hackintoshrao/redirect.go

## redirect.go
// Package redirect is middleware for redirecting certain requests
// to other locations.
package redirect

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

	"github.com/mholt/caddy/middleware"
)

// Redirect is middleware to respond with HTTP redirects
type Redirect struct {
	Next  middleware.Handler
	Rules []Rule
}

// ServeHTTP implements the middleware.Handler interface.
func (rd Redirect) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
const metaRedir = `<!DOCTYPE html>
<html>
	<head>
		<script>window.location.replace("%s");</script>
		<meta http-equiv="refresh" content="0; URL='%s'">
	</head>
	<body>Redirecting...</body>
</html>`

	for _, rule := range rd.Rules {
		if (rule.FromPath == "/" || r.URL.Path == rule.FromPath) && schemeMatches(rule, r) {
			to := middleware.NewReplacer(r, nil, "").Replace(rule.To)
			if rule.Meta {
				safeTo := html.EscapeString(to)
				fmt.Fprintf(w, metaRedir, safeTo, safeTo)
			} else {
				http.Redirect(w, r, to, rule.Code)
			}
			return 0, nil
		}
	}
	return rd.Next.ServeHTTP(w, r)
}

func schemeMatches(rule Rule, req *http.Request) bool {
	return (rule.FromScheme == "https" && req.TLS != nil) ||
		(rule.FromScheme != "https" && req.TLS == nil)
}

// Rule describes an HTTP redirect rule.
type Rule struct {
	FromScheme, FromPath, To string
	Code                     int
	Meta                     bool
}

// Script tag comes first since that will better imitate a redirect in the browser's
// history, but the meta tag is a fallback for most non-JS clients.
	// Package redirect is middleware for redirecting certain requests
	// to other locations.
	package redirect

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

	"github.com/mholt/caddy/middleware"
	)

	// Redirect is middleware to respond with HTTP redirects
	type Redirect struct {
	Next middleware.Handler
	Rules []Rule
	}

	// ServeHTTP implements the middleware.Handler interface.
	func (rd Redirect) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
	const metaRedir = `<!DOCTYPE html>
	<html>
	<head>
	<script>window.location.replace("%s");</script>
	<meta http-equiv="refresh" content="0; URL='%s'">
	</head>
	<body>Redirecting...</body>
	</html>`

	for _, rule := range rd.Rules {
	if (rule.FromPath == "/" \|\| r.URL.Path == rule.FromPath) && schemeMatches(rule, r) {
	to := middleware.NewReplacer(r, nil, "").Replace(rule.To)
	if rule.Meta {
	safeTo := html.EscapeString(to)
	fmt.Fprintf(w, metaRedir, safeTo, safeTo)
	} else {
	http.Redirect(w, r, to, rule.Code)
	}
	return 0, nil
	}
	}
	return rd.Next.ServeHTTP(w, r)
	}

	func schemeMatches(rule Rule, req *http.Request) bool {
	return (rule.FromScheme == "https" && req.TLS != nil) \|\|
	(rule.FromScheme != "https" && req.TLS == nil)
	}

	// Rule describes an HTTP redirect rule.
	type Rule struct {
	FromScheme, FromPath, To string
	Code int
	Meta bool
	}

	// Script tag comes first since that will better imitate a redirect in the browser's
	// history, but the meta tag is a fallback for most non-JS clients.