r"""server is a module that enables using python through a web-server. This module can be used as the entry point to the application. In that case, it sets up a web-server. web-pages are determines by the command line arguments passed in. Use "--help" to list the supported arguments. """ import argparse import asyncio import logging from wslink import websocket as wsl from wslink import backends ws_server = None # ============================================================================= # Setup default arguments to be parsed # -s, --nosignalhandlers # -d, --debug # -i, --host localhost # -p, --port 8080 # -t, --timeout 300 (seconds) # -c, --content '/www' (No content means WebSocket only) # -a, --authKey vtkweb-secret # ============================================================================= def add_arguments(parser): """ Add arguments known to this module. parser must be argparse.ArgumentParser instance. """ parser.add_argument( "-d", "--debug", help="log debugging messages to stdout", action="store_true" ) parser.add_argument( "-s", "--nosignalhandlers", help="Prevent installation of signal handlers so server can be started inside a thread.", action="store_true", ) parser.add_argument( "-i", "--host", type=str, default="localhost", help="the interface for the web-server to listen on (default: 0.0.0.0)", ) parser.add_argument( "-p", "--port", type=int, default=8080, help="port number for the web-server to listen on (default: 8080)", ) parser.add_argument( "-t", "--timeout", type=int, default=300, help="timeout for reaping process on idle in seconds (default: 300s, 0 to disable)", ) parser.add_argument( "-c", "--content", default="", help="root for web-pages to serve (default: none)", ) parser.add_argument( "-a", "--authKey", default="wslink-secret", help="Authentication key for clients to connect to the WebSocket.", ) parser.add_argument( "-ws", "--ws-endpoint", type=str, default="ws", dest="ws", help="Specify WebSocket endpoint. (e.g. foo/bar/ws, Default: ws)", ) parser.add_argument( "--no-ws-endpoint", action="store_true", dest="nows", help="If provided, disables the websocket endpoint", ) parser.add_argument( "--fs-endpoints", default="", dest="fsEndpoints", help="add another fs location to a specific endpoint (i.e: data=/Users/seb/Download|images=/Users/seb/Pictures)", ) parser.add_argument( "--reverse-url", dest="reverse_url", help="Make the server act as a client to connect to a ws relay", ) parser.add_argument( "--ssl", type=str, default="", dest="ssl", help="add a tuple file [certificate, key] (i.e: --ssl 'certificate,key') or adhoc string to generate temporary certificate (i.e: --ssl 'adhoc')", ) return parser # ============================================================================= # Parse arguments and start webserver # ============================================================================= def start(argv=None, protocol=wsl.ServerProtocol, description="wslink web-server"): """ Sets up the web-server using with __name__ == '__main__'. This can also be called directly. Pass the optional protocol to override the protocol used. Default is ServerProtocol. """ parser = argparse.ArgumentParser(description=description) add_arguments(parser) args = parser.parse_args(argv) # configure protocol, if available try: protocol.configure(args) except AttributeError: pass start_webserver(options=args, protocol=protocol) # ============================================================================= # Stop webserver # ============================================================================= def stop_webserver(): if ws_server: loop = asyncio.get_event_loop() return loop.create_task(ws_server.stop()) # ============================================================================= # Get webserver port (useful when 0 is provided and a dynamic one was picked) # ============================================================================= def get_port(): if ws_server: return ws_server.get_port() return -1 # ============================================================================= # Given a configuration file, create and return a webserver # # config = { # "host": "0.0.0.0", # "port": 8081 # "ws": { # "/ws": serverProtocolInstance, # ... # }, # static_routes: { # '/static': .../path/to/files, # ... # }, # } # ============================================================================= def create_webserver(server_config, backend="aiohttp"): return backends.create_webserver(server_config, backend=backend) # ============================================================================= # Generate a webserver config from command line options, create a webserver, # and start it. # ============================================================================= def start_webserver( options, protocol=wsl.ServerProtocol, disableLogging=False, backend="aiohttp", exec_mode="main", **kwargs, ): """ Starts the web-server with the given protocol. Options must be an object with the following members: options.host : the interface for the web-server to listen on options.port : port number for the web-server to listen on options.timeout : timeout for reaping process on idle in seconds options.content : root for web-pages to serve. """ global ws_server # Create default or custom ServerProtocol wslinkServer = protocol() if disableLogging: logging_level = None elif options.debug: logging_level = logging.DEBUG else: logging_level = logging.ERROR if options.reverse_url: server_config = { "reverse_url": options.reverse_url, "ws_protocol": wslinkServer, "logging_level": logging_level, } else: server_config = { "host": options.host, "port": options.port, "timeout": options.timeout, "logging_level": logging_level, } # Configure websocket endpoint if not options.nows: server_config["ws"] = {} server_config["ws"][options.ws] = wslinkServer # Configure default static route if --content requested if len(options.content) > 0: server_config["static"] = {} # Static HTTP + WebSocket server_config["static"]["/"] = options.content # Configure any other static routes if len(options.fsEndpoints) > 3: if "static" not in server_config: server_config["static"] = {} for fsResourceInfo in options.fsEndpoints.split("|"): infoSplit = fsResourceInfo.split("=") server_config["static"][infoSplit[0]] = infoSplit[1] # Confifugre SSL if len(options.ssl) > 0: from .ssl_context import generate_ssl_pair, ssl if options.ssl == "adhoc": options.ssl = generate_ssl_pair(server_config["host"]) else: tokens = options.ssl.split(",") if len(tokens) != 2: raise Exception( f'ssl configure must be "adhoc" or a tuple of files "cert,key"' ) options.ssl = tokens cert, key = options.ssl context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER) context.load_cert_chain(cert, key) server_config["ssl"] = context server_config["handle_signals"] = not options.nosignalhandlers # Create the webserver and start it ws_server = create_webserver(server_config, backend=backend) # Once we have python 3.7 minimum, we can start the server with asyncio.run() # asyncio.run(ws_server.start()) # Until then, we can start the server this way loop = asyncio.get_event_loop() port_callback = None if hasattr(wslinkServer, "port_callback"): port_callback = wslinkServer.port_callback if hasattr(wslinkServer, "set_server"): wslinkServer.set_server(ws_server) def create_coroutine(): return ws_server.start(port_callback) def main_exec(): # Block until webapp exits try: loop.run_until_complete(create_coroutine()) except SystemExit: # backend gracefully exit (due to timeout or SIGINT/SIGTERM) pass def task_exec(): return loop.create_task(create_coroutine()) exec_modes = { "main": main_exec, "task": task_exec, "coroutine": create_coroutine, } if exec_mode not in exec_modes: raise Exception(f"Unknown exec_mode: {exec_mode}") return exec_modes[exec_mode]() if __name__ == "__main__": start()