From fb0a7a9693b01443d2db7a5f76fc565bd018d9af Mon Sep 17 00:00:00 2001
From: Tim Hockin <thockin@google.com>
Date: Mon, 22 Dec 2014 15:02:16 -0800
Subject: [PATCH] Add apiserver proxy support for pods.

This is useful for testing mostly.
---
 pkg/registry/pod/rest.go      |  44 +++++++++++++
 pkg/registry/pod/rest_test.go | 114 +++++++++++++++++++++++++++++++---
 2 files changed, 149 insertions(+), 9 deletions(-)

diff --git a/pkg/registry/pod/rest.go b/pkg/registry/pod/rest.go
index 270f1aaa8ec..3b78a068608 100644
--- a/pkg/registry/pod/rest.go
+++ b/pkg/registry/pod/rest.go
@@ -18,6 +18,7 @@ package pod
 
 import (
 	"fmt"
+	"strings"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
@@ -175,3 +176,46 @@ func (rs *REST) Update(ctx api.Context, obj runtime.Object) (<-chan apiserver.RE
 		return rs.registry.GetPod(ctx, pod.Name)
 	}), nil
 }
+
+// ResourceLocation returns a URL to which one can send traffic for the specified pod.
+func (rs *REST) ResourceLocation(ctx api.Context, id string) (string, error) {
+	// Allow ID as "podname" or "podname:port".  If port is not specified,
+	// try to use the first defined port on the pod.
+	parts := strings.Split(id, ":")
+	if len(parts) > 2 {
+		return "", errors.NewBadRequest(fmt.Sprintf("invalid pod request %q", id))
+	}
+	name := parts[0]
+	port := ""
+	if len(parts) == 2 {
+		// TODO: if port is not a number but a "(container)/(portname)", do a name lookup.
+		port = parts[1]
+	}
+
+	obj, err := rs.Get(ctx, name)
+	if err != nil {
+		return "", err
+	}
+	pod := obj.(*api.Pod)
+	if pod == nil {
+		return "", nil
+	}
+
+	// Try to figure out a port.
+	if port == "" {
+		for i := range pod.Spec.Containers {
+			if len(pod.Spec.Containers[i].Ports) > 0 {
+				port = fmt.Sprintf("%d", pod.Spec.Containers[i].Ports[0].ContainerPort)
+				break
+			}
+		}
+	}
+
+	// We leave off the scheme ('http://') because we have no idea what sort of server
+	// is listening at this endpoint.
+	loc := pod.Status.PodIP
+	if port != "" {
+		loc += fmt.Sprintf(":%s", port)
+	}
+	return loc, nil
+}
diff --git a/pkg/registry/pod/rest_test.go b/pkg/registry/pod/rest_test.go
index e93853c69f6..0b63cf726b6 100644
--- a/pkg/registry/pod/rest_test.go
+++ b/pkg/registry/pod/rest_test.go
@@ -443,15 +443,6 @@ func TestCreatePod(t *testing.T) {
 	}
 }
 
-type FakePodInfoGetter struct {
-	info api.PodInfo
-	err  error
-}
-
-func (f *FakePodInfoGetter) GetPodInfo(host, podNamespace string, podID string) (api.PodContainerInfo, error) {
-	return api.PodContainerInfo{ContainerInfo: f.info}, f.err
-}
-
 func TestCreatePodWithConflictingNamespace(t *testing.T) {
 	storage := REST{}
 	pod := &api.Pod{
@@ -487,3 +478,108 @@ func TestUpdatePodWithConflictingNamespace(t *testing.T) {
 		t.Errorf("Expected 'Pod.Namespace does not match the provided context' error, got '%v'", err.Error())
 	}
 }
+
+func TestResourceLocation(t *testing.T) {
+	expectedIP := "1.2.3.4"
+	testCases := []struct {
+		pod      api.Pod
+		query    string
+		location string
+	}{
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+			},
+			query:    "foo",
+			location: expectedIP,
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+			},
+			query:    "foo:12345",
+			location: expectedIP + ":12345",
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{Name: "ctr"},
+					},
+				},
+			},
+			query:    "foo",
+			location: expectedIP,
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{Name: "ctr", Ports: []api.Port{{ContainerPort: 9376}}},
+					},
+				},
+			},
+			query:    "foo",
+			location: expectedIP + ":9376",
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{Name: "ctr", Ports: []api.Port{{ContainerPort: 9376}}},
+					},
+				},
+			},
+			query:    "foo:12345",
+			location: expectedIP + ":12345",
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{Name: "ctr1"},
+						{Name: "ctr2", Ports: []api.Port{{ContainerPort: 9376}}},
+					},
+				},
+			},
+			query:    "foo",
+			location: expectedIP + ":9376",
+		},
+		{
+			pod: api.Pod{
+				ObjectMeta: api.ObjectMeta{Name: "foo"},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{Name: "ctr1", Ports: []api.Port{{ContainerPort: 9376}}},
+						{Name: "ctr2", Ports: []api.Port{{ContainerPort: 1234}}},
+					},
+				},
+			},
+			query:    "foo",
+			location: expectedIP + ":9376",
+		},
+	}
+
+	for _, tc := range testCases {
+		podRegistry := registrytest.NewPodRegistry(nil)
+		podRegistry.Pod = &tc.pod
+		storage := &REST{
+			registry: podRegistry,
+			podCache: &fakeCache{statusToReturn: &api.PodStatus{PodIP: expectedIP}},
+		}
+
+		redirector := apiserver.Redirector(storage)
+		location, err := redirector.ResourceLocation(api.NewDefaultContext(), tc.query)
+		if err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+
+		if location != tc.location {
+			t.Errorf("Expected %v, but got %v", tc.location, location)
+		}
+	}
+}