WIP: Websockets

Procfile

@@ -1,5 +1,5 @@
 # Web process: gunicorn
-web: env/bin/gunicorn --chdir $APP_HOME/src/backend/InvenTree -c src/backend/InvenTree/gunicorn.conf.py InvenTree.wsgi -b 0.0.0.0:$PORT
+web: env/bin/gunicorn --chdir $APP_HOME/src/backend/InvenTree -c src/backend/InvenTree/gunicorn.conf.py InvenTree.asgi -b 0.0.0.0:$PORT -k uvicorn_worker.UvicornWorker
 # Worker process: qcluster
 worker: env/bin/python src/backend/InvenTree/manage.py qcluster
 # Invoke commands

contrib/container/Dockerfile

@@ -139,7 +139,7 @@ COPY src/backend/requirements.txt ${INVENTREE_BACKEND_DIR}/requirements.txt
 COPY --from=frontend ${INVENTREE_BACKEND_DIR}/InvenTree/web/static/web ${INVENTREE_BACKEND_DIR}/InvenTree/web/static/web
 
 # Launch the production server
-CMD gunicorn -c ./gunicorn.conf.py InvenTree.wsgi -b 0.0.0.0:8000 --chdir ${INVENTREE_BACKEND_DIR}/InvenTree
+CMD gunicorn -c ./gunicorn.conf.py InvenTree.asgi -b 0.0.0.0:8000 --chdir ${INVENTREE_BACKEND_DIR}/InvenTree -k uvicorn_worker.UvicornWorker
 
 FROM inventree_base AS dev
 

contrib/container/requirements.in

@@ -13,6 +13,7 @@ mariadb>=1.1.8
 
 # gunicorn web server
 gunicorn>=22.0.0
+uvicorn-worker                  # ASGI worker for gunicorn
 
 # LDAP required packages
 django-auth-ldap                # Django integration for ldap auth

contrib/container/requirements.txt

@@ -4,6 +4,10 @@ asgiref==3.8.1 \
     --hash=sha256:3e1e3ecc849832fe52ccf2cb6686b7a55f82bb1d6aee72a58826471390335e47 \
     --hash=sha256:c343bd80a0bec947a9860adb4c432ffa7db769836c64238fc34bdc3fec84d590
     # via django
+click==8.1.7 \
+    --hash=sha256:ae74fb96c20a0277a1d615f1e4d73c8414f5a98db8b799a7931d1582f3390c28 \
+    --hash=sha256:ca9853ad459e787e2192211578cc907e7594e294c7ccc834310722b41b9ca6de
+    # via uvicorn
 django==4.2.15 \
     --hash=sha256:61ee4a130efb8c451ef3467c67ca99fdce400fedd768634efc86a68c18d80d30 \
     --hash=sha256:c77f926b81129493961e19c0e02188f8d07c112a1162df69bfab178ae447f94a
@@ -17,7 +21,13 @@ django-auth-ldap==4.8.0 \
 gunicorn==23.0.0 \
     --hash=sha256:ec400d38950de4dfd418cff8328b2c8faed0edb0d517d3394e457c317908ca4d \
     --hash=sha256:f014447a0101dc57e294f6c18ca6b40227a4c90e9bdb586042628030cba004ec
-    # via -r contrib/container/requirements.in
+    # via
+    #   -r contrib/container/requirements.in
+    #   uvicorn-worker
+h11==0.14.0 \
+    --hash=sha256:8f19fbbe99e72420ff35c00b27a34cb9937e902a8b810e2c88300c6f0a3b699d \
+    --hash=sha256:e3fe4ac4b851c468cc8363d500db52c2ead036020723024a109d37346efaa761
+    # via uvicorn
 invoke==2.2.0 \
     --hash=sha256:6ea924cc53d4f78e3d98bc436b08069a03077e6f85ad1ddaa8a116d7dad15820 \
     --hash=sha256:ee6cbb101af1a859c7fe84f2a264c059020b0cb7fe3535f9424300ab568f6bd5
@@ -219,6 +229,14 @@ uv==0.3.0 \
     --hash=sha256:d3da56b87ec5aa4f2ae572127c754655bad3820dd41a4d37ed4d5e2f67035990 \
     --hash=sha256:d87ff76da5128036c05db0291db7510a85cb8efb86538e8f49adc8074bb292f0
     # via -r contrib/container/requirements.in
+uvicorn==0.30.6 \
+    --hash=sha256:4b15decdda1e72be08209e860a1e10e92439ad5b97cf44cc945fcbee66fc5788 \
+    --hash=sha256:65fd46fe3fda5bdc1b03b94eb634923ff18cd35b2f084813ea79d1f103f711b5
+    # via uvicorn-worker
+uvicorn-worker==0.2.0 \
+    --hash=sha256:65dcef25ab80a62e0919640f9582216ee05b3bb1dc2f0e58b354ca0511c398fb \
+    --hash=sha256:f6894544391796be6eeed37d48cae9d7739e5a105f7e37061eccef2eac5a0295
+    # via -r contrib/container/requirements.in
 wheel==0.44.0 \
     --hash=sha256:2376a90c98cc337d18623527a97c31797bd02bad0033d41547043a1cbfbe448f \
     --hash=sha256:a29c3f2817e95ab89aa4660681ad547c0e9547f20e75b0562fe7723c9a2a9d49

