WeatherService/src/config/Configuration.go

package config

import (
	"fmt"
	"os"
	"strconv"
	"strings"
)

type Configuration struct {
	ApiKey   string
	Language string
	Units    Units

	Port      int
	JwtSecret string

	SentryDsn string
}

func (config Configuration) String() string {
	return fmt.Sprintf("api_key=%s language=%s, units=%s, port=%d, jwt_secret=%s", config.ApiKey, config.Language, config.Units, config.Port, config.JwtSecret)
}

//returns a new Config struct
func LoadConfiguration() *Configuration {
	return &Configuration{
		ApiKey:    getEnv("API_KEY", ""),
		Language:  getEnv("LANGUAGE", "en"),
		Units:     StringToUnit(getEnv("UNITS", "metric")),
		Port:      getEnvAsInt("PORT", 8080),
		JwtSecret: getEnv("JWT_SECRET", "super secret value"),
		SentryDsn: getEnv("SENTRY_DSN", ""),
	}
}

// Simple helper function to read an environment or return a default value
func getEnv(key string, defaultVal string) string {
	if value, exists := os.LookupEnv(key); exists {
		return value
	}

	return defaultVal
}

// Simple helper function to read an environment variable into integer or return a default value
func getEnvAsInt(name string, defaultVal int) int {
	valueStr := getEnv(name, "")
	if value, err := strconv.Atoi(valueStr); err == nil {
		return value
	}

	return defaultVal
}

type Units int

const (
	Metric Units = iota
	Imperial
)

func (unit Units) String() string {
	return [...]string{"metric", "imperial"}[unit]
}

func StringToUnit(string string) Units {

	if strings.EqualFold(string, "metric") {
		return Metric
	} else {
		return Imperial
	}
}