bootstrap-vz/bootstrapvz/remote/build_servers/remote.py
2018-02-25 04:12:24 +00:00

130 lines
5.3 KiB
Python

from .build_server import BuildServer
from bootstrapvz.common.tools import log_check_call
from contextlib import contextmanager
import logging
log = logging.getLogger(__name__)
class RemoteBuildServer(BuildServer):
def __init__(self, name, settings):
super(RemoteBuildServer, self).__init__(name, settings)
self.address = settings['address']
self.port = settings['port']
self.username = settings['username']
self.password = settings.get('password', None)
self.keyfile = settings['keyfile']
self.server_bin = settings['server_bin']
@contextmanager
def connect(self):
with self.spawn_server() as forwards:
args = {'listen_port': forwards['local_callback_port'],
'remote_port': forwards['remote_callback_port']}
from .callback import CallbackServer
with CallbackServer(**args) as callback_server:
with connect_pyro('localhost', forwards['local_server_port']) as connection:
connection.set_callback_server(callback_server)
yield connection
@contextmanager
def spawn_server(self):
from . import getNPorts
# We can't use :0 for the forwarding ports 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
[local_server_port, local_callback_port] = getNPorts(2)
[remote_server_port, remote_callback_port] = getNPorts(2)
server_cmd = ['sudo', self.server_bin, '--listen', str(remote_server_port)]
def set_process_group():
# Changes the process group of a command so that any SIGINT
# for the main thread will not be propagated to it.
# We'd like to handle SIGINT ourselves (i.e. propagate the shutdown to the serverside)
import os
os.setpgrp()
addr_arg = '{user}@{host}'.format(user=self.username, host=self.address)
ssh_cmd = ['ssh', '-i', self.keyfile,
'-p', str(self.port),
'-L' + str(local_server_port) + ':localhost:' + str(remote_server_port),
'-R' + str(remote_callback_port) + ':localhost:' + str(local_callback_port),
addr_arg]
full_cmd = ssh_cmd + ['--'] + server_cmd
log.debug('Opening SSH connection to build server `{name}\''.format(name=self.name))
import sys
import subprocess
ssh_process = subprocess.Popen(args=full_cmd, stdout=sys.stderr, stderr=sys.stderr,
preexec_fn=set_process_group)
try:
yield {'local_server_port': local_server_port,
'local_callback_port': local_callback_port,
'remote_server_port': remote_server_port,
'remote_callback_port': remote_callback_port}
finally:
log.debug('Waiting for SSH connection to the build server to close')
import time
start = time.time()
while ssh_process.poll() is None:
if time.time() - start > 5:
log.debug('Forcefully terminating SSH connection to the build server')
ssh_process.terminate()
break
else:
time.sleep(0.5)
def download(self, src, dst):
log.debug('Downloading file `{src}\' from '
'build server `{name}\' to `{dst}\''
.format(src=src, dst=dst, name=self.name))
# Make sure we can read the file as {user}
self.remote_command(['sudo', 'chown', self.username, src])
src_arg = '{user}@{host}:{path}'.format(user=self.username, host=self.address, path=src)
log_check_call(['scp', '-i', self.keyfile, '-P', str(self.port),
src_arg, dst])
def delete(self, path):
log.debug('Deleting file `{path}\' on build server `{name}\''.format(path=path, name=self.name))
self.remote_command(['sudo', 'rm', path])
def remote_command(self, command):
ssh_cmd = ['ssh', '-i', self.keyfile,
'-p', str(self.port),
self.username + '@' + self.address,
'--'] + command
log_check_call(ssh_cmd)
@contextmanager
def connect_pyro(host, port):
import Pyro4
server_uri = 'PYRO:server@{host}:{port}'.format(host=host, port=port)
connection = Pyro4.Proxy(server_uri)
log.debug('Connecting to RPC daemon')
connected = False
try:
remaining_retries = 5
while not connected:
try:
connection.ping()
connected = True
except (Pyro4.errors.ConnectionClosedError, Pyro4.errors.CommunicationError):
if remaining_retries > 0:
remaining_retries -= 1
from time import sleep
sleep(2)
else:
raise
yield connection
finally:
if connected:
log.debug('Stopping RPC daemon')
connection.stop()
connection._pyroRelease()
else:
log.warn('Unable to stop RPC daemon, it might still be running on the server')