How can I better handle config files?

Question

In a package I'm writing, I have a config module that looks like this:

use v6.d;
use JSON::Fast;
use PSBot::Tools;

sub EXPORT(--> Hash) {
    my Str $path = do if %*ENV<TESTING> {
        $*REPO.Str.IO.child('META6.json').e
            ?? $*REPO.Str.IO.child('t/config.json').Str         # For when testing using zef
            !! $*REPO.Str.IO.parent.child('t/config.json').Str; # For when testing using prove
    } elsif $*DISTRO.is-win {
        "%*ENV<LOCALAPPDATA>\\PSBot\\config.json"
    } else {
        "$*HOME/.config/PSBot/config.json"
    };

    unless $path.IO.e {
        note "PSBot config at $path does not exist!";
        note "Copy psbot.json.example there and read the README for instructions on how to set up the config file.";
        exit 1;
    }

    with from-json slurp $path -> %config {
        %(
            USERNAME               => %config<username>,
            PASSWORD               => %config<password>,
            AVATAR                 => %config<avatar>,
            HOST                   => %config<host>,
            PORT                   => %config<port>,
            SERVERID               => %config<serverid>,
            COMMAND                => %config<command>,
            ROOMS                  => set(%config<rooms>.map: &to-roomid),
            ADMINS                 => set(%config<admins>.map: &to-id),
            MAX_RECONNECT_ATTEMPTS => %config<max_reconnect_attempts>,
            GIT                    => %config<git>,
            DICTIONARY_API_ID      => %config<dictionary_api_id>,
            DICTIONARY_API_KEY     => %config<dictionary_api_key>,
            YOUTUBE_API_KEY        => %config<youtube_api_key>,
            TRANSLATE_API_KEY      => %config<translate_api_key>
        )
    }
}

Every time I make changes to the config file, I have to delete the precomp files for the changes to appear. Is there a way I can write this so the exports aren't defined at compile time so users don't have to do this?

Answer 1

Assuming I understand your intentions correctly, one way to do it would be this:

1. get rid of the EXPORT sub
2. place the computation of $path and %config into the module's mainline

3. declare your 'constants' as terms such as

   sub term:<USERNAME> is export { %config<username> }