Configuration

Copper provides the cconfig package that helps read hierarchical TOML files into simple Go structs. The TOML config files live in the ./config directory with a few out-of-the-box files such as base.toml, dev.toml, and prod.toml.

You are encouraged to extend and customize the structure of the ./config directory as needed for your project.

Extensible TOML Files

The configurations are defined in simple TOML files that support a special extends key:

config/dev.toml

extends = ["base.toml"]

[starship]
destination = "HD1"
use_wormholes = false

In the example above, the dev.toml file defines a top-level extends key which is set to base.toml. As a result, any project that is run with the dev.toml config file will inherit all configuration values from base.toml.

Do not use top-level configuration values. Remember to group all values under a section so they can be loaded per package without needing a "global" app config.

Read Configuration

You can read a config section using cconfig.Loader#Load. The values are loaded into a destination Go struct. The config loader accounts for the hierarchy of all TOML files that use extends.

pkg/starship/config.go

package starship

import (..)

func LoadConfig(configs cconfig.Loader) (Config, error) {
	var config Config

	err := configs.Load("starship", &config)
	if err != nil {
		return Config{}, cerrors.New(err, "failed to load starship config", nil)
	}

	return config, nil
}

type Config struct {
	Destination  string `toml:"destination"`
	UseWormholes bool   `toml:"use_wormholes"`
}