Development notes

This section will provide some useful hints and tips for developing Argus.

Applying settings and switching between them

As elaborated in Site-specific settings, there are two ways to define settings in Argus:

1. with environment variables

2. using a settings.py file.

For development, a simple and good practice is to define environment variables in a cmd.sh file. This file serves as a “wrapper” to call manage.py with a defined set of environment variables, and simplifies the development process.

You may find it useful to have several cmd.sh files for different purposes, for instance to invoke different databases. The files can be named cmd-local.sh, cmd-prod.sh and cmd-demo.sh or similar.

The limitation of environment variables is that they can only contain numbers, Boolean values (0/1) and strings. Use the localsettings.py file to define settings that require more complex values, such as conditional expressions, Python dicts and tuples.

Settings in the settings.py file will override environment variables. Note that the extra settings-file and argus have to be in the python path. We therefore recommend keeping your settings.py files in the same directory as manage.py.

Settings can be tested in localsettings.py and moved to the other settings files later.

Note

Tip: If you copy the entire logging-setup from “argus.site.settings.dev” to localsettings.py remember to set disable_existing_loggers to True. Otherwise, logentries will appear twice.

Warning

Do not check your cmd.sh or settings.py files into version control, since they contain passwords and sensitive data.