mux2

A http router (mux) with the simplicity of net/http's ServeMux, but adds:

• Parameters

m.Handle("/:userID/info", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
	userID := mux2.Param(r, "userID")
}))

// You can use parameters and static routes together:
m.Handle("/user/me", meHandler)
m.Handle("/user/:userID", userHandler)

• HTTP method matching:

m.Handle("/allMethods", h)
m.Put("/path", h)
m.Get("/path", h)

• Stacked middleware

m.Get("/public", publicGET)
m.Push(WithUser)
m.Get("/me", meGET)
m.Get("/me/avatar", meAvatarGET)

// or:
m.Get("/admin", adminGET, WithUser, WithAdmin)

• Declare routes in var init

var apiHandler = mux2.NewFromFunc(func(m *mux2.Mux) {
	m.Get("/me", meGET)
})

Implementation & performance

The implementation is simple: requests are routed using a sorted slice of mux entries.

• Static routing is fast and simple: a binary search in a contiguous slice.
• Dynamic routing can still use the sorted slice to prune a lot of the search space, especially for common use cases.
• Unintuitively, it uses roughly half the memory as implementations that use radix tries.
• There are no heap allocations per request, except those incurred by request.WithContext(). That call alone incurs a 5x performance hit for dynamic routes, though. I don't see a way to prevent this while sticking to the http.Handler interface.
• No dependencies.

All in all, compared to the very fast httprouter:

• static routing performs similar
• dynamic routing is roughly 5x slower (httprouter's has its own Handler type)
• memory usage is around half
• approximately 5x less code

(tests based on go-http-routing-benchmark.)

TODO

• Add documentation in code, publish godoc
• More tests
• Import benchmarks to this repository: is there a way to do it without depending on httprouter?
• Perhaps: redir "/x" => "/x/" when the former is not defined, but latter is
• Perhaps: 405 method not supported when handler with other method matches
• Perhaps: multi-goroutine safe registration (like net/http.ServeMux)
• Perhaps: host name based matching (like net/http.ServeMux)