Implement minion registry. Minions now a first-class object.

cmd/integration/integration.go

@@ -39,7 +39,7 @@ func main() {
 	servers := []string{"http://localhost:4001"}
 	log.Printf("Creating etcd client pointing to %v", servers)
 	etcdClient := etcd.NewClient(servers)
-	machineList := []string{"machine"}
+	machineList := registry.MakeMinionRegistry([]string{"machine"})
 
 	reg := registry.MakeEtcdRegistry(etcdClient, machineList)
 

pkg/master/master.go

@@ -34,8 +34,8 @@ type Master struct {
 	podRegistry        registry.PodRegistry
 	controllerRegistry registry.ControllerRegistry
 	serviceRegistry    registry.ServiceRegistry
+	minionRegistry     registry.MinionRegistry
 
-	minions []string
 	random  *rand.Rand
 	storage map[string]apiserver.RESTStorage
 }
@@ -46,37 +46,40 @@ func NewMemoryServer(minions []string, cloud cloudprovider.Interface) *Master {
 		podRegistry:        registry.MakeMemoryRegistry(),
 		controllerRegistry: registry.MakeMemoryRegistry(),
 		serviceRegistry:    registry.MakeMemoryRegistry(),
+		minionRegistry:     registry.MakeMinionRegistry(minions),
 	}
-	m.init(minions, cloud)
+	m.init(cloud)
 	return m
 }
 
 // Returns a new apiserver.
 func New(etcdServers, minions []string, cloud cloudprovider.Interface) *Master {
 	etcdClient := etcd.NewClient(etcdServers)
+	minionRegistry := registry.MakeMinionRegistry(minions)
 	m := &Master{
-		podRegistry:        registry.MakeEtcdRegistry(etcdClient, minions),
-		controllerRegistry: registry.MakeEtcdRegistry(etcdClient, minions),
-		serviceRegistry:    registry.MakeEtcdRegistry(etcdClient, minions),
+		podRegistry:        registry.MakeEtcdRegistry(etcdClient, minionRegistry),
+		controllerRegistry: registry.MakeEtcdRegistry(etcdClient, minionRegistry),
+		serviceRegistry:    registry.MakeEtcdRegistry(etcdClient, minionRegistry),
+		minionRegistry:     minionRegistry,
 	}
-	m.init(minions, cloud)
+	m.init(cloud)
 	return m
 }
 
-func (m *Master) init(minions []string, cloud cloudprovider.Interface) {
+func (m *Master) init(cloud cloudprovider.Interface) {
 	containerInfo := &client.HTTPContainerInfo{
 		Client: http.DefaultClient,
 		Port:   10250,
 	}
 
-	m.minions = minions
 	m.random = rand.New(rand.NewSource(int64(time.Now().Nanosecond())))
 	podCache := NewPodCache(containerInfo, m.podRegistry, time.Second*30)
 	go podCache.Loop()
 	m.storage = map[string]apiserver.RESTStorage{
-		"pods": registry.MakePodRegistryStorage(m.podRegistry, containerInfo, registry.MakeFirstFitScheduler(m.minions, m.podRegistry, m.random), cloud, podCache),
+		"pods": registry.MakePodRegistryStorage(m.podRegistry, containerInfo, registry.MakeFirstFitScheduler(m.minionRegistry, m.podRegistry, m.random), cloud, podCache),
 		"replicationControllers": registry.MakeControllerRegistryStorage(m.controllerRegistry),
-		"services":               registry.MakeServiceRegistryStorage(m.serviceRegistry, cloud, m.minions),
+		"services":               registry.MakeServiceRegistryStorage(m.serviceRegistry, cloud, m.minionRegistry),
+		"minions":                registry.MakeMinionRegistryStorage(m.minionRegistry),
 	}
 
 }

pkg/registry/etcd_registry.go

@@ -32,7 +32,7 @@ import (
 // EtcdRegistry is an implementation of both ControllerRegistry and PodRegistry which is backed with etcd.
 type EtcdRegistry struct {
 	etcdClient      util.EtcdClient
-	machines        []string
+	machines        MinionRegistry
 	manifestFactory ManifestFactory
 }
 
