golang webserver listening on a random port

webserver_random_port.go

package main

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

func indexHandler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprint(w, "foobar\n")
}

func main() {
    listener, err := net.Listen("tcp", "127.0.0.1:0")
    if err != nil {
        panic(err)
    }
    log.Printf("listening on: %s", listener.Addr().String())
    http.HandleFunc("/", indexHandler)
    panic(http.Serve(listener, nil))
}