// Package redirect is middleware for redirecting certain requests // to other locations. package redirect import ( "fmt" "html" "net/http" "net/url" "regexp" "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) { for _, rule := range rd.Rules { if rule.From == "/" { // Catchall redirect preserves path (TODO: Standardize/formalize this behavior) toURL, err := url.Parse(rule.To) if err != nil { return http.StatusInternalServerError, err } newPath := toURL.Host + toURL.Path + r.URL.Path rmSlashs := regexp.MustCompile("//+") newPath = rmSlashs.ReplaceAllString(newPath, "/") newPath = toURL.Scheme + "://" + newPath parameters := toURL.Query() for k, v := range r.URL.Query() { parameters.Set(k, v[0]) } if len(parameters) > 0 { newPath = newPath + "?" + parameters.Encode() } if rule.Meta { fmt.Fprintf(w, metaRedir, html.EscapeString(newPath)) } else { http.Redirect(w, r, newPath, rule.Code) } return 0, nil } if r.URL.Path == rule.From { if rule.Meta { fmt.Fprintf(w, metaRedir, html.EscapeString(rule.To)) } else { http.Redirect(w, r, rule.To, rule.Code) } return 0, nil } } return rd.Next.ServeHTTP(w, r) } // Rule describes an HTTP redirect rule. type Rule struct { From, To string Code int Meta bool } var metaRedir = ` redirecting... `