django-run-context

Determine the context under which a Django project is being run.

Installation

pip install django-run-context

Supported contexts

get_run_context() returns one of:

Usage

Add it to your settings.py:

from django_run_context import get_run_context

RUN_CONTEXT = get_run_context()

and access it anywhere else in the project:

from django.conf import settings

print(settings.RUN_CONTEXT)

Why you might need this

By default manage.py runserver loads settings.py twice: once in the supervising process (which only watches the filesystem for changes) and again in the reloader-spawned process that actually serves requests. Anything printed from settings.py — for example diagnostics in DEBUG mode — therefore appears twice.

RUN_CONTEXT lets you emit such output exactly once, for example:

if DEBUG and RUN_CONTEXT != "runserver_reloader":
    import django
    import sys

    log.debug(f"Django version: {django.__version__}")
    log.debug(f"Python version: {sys.version}")
    log.debug(f"Django loaded from: {django.__file__}")
    log.debug(f"Using Path: {sys.path}")
    log.debug(f"Static root: {STATIC_ROOT}")
    log.debug(f"Static file dirs: {STATICFILES_DIRS}")
    log.debug(f"Installed apps: {INSTALLED_APPS}")
    log.debug(f"Database: {DATABASES['default']}")
    log.debug(f"Command line: {sys.argv}")

The supervising (reloader) process suppresses the output, and the real server prints it once — whether started with the reloader (the default) or with --noreload.

Start management commands clean

Management commands (migrate, shell, custom commands, ...) all run under "not runserver". A common companion use case: dump the full diagnostics only when a server starts up, while keeping management command startups quiet.

A typical pattern in settings.py:

show_settings = "show_settings" in sys.argv

if DEBUG and RUN_CONTEXT not in ("runserver_reloader", "not runserver") or show_settings:
    import django
    import sys

    log.debug("SETTINGS LOADED (in context '%s'):", RUN_CONTEXT)
    log.debug("Python version: %s", sys.version)
    log.debug("Python executable: %s", sys.executable)
    log.debug("Using path: %s", sys.path)
    log.debug("Django version: %s", django.__version__)
    log.debug("Django loaded from: %s", django.__file__)
    log.debug("Installed apps: %s", INSTALLED_APPS)
    log.debug("Database: %s", DATABASES["default"])
    log.debug("Command line: %s", sys.argv)

Here RUN_CONTEXT not in ("runserver_reloader", "not runserver") means the dump is emitted:

• in the actual runserver webserver process ("runserver_reloaded" / "runserver_noreloader"), not in the supervising reloader, so it appears only once; and
• not in management commands, so they start clean.

Passing show_settings as an argument to any management command forces the dump regardless of context:

python manage.py shell show_settings
python manage.py some_command show_settings

How it works

Django's autoreloader marks the spawned server process with the environment variable RUN_MAIN (exposed as the private constant django.utils.autoreload.DJANGO_AUTORELOAD_ENV) set to "true". This module combines that flag with the presence of runserver and --noreload in sys.argv to classify the current process.

Compatibility

• Python 3.7+
• Django 2.2+

License

Hippocratic License 3.0