add authentication for kontor-api-go

kontor-api-go/pkg/handler/auth.go

@@ -0,0 +1,43 @@
+package handler
+
+import (
+	"time"
+
+	"github.com/gofiber/fiber/v2"
+	"github.com/golang-jwt/jwt/v5"
+)
+
+func Login(c *fiber.Ctx) error {
+	user := c.FormValue("user")
+	pass := c.FormValue("pass")
+
+	// Throws Unauthorized error
+	if user != "john" || pass != "doe" {
+		return c.SendStatus(fiber.StatusUnauthorized)
+	}
+
+	// Create the Claims
+	claims := jwt.MapClaims{
+		"name":  "John Doe",
+		"admin": true,
+		"exp":   time.Now().Add(time.Hour * 72).Unix(),
+	}
+
+	// Create token
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+
+	// Generate encoded token and send it as response.
+	t, err := token.SignedString([]byte("secret"))
+	if err != nil {
+		return c.SendStatus(fiber.StatusInternalServerError)
+	}
+
+	return c.JSON(fiber.Map{"token": t})
+}
+
+func Restricted(c *fiber.Ctx) error {
+	user := c.Locals("user").(*jwt.Token)
+	claims := user.Claims.(jwt.MapClaims)
+	name := claims["name"].(string)
+	return c.SendString("Welcome " + name)
+}