certViewer/cmd/web/middleware.go

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package main

import (
	"fmt"
	"net/http"
)

// secureHeaders follows some security best practices
func secureHeaders(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Security-Policy",
			"default-src 'self'; style-src 'self' fonts.googleapis.com; font-src fonts.gstatic.com")

		w.Header().Set("Referrer-Policy", "origin-when-cross-origin")
		w.Header().Set("X-Content-Type-Options", "nosniff")
		w.Header().Set("X-Frame-Options", "deny")
		w.Header().Set("X-XSS-Protection", "0")

		next.ServeHTTP(w, r)
	})
}

// logRequest handles logging of requests to server
func (app *application) logRequest(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		var (
			ip     = r.RemoteAddr
			proto  = r.Proto
			method = r.Method
			uri    = r.URL.RequestURI()
		)

		app.logger.Info("Received request", "ip", ip, "proto", proto, "method", method, "uri", uri)

		next.ServeHTTP(w, r)
	})
}

// recoverPanic recovers from server panics and returns an error instead
func (app *application) recoverPanic(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		defer func() {
			if err := recover(); err != nil {
				w.Header().Set("Connection", "close")
				app.serverError(w, r, fmt.Errorf("%s", err))
			}
		}()

		next.ServeHTTP(w, r)
	})
}