🐛 [Bug]: The correct path cannot be obtained from the middleware.

[KScaesar]

Bug Description

Currently, I'm working on observability (o11y) and need to metric the current API path to track API performance.

In Prometheus' recommendations, it's mentioned that labels should ideally have a static string;
if labels are dynamic, performance may degrade.

However, when I use fiber middleware, I'm unable to obtain the expected path.
When I use c.Route().Path, I expect to get /users/:id, but I keep getting /.
When I use c.Path(), I can get the correct path /users/123, but it doesn't meet Prometheus' requirement for static labels.

How to Reproduce

Steps to reproduce the behavior:

1. setup middleware and get c.Route().Path

Expected Behavior

expected path should be /users/:id

Fiber Version

v2.52.5

Code Snippet (optional)

router := fiber.New()

prometheusMiddleware := func(c *fiber.Ctx) error {
	path1 := c.Path()
	path2 := c.Route().Path
	log.Printf("path1=%v path2=%v in prometheus middleware\n", path1, path2)
	return c.Next()
}
router.Use(prometheusMiddleware)

userHandler := func(c *fiber.Ctx) error {
	path1 := c.Path()
	path2 := c.Route().Path
	log.Printf("path1=%v path2=%v in user handler\n", path1, path2)
	return c.SendString("User ID: " + c.Params("id"))
}
router.Get("/users/:id", userHandler)

req := httptest.NewRequest(http.MethodGet, "/users/123", nil)
router.Test(req)

// 2024/09/18 14:42:27 path1=/users/123 path2=/          in prometheus middleware
// 2024/09/18 14:42:27 path1=/users/123 path2=/users/:id in user handler

playground

Checklist:

• I agree to follow Fiber's Code of Conduct.
• I have checked for existing issues that describe my problem prior to opening this one.
• I understand that improperly formatted bug reports may be closed without explanation.

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[ReneWerner87]

for this we are working on a new middleware
gofiber/contrib#1032

the behavior you see during routing is normal

because the route of the middleware itself is the “root”
this is also how it works in expressjs

@gaby what was the development status?

[Noraddeen]

I used this and worked
router.Get("/users/:id",prometheusMiddleware, userHandler)