regexp route nested wrongly -> no routing

[mvrhov]

I've been scratching my head for the past day where the chi wouldn't route the request properly. Here are the registered routes.

r.Route("/accounts/{id:(me|[a-zA-Z0-9]{10,})})", func(r chi.Router) {
//works
})
r.Route("/accounts/{id:(me|[a-zA-Z0-9]{10,})})/new_link", func(r chi.Router) {
//works
})
r.Route("/accounts/{id:(me|[0-9]+)}/Backward_compat_link, func(r chi.Router) {
//no request won't be routed here debugger shows that this route has been added under /accounts/{id:(me|[a-zA-Z0-9]{10,})})
})

[FelipeRenault]

Apparently, if you make a different regex, but it matches the other, it returns a 404. I had this example:

r.Get("/one/{firstId:[a-z0-9-]+}/{secondId:[a-z0-9-]+}/type.json", handler)
r.Get("/one/{firstId:[a-z0-9-_]+}/{secondId:[a-z0-9-_]+}.json", secondHandler}

I could access the first path, but not the second.

[rodrigo-brito]

Same problem here! 😞

[AlisonOSouza]

The same happen in here.

In this example, get routes works but delete returns 405 (not allowed):

r.Route("/one", func(r chi.Router) {
	r.Get("/{dns:[a-z-0-9_]+}", getHandler)
	r.Get("/{dns:[a-z-0-9_]+}/info", infoHandle)
	...
	r.Delete("/{id:[0-9]+}", deleteHandler)
})

if I remove the first get route, then delete returns 404 (route not found), like Felipe said:

r.Route("/one", func(r chi.Router) {
//	r.Get("/{dns:[a-z-0-9_]+}", getHandler)
	r.Get("/{dns:[a-z-0-9_]+}/info", infoHandle)
	...
	r.Delete("/{id:[0-9]+}", deleteHandler)
})

And in this, all routes works:

r.Route("/one", func(r chi.Router) {
	r.Get("/{dns:[a-z-0-9_]+}", getHandler)
	r.Get("/{dns:[a-z-0-9_]+}/info", infoHandle)
	...
})
r.Delete("/one/{id:[0-9]+}", deleteHandler)

🤷‍♂️

[mohamedfar97]

I think that’s because the Route struct is composed of one pattern string and a map of handlers.
Better option is to create a new router and mount it over the desired path
Note: try use the reset context method in the documentation to reset the route context after each request

[mohamedfar97]

Try putting /*/ before each request pattern

[pkieltyka]

hey all, I've found the bug for this issue. The issue is in the findRoute method where for a regexp search, it fails to recursively try all paths until it finds the terminal/final handler.

func TestMuxRegexp4(t *testing.T) {
	r := NewRouter()
	r.Get("/one/{firstId:[a-z0-9-]+}/{secondId:[a-z]+}/first", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("first"))
	})
	r.Get("/one/{firstId:[a-z0-9-_]+}/{secondId:[0-9]+}/second", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("second"))
	})

	ts := httptest.NewServer(r)
	defer ts.Close()

	if _, body := testRequest(t, ts, "GET", "/one/hello/peter/first", nil); body != "first" {
		t.Fatalf(body)
	}
	if _, body := testRequest(t, ts, "GET", "/one/hithere/123/second", nil); body != "second" {
		t.Fatalf(body)
	}
}

here is a test case that should pass but in fact is not. The reason for it is that the GET /one/hithere/123/second request will match the first routing pattern as "hithere" segment matches the {firstId:[a-z0-9-]+} param, then as it tests the second param {secondId:[a-z]+}, this will of course not match the 123 value in the request, as a result returning a 404. What this should be doing though is a recursive search to the second route, attempting each permutation. This is how the rest of the chi tree walking algorithm works, but I've noticed here https://github.com/go-chi/chi/blob/master/tree.go#L414-L454 needs to be revised to be a recursive.

just FYI in case someone wants to take a stab at it

[pkieltyka]

thanks to @Jahaja 's PR, this is now solved in master