configuration.go

const (
	// Constants for viper variable names. Will be used to set
	// default values as well as to get each value
	...
	varLogLevel                     = "log.level"
)

func New() *Configuration {
	c := Configuration{
		v: viper.New(),
	}
	...
	c.v.SetDefault(varPathToConfig, "./config.yaml")
	c.v.SetDefault(varLogLevel, "info")
	c.v.AutomaticEnv()
	c.v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
	c.v.SetTypeByDefaultValue(true)
	c.v.SetConfigFile(c.GetPathToConfig())
	err := c.v.ReadInConfig() // Find and read the config file
	logrus.WithField("path", c.GetPathToConfig()).Warn("loading config")
	// just use the default value(s) if the config file was not found
	if _, ok := err.(*os.PathError); ok {
		logrus.Warnf("no config file '%s' not found. Using default values", c.GetPathToConfig())
	} else if err != nil { // Handle other errors that occurred while reading the config file
		panic(fmt.Errorf("fatal error while reading the config file: %s", err))
	}
	setLogLevel(c.GetLogLevel())
	// monitor the changes in the config file
	c.v.WatchConfig()
	c.v.OnConfigChange(func(e fsnotify.Event) {
		logrus.WithField("file", e.Name).Warn("Config file changed")
		setLogLevel(c.GetLogLevel())
	})
	return &c
}

// GetLogLevel returns the log level
func (c *Configuration) GetLogLevel() string {
	return c.v.GetString(varLogLevel)
}

...

hi can you give us please a little more context or a complete example
who is supposed to get Configuration instantiated with New()*Configuration

Sorry, I mean, how can I access my configuration from my cobra Command for instance
That is the example I am definitely looking forward to find.

EDIT

most of the answers can easily be found at https://github.com/spf13/viper

ReadInConfig makes the configuration available simply with calling New(). This is that simple. After-all, all the getters are available to the interface you design (here it is Configuration).

Also there is much more viper can do dealing with key/value stores (encrypted and unencrypted). For example
https://github.com/spf13/viper#remote-keyvalue-store-example---encrypted