setup.go

package logrusutil

import (
	"errors"
	"io/ioutil"
	"sync"

	"github.com/sirupsen/logrus"
)

var (
	// ErrLevelNotProvided is returned when a level was not provided
	// in the config struct.
	ErrLevelNotProvided = errors.New("level not provided")

	mtx = &sync.Mutex{}
)

// ConfigureLogger will use the provided configuration to setup the root
// logrus logger.
func ConfigureLogger(logger *logrus.Logger, config *Config) error {
	// Not all of the below operations are thread safe in logrus.
	mtx.Lock()
	defer mtx.Unlock()

	if config.Level == "" || config.HookLevel == "" {
		return ErrLevelNotProvided
	}

	if config.Level == DisabledLevel {
		logger.Out = ioutil.Discard

		// We set the level to panic here because even though we're
		// discarding output logrus will still log.
		logger.SetLevel(logrus.PanicLevel)
	}

	if config.Level != DisabledLevel {
		// Setup the logger's root level.
		level, err := logrus.ParseLevel(config.Level)
		if err != nil {
			return err
		}
		logger.SetLevel(level)
	}

	if config.HookLevel != DisabledLevel {
		level, err := logrus.ParseLevel(config.HookLevel)
		if err != nil {
			return err
		}
		logger.Hooks.Add(
			NewCallerHook(
				false, config.HookStackLevel,
				config.CallerHookField, level))
		return nil
	}

	return nil
}