Fix up usage and tests, split into multiple files.

Doing this in multiple commits in an attempt to preserve the file movement history.

pkg/scheduler/scheduler.go

@@ -14,129 +14,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package registry
+package scheduler
 
 import (
-	"fmt"
-	"math/rand"
-
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
-	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 )
 
-// Anything that can list minions for a scheduler.
-type MinionLister interface {
-	List() (machines []string, err error)
-}
-
-// Make a MinionLister from a []string
-type StringMinionLister []string
-
-func (s StringMinionLister) List() ([]string, error) {
-	return []string(s), nil
-}
-
-// Scheduler is an interface implemented by things that know how to schedule pods onto machines.
+// Scheduler is an interface implemented by things that know how to schedule pods
+// onto machines.
 type Scheduler interface {
-	Schedule(api.Pod, MinionLister) (string, error)
-}
-
-// RandomScheduler choses machines uniformly at random.
-type RandomScheduler struct {
-	random rand.Rand
-}
-
-func MakeRandomScheduler(random rand.Rand) Scheduler {
-	return &RandomScheduler{
-		random: random,
-	}
-}
-
-func (s *RandomScheduler) Schedule(pod api.Pod, minionLister MinionLister) (string, error) {
-	machines, err := minionLister.List()
-	if err != nil {
-		return "", err
-	}
-	return machines[s.random.Int()%len(machines)], nil
-}
-
-// RoundRobinScheduler chooses machines in order.
-type RoundRobinScheduler struct {
-	currentIndex int
-}
-
-func MakeRoundRobinScheduler() Scheduler {
-	return &RoundRobinScheduler{
-		currentIndex: -1,
-	}
-}
-
-func (s *RoundRobinScheduler) Schedule(pod api.Pod, minionLister MinionLister) (string, error) {
-	machines, err := minionLister.List()
-	if err != nil {
-		return "", err
-	}
-	s.currentIndex = (s.currentIndex + 1) % len(machines)
-	result := machines[s.currentIndex]
-	return result, nil
-}
-
-type FirstFitScheduler struct {
-	registry PodRegistry
-	random   *rand.Rand
-}
-
-func MakeFirstFitScheduler(registry PodRegistry, random *rand.Rand) Scheduler {
-	return &FirstFitScheduler{
-		registry: registry,
-		random:   random,
-	}
-}
-
-func (s *FirstFitScheduler) containsPort(pod api.Pod, port api.Port) bool {
-	for _, container := range pod.DesiredState.Manifest.Containers {
-		for _, podPort := range container.Ports {
-			if podPort.HostPort == port.HostPort {
-				return true
-			}
-		}
-	}
-	return false
-}
-
-func (s *FirstFitScheduler) Schedule(pod api.Pod, minionLister MinionLister) (string, error) {
-	machines, err := minionLister.List()
-	if err != nil {
-		return "", err
-	}
-	machineToPods := map[string][]api.Pod{}
-	pods, err := s.registry.ListPods(labels.Everything())
-	if err != nil {
-		return "", err
-	}
-	for _, scheduledPod := range pods {
-		host := scheduledPod.CurrentState.Host
-		machineToPods[host] = append(machineToPods[host], scheduledPod)
-	}
-	var machineOptions []string
-	for _, machine := range machines {
-		podFits := true
-		for _, scheduledPod := range machineToPods[machine] {
-			for _, container := range pod.DesiredState.Manifest.Containers {
-				for _, port := range container.Ports {
-					if s.containsPort(scheduledPod, port) {
-						podFits = false
-					}
-				}
-			}
-		}
-		if podFits {
-			machineOptions = append(machineOptions, machine)
-		}
-	}
-	if len(machineOptions) == 0 {
-		return "", fmt.Errorf("failed to find fit for %#v", pod)
-	} else {
-		return machineOptions[s.random.Int()%len(machineOptions)], nil
-	}
+	Schedule(api.Pod, MinionLister) (selectedMachine string, err error)
 }