On Wed, 2 Apr 2008 13:05:49 -0600, Nathan <nathan.stocks@gmail.com> wrote:

On my AMP server I'm using twisted.enterprise to query a postgres database and do inserts. I'd like to return whether the insert succeeded or failed as the response to the AMP responder function -- is there an established pattern for doing things like that?

If a responder returns a Deferred, then the result of the Deferred is taken as the response to the request.

So basically, with the amp command:

class MyInsert(amp.Command): arguments = [('an_int',amp.Integer())] response = [('succeeded',amp.Boolean())]

....on the client I do:

amp_client.callRemote(MyInsert, an_int)

...on the server:

@MyInsert.responder def my_insert(self, an_int): qry_def = self.dbpool.runOperation("insert into mytable the_number values (%d);" % an_int) qry_def.addCallback(self._my_insert_ok) qry_def.addErrback(self._my_insert_err) # Here's the AMP response...but I don't KNOW whether it succeeded yet! # ...but I've _got_ to return a response dict from this function or AMP gives an error! return {'succeeded':True}

Don't return that dict here. Return qry_def, instead. Make your callbacks return dicts or raise exceptions to indicate the result. Jean-Paul