(self._checkTimeout, name, lookupDeferred)
return userDeferred