contrib/deploy/supervisord.conf

@@ -24,7 +24,7 @@ port = 127.0.0.1:9001
 [program:inventree-server]
 user=inventree
 directory=/home/inventree/src/InvenTree
-command=/home/inventree/env/bin/gunicorn -c gunicorn.conf.py InvenTree.wsgi
+command=/home/inventree/env/bin/gunicorn -c gunicorn.conf.py InvenTree.asgi -k uvicorn_worker.UvicornWorker
 startsecs=10
 autostart=true
 autorestart=true

src/backend/InvenTree/InvenTree/asgi.py

@@ -0,0 +1,28 @@
+"""ASGI config for InvenTree project.
+
+It exposes the ASGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/4.1/howto/deployment/asgi/
+"""
+
+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', 'InvenTree.settings'
+)  # pragma: no cover
+
+from InvenTree import routing
+
+application = ProtocolTypeRouter({
+    'http': get_asgi_application(),
+    'websocket': AllowedHostsOriginValidator(
+        AuthMiddlewareStack(URLRouter(routing.websocket_urlpatterns))
+    ),
+})

src/backend/InvenTree/InvenTree/routing.py

@@ -0,0 +1,11 @@
+"""Async routings for InvenTree."""
+
+from django.urls import path
+
+from channels.routing import URLRouter
+
+from web.consumers import InvenTreeConsumer
+
+websocket_urlpatterns = [
+    path('ws/', URLRouter([path('page/<url_name>/', InvenTreeConsumer.as_asgi())]))
+]

src/backend/InvenTree/InvenTree/settings.py

@@ -22,7 +22,12 @@
 import pytz
 from dotenv import load_dotenv
 
-from InvenTree.cache import get_cache_config, is_global_cache_enabled
+from InvenTree.cache import (
+    cache_host,
+    cache_port,
+    get_cache_config,
+    is_global_cache_enabled,
+)
 from InvenTree.config import get_boolean_setting, get_custom_file, get_setting
 from InvenTree.ready import isInMainThread
 from InvenTree.sentry import default_sentry_dsn, init_sentry
@@ -184,6 +189,7 @@
 )
 
 INSTALLED_APPS = [
+    'daphne',  # ASGI enabled dev server
     # Admin site integration
     'django.contrib.admin',
     # InvenTree apps
@@ -239,6 +245,7 @@
     'dj_rest_auth.registration',  # Registration APIs - dj-rest-auth'
     'drf_spectacular',  # API documentation
     'django_ical',  # For exporting calendars
+    'channels',  # websockets
 ]
 
 MIDDLEWARE = CONFIG.get(
@@ -516,6 +523,7 @@
 
 # WSGI default setting
 WSGI_APPLICATION = 'InvenTree.wsgi.application'
+ASGI_APPLICATION = 'InvenTree.asgi.application'
 
 """
 Configure the database backend based on the user-specified values.
@@ -842,6 +850,17 @@
     # as well
     Q_CLUSTER['django_redis'] = 'worker'
 
