add auth lib

token/token.go

@@ -0,0 +1,25 @@
+package token
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"fmt"
+)
+
+func GenerateURLSafe(size int) (string, error) {
+	if size <= 0 {
+		return "", fmt.Errorf("token size must be positive")
+	}
+	raw := make([]byte, size)
+	if _, err := rand.Read(raw); err != nil {
+		return "", fmt.Errorf("generate secure token: %w", err)
+	}
+	return base64.RawURLEncoding.EncodeToString(raw), nil
+}
+
+func HashSHA256(value string) string {
+	sum := sha256.Sum256([]byte(value))
+	return hex.EncodeToString(sum[:])
+}