lecroissant2003/fms-backend repository overview

⁠Factory Management System (FMS) - Backend Microservice

High-performance, asynchronous Django 5 REST API & WebSocket backend powering the Factory Management System (FMS). Built with Django REST Framework, Django Channels, Redis caching/channel layer, and Google OAuth2.

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⁠🏗️ Architecture & Core Modules

The backend is composed of domain-driven Django applications:

• main: User management, custom authentication, role-based permissions (Admin, Manager, Supervisor).
• core: Organization structure, departments, and workshop locations.
• labor: Employee skill matrix, work shifts, and labor tracking.
• project: Project lifecycles, milestone tracking, and task assignments.
• product: Product catalogs, manufacturing processes, and BOM (Bill of Materials).
• inventory: Suppliers, raw materials, stock levels, and consumption tracking.
• production: Production lines, machine states, and manufacturing schedules.

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⁠🔐 Google OAuth2 & Authentication Flow

• Pre-Registered Account Enforcement: Uses a CustomSocialAccountAdapter extending django-allauth. Automatic signup is disabled (SOCIALACCOUNT_AUTO_SIGNUP = False). Only existing system users with matching Google emails are allowed access; unauthenticated attempts return HTTP 403 with administrator instructions.
• JWT Token Management: Powered by rest_framework_simplejwt & dj-rest-auth.
  • Token Rotation: ROTATE_REFRESH_TOKENS = True
  • Blacklisting: TOKEN_BLACKLIST_ENABLED = True
  • Lifetimes: 30-minute access and refresh tokens.
  • Endpoints: /api/token/, /api/token/refresh/, /api/token/blacklist/, /api/rest-auth/google/.

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⁠⚡ WebSockets & Asynchronous Messaging

• ASGI Stack: Uses ProtocolTypeRouter (backend.asgi.application) combining HTTP and WebSocket protocols.
• Handshake Authentication: Custom JWTAuthMiddleware and ConsumerBlock validate SimpleJWT access tokens upon initial WebSocket handshake connection.
• Channel Layer: Backed by channels_redis.core.RedisChannelLayer for scalable multi-node message broadcasting.
• Real-Time Security: Performs server-side DRF permission checks (check_object_permission) on WebSocket message payloads before sending updates to connected clients.

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⁠📡 Event Listening & Django Signals

• Automated Data Sync: Implements a generic model change factory create_model_change_signal listening on post_save and post_delete model signals.
• Real-Time Serialization: Automatically serializes model instance mutations (created, updated, deleted) using DRF serializers.
• Live Push: Broadcasts events asynchronously (async_to_sync) over Redis Channel Layer groups directly to active frontend WebSocket listeners.

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⁠🚀 Backend Caching & Session Storage

Configured using django-redis with ZlibCompressor compression and JSONSerializer:

1. Default Cache DB (redis://.../1):
   • Low-level object and view cache (KEY_PREFIX: fms).
   • Default TTL: 300 seconds.
   • Max connection pool size: 20 connections.
   • Resilience: IGNORE_EXCEPTIONS = True ensures graceful fallback to standard database queries if Redis is offline.
2. Session Storage DB (redis://.../2):
   • SESSION_ENGINE = "django.contrib.sessions.backends.cache"
   • Dedicated Redis logical database (KEY_PREFIX: fms-session).
   • Session TTL: 24 hours (86400 seconds).

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⁠📊 Observability & Health Probes

• Metrics Scrape: Integrated django_prometheus middleware exposing Prometheus metrics at /metrics.
• Health Check: Dedicated probe endpoint at /api/health/ handled by HealthCheckMiddleware (bypasses ALLOWED_HOSTS for Kubernetes / Docker compose probes).
• Execution Logging: RequestTimeLoggingMiddleware records execution latency in JSON format to /app/logs/ and outputs colorized rich console logs during development.

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⁠🛠️ Environment Variables Reference