traefik/middlewares/stripPrefix.go
Josh Toft bc0121808a Fix behavior for PathPrefixStrip
When pushing data to downstream proxies; malformed requests were being
sent.

The corrected behavior is as follows:

| Route Stripped    |     URL                |  Passed to Backend |
| ----------------- | ---------------------- | ------------------ |
| /                 |     /                  |  /                 |

| Route Stripped    |     URL                |  Passed to Backend |
| ----------------- | ---------------------- | ------------------ |
| /stat             |     /stat              |  /                 |
| /stat             |     /stat/             |  /                 |
| /stat             |     /status            |  /status           |
| /stat             |     /stat/us           |  /us               |

| Route Stripped    |     URL                |  Passed to Backend |
| ----------------- | ---------------------- | ------------------ |
| /stat/            |     /stat              |  /stat             |
| /stat/            |     /stat/             |  /                 |
| /stat/            |     /status            |  /status           |
| /stat/            |     /stat/us           |  /us               |

Prior, we could strip the prefixing `/`, and we'd also ignore the case
where you want to serve something like `/api` as both the index and as a
subpath.

Additionally, this should resolve a myriad of issues relating to
kubernetes ingress `PathPrefixStrip`.
2017-05-24 10:50:12 +02:00

46 lines
1.1 KiB
Go

package middlewares
import (
"net/http"
"strings"
)
const (
forwardedPrefixHeader = "X-Forwarded-Prefix"
)
// StripPrefix is a middleware used to strip prefix from an URL request
type StripPrefix struct {
Handler http.Handler
Prefixes []string
}
func (s *StripPrefix) ServeHTTP(w http.ResponseWriter, r *http.Request) {
for _, prefix := range s.Prefixes {
origPrefix := strings.TrimSpace(prefix)
if origPrefix == r.URL.Path {
r.URL.Path = "/"
s.serveRequest(w, r, origPrefix)
return
}
prefix = strings.TrimSuffix(origPrefix, "/") + "/"
if p := strings.TrimPrefix(r.URL.Path, prefix); len(p) < len(r.URL.Path) {
r.URL.Path = "/" + strings.TrimPrefix(p, "/")
s.serveRequest(w, r, origPrefix)
return
}
}
http.NotFound(w, r)
}
func (s *StripPrefix) serveRequest(w http.ResponseWriter, r *http.Request, prefix string) {
r.Header[forwardedPrefixHeader] = []string{prefix}
r.RequestURI = r.URL.RequestURI()
s.Handler.ServeHTTP(w, r)
}
// SetHandler sets handler
func (s *StripPrefix) SetHandler(Handler http.Handler) {
s.Handler = Handler
}