Merge pull request #139 from superseb/check_local_image

Check image locally before pull

docker/docker.go

@@ -36,12 +36,10 @@ func DoRunContainer(dClient *client.Client, imageCfg *container.Config, hostCfg
 		return nil
 	}
 
-	logrus.Infof("[%s] Pulling Image on host [%s]", plane, hostname)
-	err = PullImage(dClient, hostname, imageCfg.Image)
+	err = UseLocalOrPull(dClient, hostname, imageCfg.Image, plane)
 	if err != nil {
 		return err
 	}
-	logrus.Infof("[%s] Successfully pulled [%s] image on host [%s]", plane, containerName, hostname)
 	resp, err := dClient.ContainerCreate(context.Background(), imageCfg, hostCfg, nil, containerName)
 	if err != nil {
 		return fmt.Errorf("Failed to create [%s] container on host [%s]: %v", containerName, hostname, err)
@@ -64,12 +62,10 @@ func DoRollingUpdateContainer(dClient *client.Client, imageCfg *container.Config
 		logrus.Infof("[%s] Container %s is not running on host [%s]", plane, containerName, hostname)
 		return nil
 	}
-	logrus.Infof("[%s] Pulling Image on host [%s]", plane, hostname)
-	err = PullImage(dClient, hostname, imageCfg.Image)
+	err = UseLocalOrPull(dClient, hostname, imageCfg.Image, plane)
 	if err != nil {
 		return err
 	}
-	logrus.Infof("[%s] Successfully pulled [%s] image on host [%s]", plane, containerName, hostname)
 	logrus.Debugf("[%s] Stopping old container", plane)
 	oldContainerName := "old-" + containerName
 	if err := StopRenameContainer(dClient, hostname, containerName, oldContainerName); err != nil {
@@ -130,7 +126,21 @@ func IsContainerRunning(dClient *client.Client, hostname string, containerName s
 	return false, nil
 }
 
-func PullImage(dClient *client.Client, hostname string, containerImage string) error {
+func localImageExists(dClient *client.Client, hostname string, containerImage string) (bool, error) {
+	logrus.Debugf("Checking if image [%s] exists on host [%s]", containerImage, hostname)
+	_, _, err := dClient.ImageInspectWithRaw(context.Background(), containerImage)
+	if err != nil {
+		if client.IsErrNotFound(err) {
+			logrus.Debugf("Image [%s] does not exist on host [%s]: %v", containerImage, hostname, err)
+			return false, nil
+		}
+		return false, fmt.Errorf("Error checking if image [%s] exists on host [%s]: %v", containerImage, hostname, err)
+	}
+	logrus.Debugf("Image [%s] exists on host [%s]", containerImage, hostname)
+	return true, nil
+}
+
+func pullImage(dClient *client.Client, hostname string, containerImage string) error {
 	out, err := dClient.ImagePull(context.Background(), containerImage, types.ImagePullOptions{})
 	if err != nil {
 		return fmt.Errorf("Can't pull Docker image [%s] for host [%s]: %v", containerImage, hostname, err)
@@ -145,6 +155,24 @@ func PullImage(dClient *client.Client, hostname string, containerImage string) e
 	return nil
 }
 
+func UseLocalOrPull(dClient *client.Client, hostname string, containerImage string, plane string) error {
+	logrus.Infof("[%s] Checking image [%s] on host [%s]", plane, containerImage, hostname)
+	imageExists, err := localImageExists(dClient, hostname, containerImage)
+	if err != nil {
+		return err
+	}
+	if imageExists {
+		logrus.Infof("[%s] No pull necessary, image [%s] exists on host [%s]", plane, containerImage, hostname)
+		return nil
+	}
+	logrus.Infof("[%s] Pulling image [%s] on host [%s]", plane, containerImage, hostname)
+	if err := pullImage(dClient, hostname, containerImage); err != nil {
+		return err
+	}
+	logrus.Infof("[%s] Successfully pulled image [%s] on host [%s]", plane, containerImage, hostname)
+	return nil
+}
+
 func RemoveContainer(dClient *client.Client, hostname string, containerName string) error {
 	err := dClient.ContainerRemove(context.Background(), containerName, types.ContainerRemoveOptions{})
 	if err != nil {

pki/constants.go

@@ -1,6 +1,7 @@
 package pki
 
 const (
+	CertificatesServiceName = "certificates"
 	CrtDownloaderContainer  = "cert-deployer"
 	CertificatesSecretName  = "k8s-certs"
 

pki/deploy.go

@@ -62,8 +62,7 @@ func DeployCertificatesOnWorkers(workerHosts []*hosts.Host, crtMap map[string]Ce
 }
 
 func doRunDeployer(host *hosts.Host, containerEnv []string, certDownloaderImage string) error {
-	logrus.Debugf("[certificates] Pulling Certificate downloader Image on host [%s]", host.Address)
-	if err := docker.PullImage(host.DClient, host.Address, certDownloaderImage); err != nil {
+	if err := docker.UseLocalOrPull(host.DClient, host.Address, certDownloaderImage, CertificatesServiceName); err != nil {
 		return err
 	}
 	imageCfg := &container.Config{

services/services.go

@@ -15,6 +15,8 @@ const (
 	ControlRole = "controlplane"
 	WorkerRole  = "worker"
 
+	SidekickServiceName = "sidekick"
+
 	KubeAPIContainerName        = "kube-api"
 	KubeletContainerName        = "kubelet"
 	KubeproxyContainerName      = "kube-proxy"
@@ -56,11 +58,11 @@ func runSidekick(host *hosts.Host, sidekickImage string) error {
 		return err
 	}
 	if isRunning {
-		logrus.Infof("[sidekick] Sidekick container already created on host [%s]", host.Address)
+		logrus.Infof("[%s] Sidekick container already created on host [%s]", SidekickServiceName, host.Address)
 		return nil
 	}
 	imageCfg, hostCfg := buildSidekickConfig(sidekickImage)
-	if err := docker.PullImage(host.DClient, host.Address, sidekickImage); err != nil {
+	if err := docker.UseLocalOrPull(host.DClient, host.Address, sidekickImage, SidekickServiceName); err != nil {
 		return err
 	}
 	if _, err := docker.CreateContiner(host.DClient, host.Address, SidekickContainerName, imageCfg, hostCfg); err != nil {