Go: How to use middleware pattern?

I have a function that executes only with specific conditions (e.g. <i>role == 'Administrator'</i>). Now, I use <i>'if'</i> statement. But it could be situations when number of conditions is high and <i>'if'</i> with long definition looks not so esthetic.<br>
Is it available mechanism in Go (or related with Go framework) allows implementation of middleware <b>concept</b> (action filters)?<br><br>
<i>For example, ASP.NET MVC allows to do this:</i>

[MyFilter]
public ViewResult Index()
{
     // Filter will be applied to this specific action method
}

<i>So, MyFilter() implemented in the separate class allows better code composition and testing.</i><br>

<b>Update:</b>
Revel (web framework for the Go) provides similar functionality with
Interceptors (function that is invoked by the framework BEFORE or AFTER an action invocation): https://revel.github.io/manual/interceptors.html

This sort of thing is typically done with middleware in Go. The easiest is to show by example:

package main

import (
    "fmt"
    "html"
    "log"
    "net/http"
)

func main() {
    http.HandleFunc("/", handler)
    http.HandleFunc("/foo", middleware(handler))

    log.Fatal(http.ListenAndServe(":8080", nil))
}

func handler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path))
}

func middleware(next http.HandlerFunc) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        r.URL.Path = "/MODIFIED"

        // Run the next handler
        next.ServeHTTP(w, r)
    }
}

As you can see, a middleware is a function that:

1. accepts a http.HandlerFunc as an argument;
2. returns a http.HandlerFunc;
3. calls the http.handlerFunc passed in.

With this basic technique you can "chain" as many middlewares as you like:

http.HandleFunc("/foo", another(middleware(handler)))

There are some variants to this pattern, and most Go frameworks use a slightly different syntax, but the concept is typically the same.

Revel (web framework for the Go) provides similar functionality with<br>
<b>Interceptors</b> (function that is invoked by the framework BEFORE or AFTER an action invocation).<br>
Concept and implementation described here: https://revel.github.io/manual/interceptors.html