django-inject-message

Inject HTML messages into Django HTTP responses based on URL patterns, anchor sequences, and activity rules.

Purpose

Manage banners, alerts, and notices from the database (or admin) without editing templates. Messages are inserted into rendered HTML responses by middleware after matching:

• URL path patterns
• Anchor sequences in the HTML body (e.g. <body>, </header>)
• Activity window (active_from / active_until)
• Optional cron schedule (weekends, business hours, etc.)
• Severity level with built-in CSS styling

Installation

pip install django-inject-message

Add to INSTALLED_APPS:

INSTALLED_APPS = [
    # ...
    "django_boosted",
    "inject_message",
]

Add middleware (before compression middleware if you use GZip):

MIDDLEWARE = [
    # ...
    "django.contrib.auth.middleware.AuthenticationMiddleware",
    "django_boosted.middleware.CurrentUserMiddleware",
    "inject_message.middleware.InjectMessageMiddleware",
]

Run migrations:

python manage.py migrate inject_message

Quick start

1. Create a message and injection rule

from inject_message.models import Message, MessageInjection, MessageLevel

message = Message.objects.create(
    label="Maintenance",
    content="<strong>Scheduled maintenance tonight at 22:00.</strong>",
    level=MessageLevel.WARNING,
)

MessageInjection.objects.create(
    message=message,
    url_pattern="/dashboard/",
    after_sequence="<body>",
)

2. Or use the Django admin

Open /admin/ and manage Messages with inline Message injections. Each message supports:

• Content and severity level (debug, info, success, warning, error)
• Activity dates and cron schedule (with presets for weekends / weekdays)
• Multiple injection rules per message

3. Schedule examples

from inject_message import SCHEDULE_WEEKENDS, SCHEDULE_WEEKDAYS, SCHEDULE_BUSINESS_HOURS

Message.objects.create(
    label="Weekend promo",
    content="Special offer this weekend!",
    level=MessageLevel.SUCCESS,
    schedule=SCHEDULE_WEEKENDS,
)

Cron format: minute hour day month weekday (e.g. * * * * 0,6 for weekends).

Demo (development)

This repository includes a demo app under tests/demo/:

Seed demo data:

PYTHONPATH=src python manage.py seed_demo_messages --clear
PYTHONPATH=src python manage.py runserver

Security

Message content is injected as HTML. Only trusted staff should edit messages in the admin.

Development

PYTHONPATH=src python -m pytest tests/ -v
PYTHONPATH=src python manage.py migrate

License

MIT