Allow reading from environment variables in configuration file

[poperigby]

This would be useful for reading secrets in the configuration file. Environment variables could be written like this:

key: {{VARIABLE}}

[pbiering]

This would be useful for reading secrets in the configuration file. Environment variables could be written like this:

key: {{VARIABLE}}

this is not a format of a Windows or Linux environment option...it must be something like that

RADICALE_OPTION__<section>__<key>="<value>"

and order should be config file -> environment -> command line

Contribution is required

[pbiering]

this is not a format of a Windows or Linux environment option...it must be something like that

I was talking about having the environment variable directly in the config file, but that would work too.

Hmm, also an option.

I could take a crack at it. Do you mind pointing me in the right direction?

radicale/config.py would require an extension.

[poperigby]

Thanks. What would be your preference? In the config file, or not?

[pbiering]

Thanks. What would be your preference? In the config file, or not?

I would prefer having support without tweaking the config file, so imply lookup environment, search for entries matching the pattern

RADICALE_OPTION__<section>__<key>

validate <value> and then override the internal one provided by config file and/or command line option, I would also prefer having this logged on info level.

[poperigby]

Sounds good. Where should I put this environment variable handling in config.py?

[pbiering]

I would assume the update function must be somehow extended or cloned+adjusted...as it is called currently by __main__.py

   try:
        configuration = config.load(config.parse_compound_paths(
            config.DEFAULT_CONFIG_PATH,
            os.environ.get("RADICALE_CONFIG"),
            os.pathsep.join(args_ns.config) if args_ns.config is not None
            else None))
        if arguments_config:
            configuration.update(arguments_config, "command line arguments")
    except Exception as e:
        logger.critical("Invalid configuration: %s", e, exc_info=True)
        sys.exit(1)

Before if arguments_config the environment based configuration should be called imho.

[pbiering]

Draft: #1577