[Twisted-Python] Bring multi service up gradually
fairwinds at eastlink.ca
Fri Jun 16 09:39:56 EDT 2006
> I don't think there is a way to insure you will get the ports you want.
> Why bother testing if the port is available before hand? In between the
> port being tested and the application using it someone can sneak in and
> take it.
Hi Chaz. Thank you for your reply. The reason for the test is that I
don't want the other services to start at all if a connection cannot be
found to run the main service. I was thinking of writing a simple tester
using socket module to determine which addresses are alive first. When
it finds one it stops so in my logic I give this address to my
ListenTCP/SSL and attempt to start the main service.
I don't expect the address list to be large. This way no time is lost
with the client running through a long backoff cycle on an address that
may not be alive only to have to stop it and try a another until one is
I am not aware of something in twisted that evaluates addresses like
this as part of a startup solution. In any case, if I see that an
address in the list is available, then I would start my main service
using it. When a connection is made to the main address, then I want to
start the remaining services since they are useless without the main
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