[Twisted-Python] Dealing with an intermittent PB server

[Dave Cook]

I'm rendering the results of a remote method call:

    def data_tableList(self, ctx, data):
        ...
        d =   self.pbClientFactory.login(creds)
        d.addCallback(lambda object: object.callRemote("foo"))
        return d
 
Works, great if the PB server is up,  but if it's down the browser
just hangs.  Is there a correct way to check that the connection is up
at this point?  This works:

       if self.pbClientFactory._broker:
            d = self.pbClientFactory.login(creds)
            d.addCallback(lambda object: object.callRemote("getAlertReports"))
        else:
            d = []
        return d

but seems like a hack.  Also, ideally, I'd like to attempt a
reconnection to the PB server at this point if it's not running. 
What's the best way to do that?

Thanks,
Dave Cook