Ich bin neu bei Stack Overflow (obwohl ich schon lange "Stalker" war!) Also bitte sei sanft mit mir!Python 3 websockets - Nachricht senden vor dem Schließen der Verbindung
Ich versuche Python zu lernen, insbesondere Asyncio mit Websockets.
Nachdem ich das Internet nach Beispielen/Tutorials durchforstet habe, habe ich die folgende kleine Chat-Anwendung zusammengestellt und könnte einige Ratschläge geben, bevor es sperriger wird (mehr Befehle usw.) und schwierig zu refaktorieren ist.
Meine Hauptfrage ist, warum (beim Senden des DISCONNECT-Befehls) benötigt es die asyncio.sleep (0), um die Trennungsverifizierung zu senden, BEVOR die Verbindung geschlossen wird?
Sonst bin ich auf der richtigen Spur mit der Struktur hier?
Ich fühle, dass es zu viel async/warte, aber ich kann mich nicht ganz darum kümmern warum.
Aus stundenlangen Tutorials und S/O-Posts zu schauen, scheint an dieser Stelle nicht gerade hilfreich zu sein, also dachte ich, ich würde direkt einen Expertenrat bekommen!
Hier gehen wir, einfache WS-Server, die auf "Nick", "msg" reagiert, "Test" & "trennen" -Befehle. Kein Präfix erforderlich, d. H. "Nick Rachel".
import asyncio
import websockets
import sys
class ChatServer:
def __init__(self):
print("Chat Server Starting..")
self.Clients = set()
if sys.platform == 'win32':
self.loop = asyncio.ProactorEventLoop()
asyncio.set_event_loop(self.loop)
else:
self.loop = asyncio.get_event_loop()
def run(self):
start_server = websockets.serve(self.listen, '0.0.0.0', 8080)
try:
self.loop.run_until_complete(start_server)
print("Chat Server Running!")
self.loop.run_forever()
except:
print("Chat Server Error!")
async def listen(self, websocket, path):
client = Client(websocket=websocket)
sender_task = asyncio.ensure_future(self.handle_outgoing_queue(client))
self.Clients.add(client)
print("+ connection: " + str(len(self.Clients)))
while True:
try:
msg = await websocket.recv()
if msg is None:
break
await self.handle_message(client, msg)
except websockets.exceptions.ConnectionClosed:
break
self.Clients.remove(client)
print("- connection: " + str(len(self.Clients)))
async def handle_outgoing_queue(self, client):
while client.websocket.open:
msg = await client.outbox.get()
await client.websocket.send(msg)
async def handle_message(self, client, data):
strdata = data.split(" ")
_cmd = strdata[0].lower()
try:
# Check to see if the command exists. Otherwise, AttributeError is thrown.
func = getattr(self, "cmd_" + _cmd)
try:
await func(client, param, strdata)
except IndexError:
await client.send("Not enough parameters!")
except AttributeError:
await client.send("Command '%s' does not exist!" % (_cmd))
# SERVER COMMANDS
async def cmd_nick(self, client, param, strdata):
# This command needs a parameter (with at least one character). If not supplied, IndexError is raised
# Is there a cleaner way of doing this? Otherwise it'll need to reside within all functions that require a param
test = param[1][0]
# If we've reached this point there's definitely a parameter supplied
client.Nick = param[1]
await client.send("Your nickname is now %s" % (client.Nick))
async def cmd_msg(self, client, param, strdata):
# This command needs a parameter (with at least one character). If not supplied, IndexError is raised
# Is there a cleaner way of doing this? Otherwise it'll need to reside within all functions that require a param
test = param[1][0]
# If we've reached this point there's definitely a parameter supplied
message = strdata.split(" ",1)[1]
# Before we proceed, do we have a nickname?
if client.Nick == None:
await client.send("You must choose a nickname before sending messages!")
return
for each in self.Clients:
await each.send("%s says: %s" % (client.Nick, message))
async def cmd_test(self, client, param, strdata):
# This command doesn't need a parameter, so simply let the client know they issued this command successfully.
await client.send("Test command reply!")
async def cmd_disconnect(self, client, param, strdata):
# This command doesn't need a parameter, so simply let the client know they issued this command successfully.
await client.send("DISCONNECTING")
await asyncio.sleep(0) # If this isn't here we don't receive the "disconnecting" message - just an exception in "handle_outgoing_queue" ?
await client.websocket.close()
class Client():
def __init__(self, websocket=None):
self.websocket = websocket
self.IPAddress = websocket.remote_address[0]
self.Port = websocket.remote_address[1]
self.Nick = None
self.outbox = asyncio.Queue()
async def send(self, data):
await self.outbox.put(data)
chat = ChatServer()
chat.run()
Es gibt ein definiertes Protokoll zum Schließen einer WebSocket-Verbindung. https://tools.ietf.org/html/rfc6455#section-5.5.1 –