// GetPathRelativeToConfig gets a configuration key which is a path, and if
// it is not empty or an absolute path, returns the absolute path relative
// to the configuration file
func GetPathRelativeToConfig(configuration *viper.Viper, key string) string {
configFile := configuration.ConfigFileUsed()
p := configuration.GetString(key)
if p == "" || filepath.IsAbs(p) {
return p
}
return filepath.Clean(filepath.Join(filepath.Dir(configFile), p))
}