如何在 Go 中的中間件和處理程序之間共享資料？

import (
    "context"
    "github.com/gorilla/mux"
)

func Middleware(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // Middleware operations
        // Parse body/get token.
        token := parseToken(r)
        ctx := context.WithValue(r.Context(), "token", token)

        next.ServeHTTP(w, r.WithContext(ctx))
    })
}

func Handler() http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        token := r.Context().Value("token")
        // Continue with handler logic
    })
}