/usr/share/doc/pyro4/examples/disconnects/client.py is in pyro4-examples 4.23-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | from __future__ import print_function
import sys
import Pyro4
import Pyro4.message
import warnings
warnings.filterwarnings("ignore")
if sys.version_info < (3, 0):
input = raw_input
print("You can run this client on a different computer so you can disable the network connection (by yanking out the lan cable or whatever).")
print("Alternatively, wait for a timeout on the server, which will then close its connection.")
uri = input("Uri of server? ").strip()
class AutoReconnectingProxy(Pyro4.core.Proxy):
"""
A Pyro proxy that automatically recovers from a server disconnect.
It does this by intercepting every method call and then it first 'pings'
the server to see if it still has a working connection. If not, it
reconnects the proxy and retries the method call.
Drawback is that every method call now uses two remote messages (a ping,
and the actual method call).
This uses some advanced features of the Pyro API.
"""
def _pyroInvoke(self, methodname, vargs, kwargs, flags=0):
# first test if we have an open connection, if not, we just reconnect
if self._pyroConnection:
try:
print(" <proxy: ping>")
# send the special 'ping' message to the daemon, to see if this connection is still alive
# we expect a 'ping' response (no-op)
ping = Pyro4.message.Message(Pyro4.message.MSG_PING, b"", 42, 0, 0)
self._pyroConnection.send(ping.to_bytes())
Pyro4.message.Message.recv(self._pyroConnection, [Pyro4.message.MSG_PING])
print(" <proxy: ping reply (still connected)>")
except Pyro4.errors.ConnectionClosedError: # or possibly even ProtocolError
print(" <proxy: Connection lost. REBINDING...>")
self._pyroReconnect()
print(" <proxy: Connection restored, continue with actual method call...>")
return super(AutoReconnectingProxy, self)._pyroInvoke(methodname, vargs, kwargs, flags)
with AutoReconnectingProxy(uri) as obj:
result = obj.echo("12345")
print("result =", result)
print("\nClient proxy connection is still open. Disable the network now (or wait until the connection timeout on the server expires) and see what the server does.")
print("Once you see on the server that it got a timeout or a disconnect, enable the network again.")
input("Press enter to continue:")
print("\nDoing a new call on the same proxy:")
result = obj.echo("12345")
print("result =", result)
|