mux-middle.go

package main

import (
    "fmt"
    "github.com/gorilla/mux"
    "net"
    "net/http"
)

func returnFj(w http.ResponseWriter, r *http.Request) {
    fj := `{"VERSION":1.0, "ep-db" : "", "interfaces" : "" }`
    w.WriteHeader(201)
    if _, e := w.Write([]byte(fj)); e != nil {
        panic(e)
    }
}

type statusRecorder struct {
    http.ResponseWriter
    status int
}

func (rec *statusRecorder) WriteHeader(code int) {
    rec.status = code
}

func Middleware(h http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        rec := statusRecorder{w, 0}
        h.ServeHTTP(&rec, r)
        if rec.status == http.StatusMovedPermanently {
            fmt.Println("Fixing 301 -> 308")
            w.WriteHeader(http.StatusPermanentRedirect)
        }
    })
}

func main() {
    rtr := mux.NewRouter()
    rtr.Handle("/cc/fj", http.HandlerFunc(returnFj)).Methods("POST")
    l, _ := net.Listen("tcp", "localhost:11225")
    http.Serve(l, Middleware(rtr))
}