Add k8s proxy

pkg/proxy/error.go

@@ -0,0 +1,15 @@
+package proxy
+
+import "net/http"
+
+var (
+	er = &errorResponder{}
+)
+
+type errorResponder struct {
+}
+
+func (e *errorResponder) Error(w http.ResponseWriter, req *http.Request, err error) {
+	w.WriteHeader(http.StatusInternalServerError)
+	w.Write([]byte(err.Error()))
+}

pkg/proxy/proxy.go

@@ -0,0 +1,101 @@
+package proxy
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/rancher/wrangler/pkg/kubeconfig"
+	utilnet "k8s.io/apimachinery/pkg/util/net"
+	"k8s.io/apimachinery/pkg/util/proxy"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/transport"
+)
+
+// Mostly copied from "kubectl proxy" code
+func HandlerFromConfig(prefix, kubeConfig string) (http.Handler, error) {
+	loader := kubeconfig.GetInteractiveClientConfig(kubeConfig)
+	cfg, err := loader.ClientConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	return Handler(prefix, cfg)
+}
+
+// Mostly copied from "kubectl proxy" code
+func Handler(prefix string, cfg *rest.Config) (http.Handler, error) {
+	host := cfg.Host
+	if !strings.HasSuffix(host, "/") {
+		host = host + "/"
+	}
+	target, err := url.Parse(host)
+	if err != nil {
+		return nil, err
+	}
+
+	transport, err := rest.TransportFor(cfg)
+	if err != nil {
+		return nil, err
+	}
+	upgradeTransport, err := makeUpgradeTransport(cfg, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	proxy := proxy.NewUpgradeAwareHandler(target, transport, false, false, er)
+	proxy.UpgradeTransport = upgradeTransport
+	proxy.UseRequestLocation = true
+
+	if len(prefix) > 2 {
+		return stripLeaveSlash(prefix, proxy), nil
+	}
+
+	return proxy, nil
+}
+
+// like http.StripPrefix, but always leaves an initial slash. (so that our
+// regexps will work.)
+func stripLeaveSlash(prefix string, h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		fmt.Println(req.Method, req.URL.Path)
+		p := strings.TrimPrefix(req.URL.Path, prefix)
+		if len(p) >= len(req.URL.Path) {
+			http.NotFound(w, req)
+			return
+		}
+		if len(p) > 0 && p[:1] != "/" {
+			p = "/" + p
+		}
+		req.URL.Path = p
+		h.ServeHTTP(w, req)
+	})
+}
+
+func makeUpgradeTransport(config *rest.Config, keepalive time.Duration) (proxy.UpgradeRequestRoundTripper, error) {
+	transportConfig, err := config.TransportConfig()
+	if err != nil {
+		return nil, err
+	}
+	tlsConfig, err := transport.TLSConfigFor(transportConfig)
+	if err != nil {
+		return nil, err
+	}
+	rt := utilnet.SetOldTransportDefaults(&http.Transport{
+		TLSClientConfig: tlsConfig,
+		DialContext: (&net.Dialer{
+			Timeout:   30 * time.Second,
+			KeepAlive: keepalive,
+		}).DialContext,
+	})
+
+	upgrader, err := transport.HTTPWrappersForConfig(transportConfig, proxy.MirrorRequest)
+	if err != nil {
+		return nil, err
+	}
+
+	return proxy.NewUpgradeRequestRoundTripper(rt, upgrader), nil
+}

pkg/server/api.go

@@ -6,6 +6,7 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/rancher/naok/pkg/accesscontrol"
 	"github.com/rancher/naok/pkg/attributes"
+	k8sproxy "github.com/rancher/naok/pkg/proxy"
 	"github.com/rancher/naok/pkg/schemas"
 	"github.com/rancher/norman/pkg/api"
 	"github.com/rancher/norman/pkg/store/proxy"
@@ -13,9 +14,14 @@ import (
 	"github.com/rancher/norman/pkg/types"
 	"github.com/rancher/norman/pkg/urlbuilder"
 	"k8s.io/apiserver/pkg/authentication/user"
+	"k8s.io/client-go/rest"
 )
 
-func newAPIServer(cf proxy.ClientGetter, as *accesscontrol.AccessStore, sf schemas.SchemaFactory) http.Handler {
+func newAPIServer(cfg *rest.Config, cf proxy.ClientGetter, as *accesscontrol.AccessStore, sf schemas.SchemaFactory) (http.Handler, error) {
+	var (
+		err error
+	)
+
 	a := &apiServer{
 		Router: mux.NewRouter(),
 		cf:     cf,
@@ -23,10 +29,15 @@ func newAPIServer(cf proxy.ClientGetter, as *accesscontrol.AccessStore, sf schem
 		sf:     sf,
 		server: api.NewAPIServer(),
 	}
+
+	a.Router.NotFoundHandler, err = k8sproxy.Handler("/", cfg)
+	if err != nil {
+		return nil, err
+	}
+
 	a.Router.StrictSlash(true)
 	a.server.AccessControl = accesscontrol.NewAccessControl()
-	a.routes()
-	return a
+	return a, a.routes()
 }
 
 type apiServer struct {

pkg/server/routes.go

@@ -3,16 +3,15 @@ package server
 import (
 	"net/http"
 
-	"github.com/rancher/naok/pkg/attributes"
-
 	"github.com/gorilla/mux"
+	"github.com/rancher/naok/pkg/attributes"
 	"github.com/rancher/norman/pkg/types"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 )
 
 type APIFunc func(*types.APIRequest)
 
-func (a *apiServer) routes() {
+func (a *apiServer) routes() error {
 	a.Path("/v1/{type:schemas}").Handler(a.handle(nil))
 	a.Path("/v1/{type:schemas}/{name}").Handler(a.handle(nil))
 	a.Path("/v1/{type:subscribe}").Handler(a.handle(nil))
@@ -23,6 +22,8 @@ func (a *apiServer) routes() {
 
 	a.Path("/v1/apis/{group}/{version}/{resource}").Handler(a.handle(a.k8sAPI))
 	a.Path("/v1/apis/{group}/{version}/{resource}/{nameorns}").Handler(a.handle(a.k8sAPI))
+
+	return nil
 }
 
 func (a *apiServer) handle(apiFunc APIFunc) http.Handler {