go get gitlab.schukai.com/oss/libraries/go/network/http-negotiation

package main

import (
	"net/http"
	"gitlab.schukai.com/oss/libraries/go/network/http-negotiation"
)

func handleRequest(w http.ResponseWriter, r *http.Request) {
	n := negotiation.New(r.Header)

	if n.Type("application/json") == "application/json" {
		w.Header().Set("Content-Type", "application/json")
		w.Write([]byte(`{"message": "Hello World!"}`))
		return
	}

}

package main

import (
	"net/http"
	"gitlab.schukai.com/oss/libraries/go/network/http-negotiation"
)

func handleRequest(w http.ResponseWriter, r *http.Request) {
	n := negotiation.New(r.Header)

	if n.ContentType("application/json") != "" {
		// ...
	}

}

package main

import (
	"net/http"
	"gitlab.schukai.com/oss/libraries/go/network/http-negotiation"
)

func handleRequest(w http.ResponseWriter, r *http.Request) {
	n := negotiation.New(r.Header)

	if n.Language("en-GB", "en") != "en" {
		// ...
	}

}

package main

import (
	"net/http"
	"gitlab.schukai.com/oss/libraries/go/network/http-negotiation"
)

func handleRequest(w http.ResponseWriter, r *http.Request) {
	n := negotiation.New(r.Header)

	if n.Charset("utf-8", "iso-8859-1") != "utf-8" {
		// ...
	}

}

package main

import (
	"net/http"
	"gitlab.schukai.com/oss/libraries/go/network/http-negotiation"
)

func handleRequest(w http.ResponseWriter, r *http.Request) {
	n := negotiation.New(r.Header)

	if n.Encoding("gzip", "deflate") != "gzip" {
		// ...
	}

}