feat: add config loader

internal/config/config.go

@@ -0,0 +1,74 @@
+package config
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/joho/godotenv"
+)
+
+type Config interface {
+	Addr() string
+	Port() string
+	DatabaseURL() string
+}
+type config struct {
+	addr        string
+	port        string
+	databaseURL string
+}
+
+func (c *config) Addr() string {
+	return c.addr
+}
+
+func (c *config) Port() string {
+	return c.port
+}
+
+func (c *config) DatabaseURL() string {
+	return c.databaseURL
+}
+
+func parse() (*config, error) {
+	domain := getenv("ADDRESS", "0.0.0.0")
+	sshPort := getenv("PORT", "8080")
+	databaseURL := getenv("DATABASE_URL", "")
+
+	if databaseURL == "" {
+		return nil, fmt.Errorf("DATABASE_URL environment variable not set")
+	}
+
+	return &config{
+		addr:        domain,
+		port:        sshPort,
+		databaseURL: databaseURL,
+	}, nil
+}
+
+func loadEnvFile() error {
+	if _, err := os.Stat(".env"); err == nil {
+		return godotenv.Load(".env")
+	}
+	return nil
+}
+
+func getenv(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}
+
+func MustLoad() (Config, error) {
+	if err := loadEnvFile(); err != nil {
+		return nil, err
+	}
+
+	cfg, err := parse()
+	if err != nil {
+		return nil, err
+	}
+
+	return cfg, nil
+}