Merge pull request #7611 from yifan-gu/rkt_syncPod

kubelet/rkt: Add SyncPod() to rkt.

pkg/kubelet/rkt/rkt.go

@@ -33,6 +33,7 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/capabilities"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/credentialprovider"
 	kubecontainer "github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/container"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/prober"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/types"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/volume"
@@ -69,9 +70,13 @@ const (
 // uses systemd, so in order to run this runtime, systemd must be installed
 // on the machine.
 type Runtime struct {
-	systemd *dbus.Conn
-	absPath string
-	config  *Config
+	generator        kubecontainer.RunContainerOptionsGenerator
+	readinessManager *kubecontainer.ReadinessManager
+	prober           prober.Prober
+	systemd          *dbus.Conn
+	// The absolute path to rkt binary.
+	rktBinAbsPath string
+	config        *Config
 	// TODO(yifan): Refactor this to be generic keyring.
 	dockerKeyring credentialprovider.DockerKeyring
 }
@@ -98,14 +103,14 @@ func New(config *Config) (*Runtime, error) {
 	}
 
 	// Test if rkt binary is in $PATH.
-	absPath, err := exec.LookPath(rktBinName)
+	rktBinAbsPath, err := exec.LookPath(rktBinName)
 	if err != nil {
 		return nil, fmt.Errorf("cannot find rkt binary: %v", err)
 	}
 
 	rkt := &Runtime{
 		systemd:       systemd,
-		absPath:       absPath,
+		rktBinAbsPath: rktBinAbsPath,
 		config:        config,
 		dockerKeyring: credentialprovider.NewDockerKeyring(),
 	}
@@ -483,7 +488,7 @@ func (r *Runtime) preparePod(pod *api.Pod, volumeMap map[string]volume.Volume) (
 		return "", false, err
 	}
 
-	runPrepared := fmt.Sprintf("%s run-prepared --private-net=%v %s", r.absPath, pod.Spec.HostNetwork, uuid)
+	runPrepared := fmt.Sprintf("%s run-prepared --private-net=%v %s", r.rktBinAbsPath, !pod.Spec.HostNetwork, uuid)
 	units := []*unit.UnitOption{
 		newUnitOption(unitKubernetesSection, unitRktID, uuid),
 		newUnitOption(unitKubernetesSection, unitPodName, string(b)),

pkg/kubelet/rkt/sync.go

@@ -0,0 +1,95 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rkt
+
+import (
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	kubecontainer "github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/container"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/probe"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/types"
+	"github.com/golang/glog"
+)
+
+// SyncPod syncs the running pod to match the specified desired pod.
+func (r *Runtime) SyncPod(pod *api.Pod, runningPod kubecontainer.Pod, podStatus api.PodStatus) error {
+	podFullName := kubecontainer.GetPodFullName(pod)
+	if len(runningPod.Containers) == 0 {
+		glog.V(4).Infof("Pod %q is not running, will start it", podFullName)
+		// TODO(yifan): Use RunContainerOptionsGeneratior to get volumeMaps, etc.
+		return r.RunPod(pod, nil)
+	}
+
+	// Add references to all containers.
+	unidentifiedContainers := make(map[types.UID]*kubecontainer.Container)
+	for _, c := range runningPod.Containers {
+		unidentifiedContainers[c.ID] = c
+	}
+
+	restartPod := false
+	for _, container := range pod.Spec.Containers {
+		expectedHash := hashContainer(&container)
+
+		c := runningPod.FindContainerByName(container.Name)
+		if c == nil {
+			if kubecontainer.ShouldContainerBeRestarted(&container, pod, &podStatus, r.readinessManager) {
+				glog.V(3).Infof("Container %+v is dead, but RestartPolicy says that we should restart it.", container)
+				// TODO(yifan): Containers in one pod are fate-sharing at this moment, see:
+				// https://github.com/appc/spec/issues/276.
+				restartPod = true
+				break
+			}
+			continue
+		}
+
+		// TODO(yifan): Take care of host network change.
+		containerChanged := c.Hash != 0 && c.Hash != expectedHash
+		if containerChanged {
+			glog.Infof("Pod %q container %q hash changed (%d vs %d), it will be killed and re-created.", podFullName, container.Name, c.Hash, expectedHash)
+			restartPod = true
+			break
+		}
+
+		result, err := r.prober.Probe(pod, podStatus, container, string(c.ID), c.Created)
+		// TODO(vmarmol): examine this logic.
+		if err == nil && result != probe.Success {
+			glog.Infof("Pod %q container %q is unhealthy (probe result: %v), it will be killed and re-created.", podFullName, container.Name, result)
+			restartPod = true
+			break
+		}
+
+		if err != nil {
+			glog.V(2).Infof("Probe container %q failed: %v", container.Name, err)
+		}
+		delete(unidentifiedContainers, c.ID)
+	}
+
+	// If there is any unidentified containers, restart the pod.
+	if len(unidentifiedContainers) > 0 {
+		restartPod = true
+	}
+
+	if restartPod {
+		// TODO(yifan): Handle network plugin.
+		if err := r.KillPod(runningPod); err != nil {
+			return err
+		}
+		if err := r.RunPod(pod, nil); err != nil {
+			return err
+		}
+	}
+	return nil
+}