@@ -40,7 +40,7 @@ type EtcdRegistry struct {
 // 'client' is the connection to etcd
 // 'machines' is the list of machines
 // 'scheduler' is the scheduling algorithm to use.
-func MakeEtcdRegistry(client util.EtcdClient, machines []string) *EtcdRegistry {
+func MakeEtcdRegistry(client util.EtcdClient, machines MinionRegistry) *EtcdRegistry {
 	registry := &EtcdRegistry{
 		etcdClient: client,
 		machines:   machines,
@@ -61,7 +61,11 @@ func (registry *EtcdRegistry) helper() *util.EtcdHelper {
 
 func (registry *EtcdRegistry) ListPods(selector labels.Selector) ([]api.Pod, error) {
 	pods := []api.Pod{}
-	for _, machine := range registry.machines {
+	machines, err := registry.machines.List()
+	if err != nil {
+		return nil, err
+	}
+	for _, machine := range machines {
 		var machinePods []api.Pod
 		err := registry.helper().ExtractList("/registry/hosts/"+machine+"/pods", &machinePods)
 		if err != nil {
@@ -175,7 +179,11 @@ func (registry *EtcdRegistry) getPodForMachine(machine, podID string) (pod api.P
 }
 
 func (registry *EtcdRegistry) findPod(podID string) (api.Pod, string, error) {
-	for _, machine := range registry.machines {
+	machines, err := registry.machines.List()
+	if err != nil {
+		return api.Pod{}, "", err
+	}
+	for _, machine := range machines {
 		pod, err := registry.getPodForMachine(machine, podID)
 		if err == nil {
 			return pod, machine, nil

pkg/registry/etcd_registry_test.go

@@ -28,7 +28,7 @@ import (
 )
 
 func MakeTestEtcdRegistry(client util.EtcdClient, machines []string) *EtcdRegistry {
-	registry := MakeEtcdRegistry(client, machines)
+	registry := MakeEtcdRegistry(client, MakeMinionRegistry(machines))
 	registry.manifestFactory = &BasicManifestFactory{
 		serviceRegistry: &MockServiceRegistry{},
 	}

pkg/registry/minion_registry_test.go

@@ -92,7 +92,7 @@ func TestMinionRegistryStorage(t *testing.T) {
 	if err != nil {
 		t.Errorf("got error calling List")
 	}
-	if !reflect.DeepEqual(list.(string), []string{"baz", "foo"}) {
+	if !reflect.DeepEqual(list.([]string), []string{"baz", "foo"}) {
 		t.Errorf("Unexpected list value: %#v", list)
 	}
 }

pkg/registry/scheduler.go

@@ -31,11 +31,11 @@ type Scheduler interface {
 
 // RandomScheduler choses machines uniformly at random.
 type RandomScheduler struct {
-	machines []string
+	machines MinionRegistry
 	random   rand.Rand
 }
 
-func MakeRandomScheduler(machines []string, random rand.Rand) Scheduler {
+func MakeRandomScheduler(machines MinionRegistry, random rand.Rand) Scheduler {
 	return &RandomScheduler{
 		machines: machines,
 		random:   random,
@@ -43,35 +43,43 @@ func MakeRandomScheduler(machines []string, random rand.Rand) Scheduler {
 }
 
 func (s *RandomScheduler) Schedule(pod api.Pod) (string, error) {
-	return s.machines[s.random.Int()%len(s.machines)], nil
+	machines, err := s.machines.List()
+	if err != nil {
+		return "", err
+	}
+	return machines[s.random.Int()%len(machines)], nil
 }
 
 // RoundRobinScheduler chooses machines in order.
 type RoundRobinScheduler struct {
-	machines     []string
+	machines     MinionRegistry
 	currentIndex int
 }
 
-func MakeRoundRobinScheduler(machines []string) Scheduler {
+func MakeRoundRobinScheduler(machines MinionRegistry) Scheduler {
 	return &RoundRobinScheduler{
 		machines:     machines,
-		currentIndex: 0,
+		currentIndex: -1,
 	}
 }
 
 func (s *RoundRobinScheduler) Schedule(pod api.Pod) (string, error) {
-	result := s.machines[s.currentIndex]
-	s.currentIndex = (s.currentIndex + 1) % len(s.machines)
+	machines, err := s.machines.List()
+	if err != nil {
+		return "", err
+	}
+	s.currentIndex = (s.currentIndex + 1) % len(machines)
+	result := machines[s.currentIndex]
 	return result, nil
 }
 
 type FirstFitScheduler struct {
-	machines []string
+	machines MinionRegistry
 	registry PodRegistry
 	random   *rand.Rand
 }
 
