Django Middleware Demos

📖 Overview

This repo demonstrates two real-world Django custom middleware patterns — how middleware participates in the request-response lifecycle, blocks requests during maintenance, and how initialization, pre-processing, view execution, and post-processing all connect together.

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📁 Project Structure

django-middleware-demos/
├── execution_flow/
│   ├── middleware.py       # ExecutionFlowMiddleware — logs request lifecycle
│   ├── views.py            # welcome_view — returns styled HTML response
│   ├── urls.py             # URL routing
│   └── settings.py         # MIDDLEWARE list config
│
└── maintenance_mode/
    ├── middleware.py       # AppMaintenanceMiddleware — blocks all requests
    ├── views.py            # home_page — blocked during maintenance
    └── urls.py             # URL routing

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🔁 Project 1 — Execution Flow Middleware

Shows how Django middleware wraps around every request-response cycle.

Server starts
    └── Middleware.__init__()           ← runs once at startup
         └── Request received
              └── Middleware.__call__() — pre-processing
                   └── View function executes
                        └── Middleware.__call__() — post-processing
                             └── Response returned

🧠 Key Concepts

Method	When it runs
__init__	Once — when the server starts
__call__ (before get_response)	Every request — pre-processing
get_response(request)	Calls the actual view
__call__ (after get_response)	Every request — post-processing

⚙️ Register in settings.py

MIDDLEWARE = [
    ...
    'execution_flow.middleware.ExecutionFlowMiddleware',
]

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🚧 Project 2 — Maintenance Mode Middleware

Shows how middleware can short-circuit the request pipeline entirely — the view function never executes.

Request received
    └── AppMaintenanceMiddleware.__call__()
         └── Returns maintenance HttpResponse directly
              └── View is never called

🧠 Key Concepts

Behavior	How it works
Blocks all routes	__call__ returns response before get_response is called
View never runs	No self.get_response(request) call
Easy to toggle	Comment out middleware in settings.py to restore normal flow

⚙️ Register in settings.py

MIDDLEWARE = [
    ...
    'maintenance_mode.middleware.AppMaintenanceMiddleware',
]

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⚙️ Setup

git clone https://github.com/your-username/django-middleware-demos
cd django-middleware-demos
pip install django
python manage.py runserver

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👨‍💻 Author

Sajjad Ali

Python Full Stack Developer

Building Django projects while exploring backend architecture and middleware concepts.

📄 License

MIT