added close() to servers

[ritksm]

so we can manually close/stop server

[wooparadog]

or you could try using gunicorn_thrift to run your thrift server. And closing server should be as simple as sending the master process a SIGTERM

[ritksm]

@wooparadog I tested my code with gunicorn_thrift, it works fine.

However, I think that thriftpy server should come with a way to stop server after cleanup, instead of introducing some gunicorn features that I don't need.

[lxyu]

when could the close() method be called as the serve() already blocked the main process?

[ritksm]

@lxyu
My case is, when thrift server is going to shutdown, I have to do some cleanup, close some sockets blahblah. So I use signal to handle system signal like SIGQUIT, so there will be a signal handler function where I do clean up.
However, due to server.serve() only respond to KeyboardInterrupt, so I have to raise a KeyboardInterrupt in order to shutdown the thrift server, that seems extremely inappropriate and weird, so a better solution would be providing a close() function to shutdown the server.

[miphip]

The current implementation (0.3.0) doesn't work.

TSimpleServer will only look at self.closed when processor.process returns, i.e. after processing some packets. Then it will get caught in trans.accept() waiting for new client session.

TThreadedServer will only look at self.closed once a client session ends. It can't be stopped if it doesn't gave or get any client sessions since it is stuck in trans.accept() waiting for a client session.

To support stopping the server, a socket timeout must be set causing "socket.accept" and "processor.process" to return regularly to check is self.closed has been set.