# -*- coding: utf-8 -*- # # Copyright (C) 2015 GNS3 Technologies Inc. # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . """ Set up and run the server. """ import os import sys import signal import asyncio import aiohttp import functools import types import time import atexit from .web.route import Route from .web.request_handler import RequestHandler from .config import Config from .modules import MODULES from .modules.port_manager import PortManager # do not delete this import import gns3server.handlers import logging log = logging.getLogger(__name__) class Server: def __init__(self, host, port): self._host = host self._port = port self._loop = None self._handler = None self._start_time = time.time() self._port_manager = PortManager(host) @staticmethod def instance(host=None, port=None): """ Singleton to return only one instance of Server. :returns: instance of Server """ if not hasattr(Server, "_instance") or Server._instance is None: assert host is not None assert port is not None Server._instance = Server(host, port) return Server._instance @asyncio.coroutine def _run_application(self, handler, ssl_context=None): try: server = yield from self._loop.create_server(handler, self._host, self._port, ssl=ssl_context) except OSError as e: log.critical("Could not start the server: {}".format(e)) self._loop.stop() return return server @asyncio.coroutine def shutdown_server(self): """ Cleanly shutdown the server. """ if self._handler: yield from self._handler.finish_connections() self._handler = None for module in MODULES: log.debug("Unloading module {}".format(module.__name__)) m = module.instance() yield from m.unload() if self._port_manager.tcp_ports: log.warning("TCP ports are still used {}".format(self._port_manager.tcp_ports)) if self._port_manager.udp_ports: log.warning("UDP ports are still used {}".format(self._port_manager.udp_ports)) self._loop.stop() def _signal_handling(self): def signal_handler(signame): log.warning("Server has got signal {}, exiting...".format(signame)) asyncio.async(self.shutdown_server()) signals = ["SIGTERM", "SIGINT"] if sys.platform.startswith("win"): signals.extend(["SIGBREAK"]) else: signals.extend(["SIGHUP", "SIGQUIT"]) for signal_name in signals: callback = functools.partial(signal_handler, signal_name) if sys.platform.startswith("win"): # add_signal_handler() is not yet supported on Windows signal.signal(getattr(signal, signal_name), callback) else: self._loop.add_signal_handler(getattr(signal, signal_name), callback) def _reload_hook(self): @asyncio.coroutine def reload(): log.info("Reloading") yield from self.shutdown_server() os.execv(sys.executable, [sys.executable] + sys.argv) # code extracted from tornado for module in sys.modules.values(): # Some modules play games with sys.modules (e.g. email/__init__.py # in the standard library), and occasionally this can cause strange # failures in getattr. Just ignore anything that's not an ordinary # module. if not isinstance(module, types.ModuleType): continue path = getattr(module, "__file__", None) if not path: continue if path.endswith(".pyc") or path.endswith(".pyo"): path = path[:-1] modified = os.stat(path).st_mtime if modified > self._start_time: log.debug("File {} has been modified".format(path)) asyncio.async(reload()) self._loop.call_later(1, self._reload_hook) def _create_ssl_context(self, server_config): import ssl ssl_context = ssl.SSLContext(ssl.PROTOCOL_SSLv23) certfile = server_config["certfile"] certkey = server_config["certkey"] try: ssl_context.load_cert_chain(certfile, certkey) except FileNotFoundError: log.critical("Could not find the SSL certfile or certkey") raise SystemExit except ssl.SSLError as e: log.critical("SSL error: {}".format(e)) raise SystemExit log.info("SSL is enabled") return ssl_context @asyncio.coroutine def start_shell(self): try: from ptpython.repl import embed except ImportError: log.error("Unable to start a shell: the ptpython module must be installed!") return yield from embed(globals(), locals(), return_asyncio_coroutine=True, patch_stdout=True) def _exit_handling(self): """ Makes sure the asyncio loop is closed. """ def close_asyncio_loop(): loop = None try: loop = asyncio.get_event_loop() except AttributeError: pass if loop is not None: loop.close() atexit.register(close_asyncio_loop) def run(self): """ Starts the server. """ logger = logging.getLogger("asyncio") logger.setLevel(logging.WARNING) server_config = Config.instance().get_section_config("Server") if sys.platform.startswith("win"): # use the Proactor event loop on Windows loop = asyncio.ProactorEventLoop() # Add a periodic callback to give a chance to process signals on Windows # because asyncio.add_signal_handler() is not supported yet on that platform # otherwise the loop runs outside of signal module's ability to trap signals. def wakeup(): loop.call_later(0.5, wakeup) loop.call_later(0.5, wakeup) asyncio.set_event_loop(loop) ssl_context = None if server_config.getboolean("ssl"): if sys.platform.startswith("win"): log.critical("SSL mode is not supported on Windows") raise SystemExit ssl_context = self._create_ssl_context(server_config) self._loop = asyncio.get_event_loop() # Asyncio will raise error if coroutine is not called self._loop.set_debug(True) app = aiohttp.web.Application() for method, route, handler in Route.get_routes(): log.debug("Adding route: {} {}".format(method, route)) app.router.add_route(method, route, handler) for module in MODULES: log.debug("Loading module {}".format(module.__name__)) m = module.instance() m.port_manager = self._port_manager log.info("Starting server on {}:{}".format(self._host, self._port)) self._handler = app.make_handler(handler=RequestHandler) server = self._run_application(self._handler, ssl_context) self._loop.run_until_complete(server) self._signal_handling() self._exit_handling() if server_config.getboolean("live"): log.info("Code live reload is enabled, watching for file changes") self._loop.call_later(1, self._reload_hook) if server_config.getboolean("shell"): asyncio.async(self.start_shell()) try: self._loop.run_forever() except TypeError as e: # This is to ignore an asyncio.windows_events exception # on Windows when the process gets the SIGBREAK signal # TypeError: async() takes 1 positional argument but 3 were given log.warning("TypeError exception in the loop {}".format(e)) finally: if self._handler and self._loop.is_running(): self._loop.run_until_complete(self._handler.finish_connections()) server.close() if self._loop.is_running(): self._loop.run_until_complete(app.finish())