authentik/internal/web/proxy.go

94 lines
2.7 KiB
Go

package web
import (
"encoding/json"
"fmt"
"net/http"
"net/http/httputil"
"net/url"
"time"
"github.com/prometheus/client_golang/prometheus"
"goauthentik.io/internal/utils/web"
)
func (ws *WebServer) configureProxy() {
// Reverse proxy to the application server
u, _ := url.Parse("http://localhost:8000")
director := func(req *http.Request) {
req.URL.Scheme = u.Scheme
req.URL.Host = u.Host
if _, ok := req.Header["User-Agent"]; !ok {
// explicitly disable User-Agent so it's not set to default value
req.Header.Set("User-Agent", "")
}
if req.TLS != nil {
req.Header.Set("X-Forwarded-Proto", "https")
}
ws.log.WithField("url", req.URL.String()).WithField("headers", req.Header).Trace("tracing request to backend")
}
rp := &httputil.ReverseProxy{Director: director}
rp.ErrorHandler = ws.proxyErrorHandler
rp.ModifyResponse = ws.proxyModifyResponse
ws.m.PathPrefix("/outpost.goauthentik.io").HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
if ws.ProxyServer != nil {
before := time.Now()
ws.ProxyServer.Handle(rw, r)
Requests.With(prometheus.Labels{
"dest": "embedded_outpost",
}).Observe(float64(time.Since(before)))
return
}
ws.proxyErrorHandler(rw, r, fmt.Errorf("proxy not running"))
})
ws.m.Path("/-/health/live/").HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
rw.WriteHeader(204)
})
ws.m.PathPrefix("/").HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
if !ws.p.IsRunning() {
ws.proxyErrorHandler(rw, r, fmt.Errorf("authentik core not running yet"))
return
}
before := time.Now()
if ws.ProxyServer != nil {
if ws.ProxyServer.HandleHost(rw, r) {
Requests.With(prometheus.Labels{
"dest": "embedded_outpost",
}).Observe(float64(time.Since(before)))
return
}
}
Requests.With(prometheus.Labels{
"dest": "py",
}).Observe(float64(time.Since(before)))
ws.log.WithField("host", web.GetHost(r)).Trace("routing to application server")
rp.ServeHTTP(rw, r)
})
}
func (ws *WebServer) proxyErrorHandler(rw http.ResponseWriter, req *http.Request, err error) {
ws.log.WithError(err).Warning("failed to proxy to backend")
rw.WriteHeader(http.StatusBadGateway)
em := fmt.Sprintf("failed to connect to authentik backend: %v", err)
if !ws.p.IsRunning() {
em = "authentik starting..."
}
// return json if the client asks for json
if req.Header.Get("Accept") == "application/json" {
eem, _ := json.Marshal(map[string]string{
"error": em,
})
em = string(eem)
}
_, err = rw.Write([]byte(em))
if err != nil {
ws.log.WithError(err).Warning("failed to write error message")
}
}
func (ws *WebServer) proxyModifyResponse(r *http.Response) error {
r.Header.Set("X-Powered-By", "authentik")
r.Header.Del("Server")
return nil
}