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XDG::GuaranteedResources zef:masukomi last updated on 2022-10-16

3aae42602421c348e31447a0aa9dd6f488cb7137/

NAME

XDG::GuaranteedResources - Guarantees that a resource is present in the expected XDG Base Directory directory

SYNOPSIS

First, you need to implement a class that can get resources from within your package. I suggest you copy this, and change the class name. Alas, this is not something that another package like this one can provide.

use XDG::GuaranteedResources::AbstractResourcer;

unit class My::Resourcer does XDG::GuaranteedResources::AbstractResourcer;

# for XDG::GuaranteedResources::AbstractResourcer
method fetch-resource(::?CLASS:U:){%?RESOURCES;}

Once you've got that, you can just pass it in as the 2nd param to either of the provided methods, or assign it to a variable and pass that in.

use XDG::GuaranteedResources;
# pass it the relative path to a file under your resources directory
# path must be listed in the resources array of your META6.json
guarantee-resource("config/my_app/app_config.toml", My::Resourcer);

# assigning your resourcer to a variable is fine.
my $resourcer = My::Resourcer;
# if you have multiple to guarantee you pass a list to the plural form.
guarantee-resources(<config/my_app/app_config.toml data/my_app/cool_database.db>, $resourcer);

DESCRIPTION

Many tools expect a config file, sqlite database, or similar to be present. We store these in the resources listed in META6.json, and need to test if they exist and copy them over from resources if not.

XDG::GuaranteedResources handles this common operation.

For example:

Let's assume your script uses a pre-prepared sqlite db that you store under resources. Store it under resources/data/my_app/my_database.db, then when your script boots up you can call guarantee-resource("data/my_app/my_database.db");. If that file already exists under %*ENV<XDG_CONFIG_HOME>/my_app/my_database.db nothing will happen. If it isn't found there, a fresh copy will be placed there from the one you referenced in resources.

Note that my_app should be the directory name your apps files should be stored under. For example, a config file for clu would be stored under ~/.config/clu/ after install. So, you would store it under resources/config/clu/ in your package.

Resources that should be copied to XDG_CONFIG_HOME should be stored under resources/config/my_app

Resources that should be copied to XDG_DATA_HOME should be stored under resources/data/my_app

Subdirectories are fine. E.g. resources/data/my_app/subdir/my_db.db

⚠ Currently only works on Unix (Linux, BSD, macOS, etc.) systems.

AUTHOR

Kay Rhodes a.k.a masukomi ([email protected])

COPYRIGHT AND LICENSE

Copyright 2022

This library is free software; you can redistribute it and/or modify it under the MIT License.

multi sub guarantee-resource

multi sub guarantee-resource(
    Str $resource_path,
    $resourcer
) returns Str

Guarantees a resource is present & provides the path it can be found at.

sub guarantee-resources

sub guarantee-resources(
    @resource_paths,
    $resourcer
) returns Array

Guarantees a list of resources are present. Returns the paths they can be found at.