add chat consumers.py, routing.py, add ws to asgi.py, update readme

chat-room/README.md

@@ -4,13 +4,24 @@
 ```bash
 cd chat-room/mysite/
 
+# init migrate
+python manage.py migrate
+
+# run app
 # (make sure at same level with manage.py)
 python3 manage.py runserver
 ```
 
+```bash
+# check DB
+sqlite3 db.sqlite3
+```
+
 ## Endpoints
 
 - http://127.0.0.1:8000/chat/
+  - http://127.0.0.1:8000/chat/lobby/
+
 - http://127.0.0.1:8000/admin/
 
 ## Ref

chat-room/doc/progress.md

@@ -0,0 +1,2 @@
+## 20240727
+- https://channels.readthedocs.io/en/latest/tutorial/part_2.html (to complete)

chat-room/mysite/chat/consumers.py

@@ -0,0 +1,26 @@
+import json
+
+from channels.generic.websocket import WebsocketConsumer
+
+
+# https://channels.readthedocs.io/en/latest/tutorial/part_2.html
+"""
+This is a synchronous WebSocket consumer 
+that accepts all connections, receives messages 
+from its client, and echos those messages back to the same client. 
+For now it does not broadcast messages to other clients in the same room.
+"""
+
+
+class ChatConsumer(WebsocketConsumer):
+    def connect(self):
+        self.accept()
+
+    def disconnect(self, close_code):
+        pass
+
+    def receive(self, text_data):
+        text_data_json = json.loads(text_data)
+        message = text_data_json["message"]
+
+        self.send(text_data=json.dumps({"message": message}))

chat-room/mysite/chat/routing.py

@@ -0,0 +1,7 @@
+from django.urls import re_path
+
+from . import consumers
+
+websocket_urlpatterns = [
+    re_path(r"ws/chat/(?P<room_name>\w+)/$", consumers.ChatConsumer.as_asgi()),
+]

chat-room/mysite/mysite/asgi.py

@@ -7,10 +7,48 @@
 https://docs.djangoproject.com/en/4.2/howto/deployment/asgi/
 """
 
+# https://channels.readthedocs.io/en/latest/tutorial/part_2.html
+
 import os
 
 from django.core.asgi import get_asgi_application
 
+from channels.auth import AuthMiddlewareStack
+from channels.routing import ProtocolTypeRouter, URLRouter
+from channels.security.websocket import AllowedHostsOriginValidator
+
 os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mysite.settings')
 
-application = get_asgi_application()
+#application = get_asgi_application()
+
+# Initialize Django ASGI application early to ensure the AppRegistry
+# is populated before importing code that may import ORM models.
+django_asgi_app = get_asgi_application()
+
+
+from ..chat.routing import websocket_urlpatterns
+
+"""
+This root routing configuration specifies that when a connection is made to the Channels development server, 
+the ProtocolTypeRouter will first inspect the type of connection. If it is a WebSocket connection (ws:// or wss://), 
+the connection will be given to the AuthMiddlewareStack.
+
+
+The AuthMiddlewareStack will populate the connection’s scope 
+with a reference to the currently authenticated user, 
+similar to how Django’s AuthenticationMiddleware populates 
+the request object of a view function with the currently authenticated user. 
+(Scopes will be discussed later in this tutorial.) 
+Then the connection will be given to the URLRouter.
+
+The URLRouter will examine the HTTP path of the connection to route it to a particular consumer,
+based on the provided url patterns.
+"""
+application = ProtocolTypeRouter(
+    {
+        "http": django_asgi_app,
+        "websocket": AllowedHostsOriginValidator(
+            AuthMiddlewareStack(URLRouter(websocket_urlpatterns))
+        ),
+    }
+)