+# Settings for channels
+if GLOBAL_CACHE_ENABLED:  # pragma: no cover
+    CHANNEL_LAYERS = {
+        'default': {
+            'BACKEND': 'channels_redis.core.RedisChannelLayer',
+            'CONFIG': {'hosts': [cache_host(), cache_port()]},
+        }
+    }
+else:
+    CHANNEL_LAYERS = {'default': {'BACKEND': 'channels.layers.InMemoryChannelLayer'}}
+
 # database user sessions
 SESSION_ENGINE = 'user_sessions.backends.db'
 LOGOUT_REDIRECT_URL = get_setting(

src/backend/InvenTree/web/consumers.py

@@ -0,0 +1,82 @@
+"""Websocket consumers for web app."""
+
+import json
+
+from asgiref.sync import async_to_sync
+from channels.generic.websocket import JsonWebsocketConsumer
+
+
+class InvenTreeConsumer(JsonWebsocketConsumer):
+    """This consumer is used to enable page attendance widgets."""
+
+    def __init__(self, *args, **kwargs):
+        """Set up context."""
+        super().__init__(args, kwargs)
+        self.user = None
+
+    def connect(self):
+        """Join a user to a page."""
+        user = self.scope.get('user')
+        if not user or not user.is_authenticated:
+            self.close()
+            return
+        self.user = user
+        self.accept()
+
+        from django.contrib.auth.models import User
+
+        from InvenTree.serializers import UserSerializer
+
+        self.room_name = self.scope['url_route']['kwargs']['url_name']
+        self.room_group_name = f'chat_{self.room_name}'
+        # Join room group
+        async_to_sync(self.channel_layer.group_add)(
+            self.room_group_name, self.channel_name
+        )
+
+        # Announce all users
+        instances = User.objects.all()
+        self.send_json({
+            'type': 'users',
+            'users': UserSerializer(instances, many=True).data,
+        })
+
+    def disconnect(self, code):
+        """Remove user from a page."""
+        async_to_sync(self.channel_layer.group_discard)(
+            self.room_group_name, self.channel_name
+        )
+        return super().disconnect(code)
+
+    def receive_json(self, content, **kwargs):
+        """Handler for processing incoming messages."""
+        message_type = content.get('type', None)
+        message = content.get('message', None)
+
+        async_to_sync(self.channel_layer.group_send)(
+            self.room_group_name,
+            {
+                'type': 'chat_message',
+                'message': message,
+                'user': self.user.get_username(),
+            },
+        )
+
+        if message_type == '#TODO':
+            # TODO: implement this
+            ...
+        return super().receive_json(content, **kwargs)
+
+    # Receive message from room group
+    def chat_message(self, event):
+        """Send message to WebSocket."""
+        message = event['message']
+
+        # Send message to WebSocket
+        self.send(
+            text_data=json.dumps({
+                'type': 'chat_message',
+                'message': message,
+                'user': event['user'],
+            })
+        )

src/backend/requirements-dev.txt

@@ -182,7 +182,9 @@ charset-normalizer==3.3.2 \
 click==8.1.7 \
     --hash=sha256:ae74fb96c20a0277a1d615f1e4d73c8414f5a98db8b799a7931d1582f3390c28 \
     --hash=sha256:ca9853ad459e787e2192211578cc907e7594e294c7ccc834310722b41b9ca6de
-    # via pip-tools
+    # via
+    #   -c src/backend/requirements.txt
+    #   pip-tools
 coverage[toml]==7.6.1 \
     --hash=sha256:06a737c882bd26d0d6ee7269b20b12f14a8704807a01056c80bb881a4b2ce6ca \
     --hash=sha256:07e2ca0ad381b91350c0ed49d52699b625aab2b44b65e1b4e02fa9df0e92ad2d \

src/backend/requirements.in

@@ -1,8 +1,10 @@
 # Please keep this list sorted - if you pin a version provide a reason
 Django<5.0                              # Django package
+channels[daphne]                        # Websockers
+channels_redis                          # Websockets with Redis
 coreapi                                 # API documentation for djangorestframework
 cryptography>=40.0.0,!=40.0.2           # Core cryptographic functionality
-django-allauth[openid,saml]               # SSO for external providers via OpenID
+django-allauth[openid,saml]             # SSO for external providers via OpenID
 django-allauth-2fa                      # MFA / 2FA
 django-cleanup                          # Automated deletion of old / unused uploaded files
 django-cors-headers                     # CORS headers extension for DRF
@@ -51,6 +53,7 @@ regex                                   # Advanced regular expressions
 sentry-sdk                              # Error reporting (optional)
 setuptools                              # Standard dependency
 tablib[xls,xlsx,yaml]                   # Support for XLS and XLSX formats
+uvicorn-worker                          # ASGI worker for gunicorn
 weasyprint                              # PDF generation
 whitenoise                              # Enhanced static file serving