-func MakeFirstFitScheduler(machines []string, registry PodRegistry, random *rand.Rand) Scheduler {
+func MakeFirstFitScheduler(machines MinionRegistry, registry PodRegistry, random *rand.Rand) Scheduler {
 	return &FirstFitScheduler{
 		machines: machines,
 		registry: registry,
@@ -91,6 +99,10 @@ func (s *FirstFitScheduler) containsPort(pod api.Pod, port api.Port) bool {
 }
 
 func (s *FirstFitScheduler) Schedule(pod api.Pod) (string, error) {
+	machines, err := s.machines.List()
+	if err != nil {
+		return "", err
+	}
 	machineToPods := map[string][]api.Pod{}
 	pods, err := s.registry.ListPods(labels.Everything())
 	if err != nil {
@@ -101,7 +113,7 @@ func (s *FirstFitScheduler) Schedule(pod api.Pod) (string, error) {
 		machineToPods[host] = append(machineToPods[host], scheduledPod)
 	}
 	var machineOptions []string
-	for _, machine := range s.machines {
+	for _, machine := range machines {
 		podFits := true
 		for _, scheduledPod := range machineToPods[machine] {
 			for _, container := range pod.DesiredState.Manifest.Containers {

pkg/registry/scheduler_test.go

@@ -32,7 +32,7 @@ func expectSchedule(scheduler Scheduler, pod api.Pod, expected string, t *testin
 }
 
 func TestRoundRobinScheduler(t *testing.T) {
-	scheduler := MakeRoundRobinScheduler([]string{"m1", "m2", "m3", "m4"})
+	scheduler := MakeRoundRobinScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3", "m4"}))
 	expectSchedule(scheduler, api.Pod{}, "m1", t)
 	expectSchedule(scheduler, api.Pod{}, "m2", t)
 	expectSchedule(scheduler, api.Pod{}, "m3", t)
@@ -41,7 +41,7 @@ func TestRoundRobinScheduler(t *testing.T) {
 
 func TestRandomScheduler(t *testing.T) {
 	random := rand.New(rand.NewSource(0))
-	scheduler := MakeRandomScheduler([]string{"m1", "m2", "m3", "m4"}, *random)
+	scheduler := MakeRandomScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3", "m4"}), *random)
 	_, err := scheduler.Schedule(api.Pod{})
 	expectNoError(t, err)
 }
@@ -49,7 +49,7 @@ func TestRandomScheduler(t *testing.T) {
 func TestFirstFitSchedulerNothingScheduled(t *testing.T) {
 	mockRegistry := MockPodRegistry{}
 	r := rand.New(rand.NewSource(0))
-	scheduler := MakeFirstFitScheduler([]string{"m1", "m2", "m3"}, &mockRegistry, r)
+	scheduler := MakeFirstFitScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3"}), &mockRegistry, r)
 	expectSchedule(scheduler, api.Pod{}, "m3", t)
 }
 
@@ -81,7 +81,7 @@ func TestFirstFitSchedulerFirstScheduled(t *testing.T) {
 		},
 	}
 	r := rand.New(rand.NewSource(0))
-	scheduler := MakeFirstFitScheduler([]string{"m1", "m2", "m3"}, &mockRegistry, r)
+	scheduler := MakeFirstFitScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3"}), &mockRegistry, r)
 	expectSchedule(scheduler, makePod("", 8080), "m3", t)
 }
 
@@ -94,7 +94,7 @@ func TestFirstFitSchedulerFirstScheduledComplicated(t *testing.T) {
 		},
 	}
 	r := rand.New(rand.NewSource(0))
-	scheduler := MakeFirstFitScheduler([]string{"m1", "m2", "m3"}, &mockRegistry, r)
+	scheduler := MakeFirstFitScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3"}), &mockRegistry, r)
 	expectSchedule(scheduler, makePod("", 8080, 8081), "m3", t)
 }
 
