bootstrap-vz/bootstrapvz/base/remote/ssh_rpc_manager.py
2015-04-16 22:15:19 +02:00

72 lines
2.3 KiB
Python

import logging
log = logging.getLogger(__name__)
class SSHRPCManager(object):
def __init__(self, settings):
self.settings = settings
# We can't use :0 because
# A: It's quite hard to retrieve the port on the remote after the daemon has started
# B: SSH doesn't accept 0:localhost:0 as a port forwarding option
[self.local_server_port, self.local_callback_port] = self.getNPorts(2)
[self.remote_server_port, self.remote_callback_port] = self.getNPorts(2)
def getNPorts(self, n, port_range=(1024, 65535)):
import random
ports = []
for i in range(0, n):
while True:
port = random.randrange(*port_range)
if port not in ports:
ports.append(port)
break
return ports
def start(self):
log.debug('Opening SSH connection')
import subprocess
ssh_cmd = ['ssh', '-i', self.settings['keyfile'],
'-p', str(self.settings['port']),
'-L' + str(self.local_server_port) + ':localhost:' + str(self.remote_server_port),
'-R' + str(self.remote_callback_port) + ':localhost:' + str(self.local_callback_port),
self.settings['username'] + '@' + self.settings['address'],
'--',
'sudo', self.settings['server_bin'],
'--listen', str(self.remote_server_port)]
import sys
self.ssh_process = subprocess.Popen(args=ssh_cmd, stdout=sys.stderr, stderr=sys.stderr)
# Check that we can connect to the server
try:
import Pyro4
server_uri = 'PYRO:server@localhost:{server_port}'.format(server_port=self.local_server_port)
self.rpc_server = Pyro4.Proxy(server_uri)
log.debug('Connecting to the RPC daemon')
remaining_retries = 5
while True:
try:
self.rpc_server.ping()
break
except (Pyro4.errors.ConnectionClosedError, Pyro4.errors.CommunicationError) as e:
if remaining_retries > 0:
remaining_retries -= 1
from time import sleep
sleep(2)
else:
raise e
except (Exception, KeyboardInterrupt) as e:
self.ssh_process.terminate()
raise e
def stop(self):
if hasattr(self, 'rpc_server'):
log.debug('Stopping the RPC daemon')
self.rpc_server.stop()
self.rpc_server._pyroRelease()
if hasattr(self, 'ssh_process'):
log.debug('Waiting for the SSH connection to terminate')
self.ssh_process.wait()