Configuration (.env)

The application is configured with environment variables from the .env file in the project root. Templates are in the repository:

• .env.docker.example for Docker,
• .env.example for a local installation.

After changing .env, restart the application (docker compose up -d, or restart the server).

Django and security

Variable	Default	Description
SECRET_KEY	(insecure default)	Required. A long random string, never share it.
DEBUG	False	Always False in production.
ALLOWED_HOSTS	127.0.0.1,localhost	Comma-separated domains and IP addresses the app responds on. Locally, add the computer's IP so you can scan from a phone.
CSRF_TRUSTED_ORIGINS	(empty)	Full origins including the scheme, e.g. https://odbavto.example.com. Required behind an HTTPS proxy.
BEHIND_PROXY	False	True behind a reverse proxy that terminates TLS. Hard-coded in docker-compose.yml.
SECURE_SSL_REDIRECT	False	HTTP → HTTPS redirect in Django. Not needed behind Caddy, which redirects itself.
SESSION_COOKIE_SECURE	False	True = session cookie over HTTPS only. Turn on in production.
CSRF_COOKIE_SECURE	False	True = CSRF cookie over HTTPS only. Turn on in production.
RATELIMIT_ENABLE	True	Request rate limiting (scan 60/min, import 10/h per IP).

HTTPS is an operational requirement

The hostess access link and the login session must go over HTTPS. On a server, set SESSION_COOKIE_SECURE=True and CSRF_COOKIE_SECURE=True. These options only apply with DEBUG=False.

Database

Variable	Default	Description
DATABASE_URL	(empty = SQLite)	E.g. postgres://user:password@db:5432/odbavto. In Docker it is built automatically from DB_*.
DB_NAME, DB_USER, DB_PASSWORD		Docker only: credentials for the PostgreSQL container.
CREATE_DEFAULT_USER	True without DATABASE_URL, otherwise False	Creates the user odbavto / odbavto on an empty database.

Docker

Variable	Description
COMPOSE_PROJECT_NAME	Project name. Determines the container name (<name>-web) and the volume prefix. Lets you run several instances on one server (e.g. odbavto and odbavto-staging).

Language and logging

Variable	Default	Description
LANGUAGE_CODE	cs	Default interface language: cs or en. Users can switch it.
LOG_LEVEL	INFO	DEBUG, INFO, WARNING, ERROR.

The time zone is fixed to Europe/Prague.

Printing and WebSockets

Variable	Default	Description
ENABLE_DIRECT_PRINTING	False	Enables the Direct print backend (printing from the server through the Windows driver). Local Windows installation only.
REDIS_HOST	127.0.0.1	Redis for WebSockets. In Docker redis.
REDIS_PORT	6379
REDIS_SOCKET_TIMEOUT	30	Must be more than 5 s, otherwise WebSockets drop every ~5 s.
PENDING_JOB_MAX_AGE_SECONDS	300	Older unclaimed print jobs are discarded so that old badges don't print when the agent comes back online.