major refactor of main.go

config/config.go

@@ -0,0 +1,36 @@
+package config
+
+import (
+	"log"
+	"os"
+)
+
+type Config struct {
+	APIKey      string
+	DefaultCity string
+	DBHost      string
+	DBPort      string
+	DBUser      string
+	DBPassword  string
+	DBName      string
+}
+
+func GetEnv(key string) string {
+	val := os.Getenv(key)
+	if val == "" {
+		log.Fatalf("missing required env var: %s", key)
+	}
+	return val
+}
+
+func Load() *Config {
+	return &Config{
+		APIKey:      GetEnv("OPENWEATHERMAP_API_KEY"),
+		DefaultCity: GetEnv("WEATHER_CITY"),
+		DBHost:      GetEnv("DB_HOST"),
+		DBPort:      GetEnv("DB_PORT"),
+		DBUser:      GetEnv("DB_USER"),
+		DBPassword:  GetEnv("DB_PASSWORD"),
+		DBName:      GetEnv("DB_NAME"),
+	}
+}