@@ -107,7 +107,7 @@ func TestFirstFitSchedulerFirstScheduledImpossible(t *testing.T) {
 		},
 	}
 	r := rand.New(rand.NewSource(0))
-	scheduler := MakeFirstFitScheduler([]string{"m1", "m2", "m3"}, &mockRegistry, r)
+	scheduler := MakeFirstFitScheduler(MakeMinionRegistry([]string{"m1", "m2", "m3"}), &mockRegistry, r)
 	_, err := scheduler.Schedule(makePod("", 8080, 8081))
 	if err == nil {
 		t.Error("Unexpected non-error.")

pkg/registry/service_registry.go

@@ -30,14 +30,14 @@ import (
 type ServiceRegistryStorage struct {
 	registry ServiceRegistry
 	cloud    cloudprovider.Interface
-	hosts    []string
+	machines MinionRegistry
 }
 
-func MakeServiceRegistryStorage(registry ServiceRegistry, cloud cloudprovider.Interface, hosts []string) apiserver.RESTStorage {
+func MakeServiceRegistryStorage(registry ServiceRegistry, cloud cloudprovider.Interface, machines MinionRegistry) apiserver.RESTStorage {
 	return &ServiceRegistryStorage{
 		registry: registry,
 		cloud:    cloud,
-		hosts:    hosts,
+		machines: machines,
 	}
 }
 
@@ -117,7 +117,11 @@ func (sr *ServiceRegistryStorage) Create(obj interface{}) (<-chan interface{}, e
 			balancer, ok = sr.cloud.TCPLoadBalancer()
 		}
 		if ok && balancer != nil {
-			err := balancer.CreateTCPLoadBalancer(srv.ID, "us-central1", srv.Port, sr.hosts)
+			hosts, err := sr.machines.List()
+			if err != nil {
+				return nil, err
+			}
+			err = balancer.CreateTCPLoadBalancer(srv.ID, "us-central1", srv.Port, hosts)
 			if err != nil {
 				return nil, err
 			}

pkg/registry/service_registry_test.go

@@ -29,7 +29,7 @@ func TestServiceRegistry(t *testing.T) {
 	fakeCloud := &cloudprovider.FakeCloud{}
 	machines := []string{"foo", "bar", "baz"}
 
-	storage := MakeServiceRegistryStorage(memory, fakeCloud, machines)
+	storage := MakeServiceRegistryStorage(memory, fakeCloud, MakeMinionRegistry(machines))
 
 	svc := api.Service{
 		JSONBase: api.JSONBase{ID: "foo"},
@@ -51,7 +51,7 @@ func TestServiceRegistryExternalService(t *testing.T) {
 	fakeCloud := &cloudprovider.FakeCloud{}
 	machines := []string{"foo", "bar", "baz"}
 
-	storage := MakeServiceRegistryStorage(memory, fakeCloud, machines)
+	storage := MakeServiceRegistryStorage(memory, fakeCloud, MakeMinionRegistry(machines))
 
 	svc := api.Service{
 		JSONBase:                   api.JSONBase{ID: "foo"},
@@ -76,7 +76,7 @@ func TestServiceRegistryExternalServiceError(t *testing.T) {
 	}
 	machines := []string{"foo", "bar", "baz"}
 
-	storage := MakeServiceRegistryStorage(memory, fakeCloud, machines)
+	storage := MakeServiceRegistryStorage(memory, fakeCloud, MakeMinionRegistry(machines))
 
 	svc := api.Service{
 		JSONBase:                   api.JSONBase{ID: "foo"},
@@ -99,7 +99,7 @@ func TestServiceRegistryDelete(t *testing.T) {
 	fakeCloud := &cloudprovider.FakeCloud{}
 	machines := []string{"foo", "bar", "baz"}
 
-	storage := MakeServiceRegistryStorage(memory, fakeCloud, machines)
+	storage := MakeServiceRegistryStorage(memory, fakeCloud, MakeMinionRegistry(machines))
 
 	svc := api.Service{
 		JSONBase: api.JSONBase{ID: "foo"},
@@ -123,7 +123,7 @@ func TestServiceRegistryDeleteExternal(t *testing.T) {
 	fakeCloud := &cloudprovider.FakeCloud{}
 	machines := []string{"foo", "bar", "baz"}
 
-	storage := MakeServiceRegistryStorage(memory, fakeCloud, machines)
+	storage := MakeServiceRegistryStorage(memory, fakeCloud, MakeMinionRegistry(machines))
 
 	svc := api.Service{
 		JSONBase:                   api.JSONBase{ID: "foo"},