traefik/middlewares/stripPrefixRegex.go

61 lines
1.7 KiB
Go

package middlewares
import (
"context"
"net/http"
"github.com/containous/mux"
"github.com/containous/traefik/log"
)
// StripPrefixRegex is a middleware used to strip prefix from an URL request
type StripPrefixRegex struct {
Handler http.Handler
router *mux.Router
}
// NewStripPrefixRegex builds a new StripPrefixRegex given a handler and prefixes
func NewStripPrefixRegex(handler http.Handler, prefixes []string) *StripPrefixRegex {
stripPrefix := StripPrefixRegex{Handler: handler, router: mux.NewRouter()}
for _, prefix := range prefixes {
stripPrefix.router.PathPrefix(prefix)
}
return &stripPrefix
}
func (s *StripPrefixRegex) ServeHTTP(w http.ResponseWriter, r *http.Request) {
var match mux.RouteMatch
if s.router.Match(r, &match) {
params := make([]string, 0, len(match.Vars)*2)
for key, val := range match.Vars {
params = append(params, key)
params = append(params, val)
}
prefix, err := match.Route.URL(params...)
if err != nil || len(prefix.Path) > len(r.URL.Path) {
log.Error("Error in stripPrefix middleware", err)
return
}
trailingSlash := r.URL.Path == prefix.Path+"/"
r.URL.Path = r.URL.Path[len(prefix.Path):]
if r.URL.RawPath != "" {
r.URL.RawPath = r.URL.RawPath[len(prefix.Path):]
}
r = r.WithContext(context.WithValue(r.Context(), StripPrefixSlashKey, trailingSlash))
r = r.WithContext(context.WithValue(r.Context(), StripPrefixKey, prefix.Path))
r.Header.Add(ForwardedPrefixHeader, prefix.Path)
r.RequestURI = r.URL.RequestURI()
s.Handler.ServeHTTP(w, r)
return
}
http.NotFound(w, r)
}
// SetHandler sets handler
func (s *StripPrefixRegex) SetHandler(Handler http.Handler) {
s.Handler = Handler
}