config.go

config.go

//NewConfigFromFile function loads a YAML file and returns
//a pointer to a newly create Configuration struct
func NewConfigFromFile(path string) (*Config, error) {
	cfg := New(Config)

	if _, err := os.Stat(path); os.IsNotExist(err) {
		return nil, errors.New("Cannot open configuration file")
	}

	readed, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, errors.New("Cannot read configuration file")
	}

	config := make(map[interface{}]interface{})

	err = goyaml.Unmarshal(readed, &m)

	if err != nil {
		return nil, errors.New(fmt.Sprintf("error: %v", err))
	}

	for _, required := range []string{"services", "levels"} {
		_, ok := config[required]
		if !ok {
			return nil, errors.New(fmt.Sprintf(
				"configuration key(%s) not found", required))
		}
	}

	servicesFiles, err := filepath.Glob(config["services"])
	if err != nil {
		return nil, errors.New("cannot find any defined services")
	}

	for _, serviceFile := range servicesFiles {
		service, err := core.NewServiceFromFile(serviceFile)
		if err != nil {
			return nil, err
		}
		cfg.services = append(cfg.services, &service)
	}

	for _, level := range config["levels"] {
		level, err := core.NewLevel(level)
		if err != nil {
			return nil, err
		}
		cfg.levels = append(cfg.levels, &level)
	}

	return &cfg, nil
}