feat: add env loading

internal/config/config.go

@@ -1,8 +1,81 @@
 package config
 
-import "os"
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"errors"
+	"log"
+	"os"
 
-func Getenv(key, defaultValue string) string {
+	"github.com/joho/godotenv"
+)
+
+type config struct {
+	databaseUrl    string
+	controllerAddr string
+	apiAddr        string
+	authToken      string
+	jwksUrl        string
+}
+
+type Config interface {
+	DatabaseURL() string
+	ControllerAddr() string
+	ApiAddr() string
+	AuthToken() string
+	JwksURL() string
+}
+
+func (c *config) DatabaseURL() string    { return c.databaseUrl }
+func (c *config) ControllerAddr() string { return c.controllerAddr }
+func (c *config) ApiAddr() string        { return c.apiAddr }
+func (c *config) AuthToken() string      { return c.authToken }
+func (c *config) JwksURL() string        { return c.jwksUrl }
+
+func MustLoad() (Config, error) {
+	if err := loadEnvFile(); err != nil {
+		return nil, err
+	}
+
+	cfg, err := parse()
+	if err != nil {
+		return nil, err
+	}
+
+	return cfg, nil
+}
+
+func loadEnvFile() error {
+	if _, err := os.Stat(".env"); err == nil {
+		return godotenv.Load(".env")
+	}
+	return nil
+}
+
+func parse() (*config, error) {
+	databaseUrl := getenv("DATABASE_URL", "")
+	if databaseUrl == "" {
+		return nil, errors.New("DATABASE_URL environment variable not set")
+	}
+	controllerAddr := getenv("CONTROLLER_ADDR", ":8080")
+	apiAddr := getenv("API_ADDR", ":8081")
+	authToken := getenv("AUTH_TOKEN", "")
+	if authToken == "" {
+		authToken = generateAuthToken()
+		log.Printf("No AUTH_TOKEN provided. Generated token: %s", authToken)
+	}
+	jwksUrl := getenv("JWKS_URL", "")
+
+	return &config{
+		databaseUrl:    databaseUrl,
+		controllerAddr: controllerAddr,
+		apiAddr:        apiAddr,
+		authToken:      authToken,
+		jwksUrl:        jwksUrl,
+	}, nil
+}
+
+func getenv(key, defaultValue string) string {
 	val := os.Getenv(key)
 	if val == "" {
 		val = defaultValue
@@ -10,3 +83,11 @@ func Getenv(key, defaultValue string) string {
 
 	return val
 }
+
+func generateAuthToken() string {
+	buf := make([]byte, 32)
+	if _, err := rand.Read(buf); err != nil {
+		panic(err)
+	}
+	return base64.StdEncoding.EncodeToString(buf)
+}