[Twisted-Python] pending twisted fixes

[Glyph Lefkowitz]

Andrea Arcangeli wrote:

> These are the pending fixes for twisted that I'm maintaining on my tree.

Thanks for reporting these, especially the fix backports.  I guess 
Twisted is a big enough project now that we need to start doing 
maintenance release trees!

> The transport.disconnecting was said not to be available for all
> twisted transports, but then it should be added to the others instead of
> my rejecting my patch with that argument (those basic.py protocols are
> broken without this fix, so it's better that they fail with a visible
> exception than subtly at runtime), or another method should be
> implemented to know if the transport has disconnected already.

Hmm.  True enough.

I've seen this problem before but not thought too hard about it. 
Considering it now, I think the right solution is to add a 
'disconnecting' attribute to ITransport, and fix all current Twisted 
ITransport implementations to include it.  I know that this is about to 
become an issue for me with Q2Q.

(Also, should we maybe have a distinction between IStreamTransport and 
IDatagramTransport, rather than just ITCPTransport/IUDPTransport?  or at 
least some attributes to introspect, like ".reliable" and ".ordered"?)