Merge pull request #71 from brendandburns/container_info

Fix some problems in container info handling if the container's no present.

cmd/cloudcfg/cloudcfg.go

@@ -180,7 +180,7 @@ func main() {
 	}
 	body, err := cloudcfg.DoRequest(request, auth)
 	if err != nil {
-		log.Fatalf("Error: %#v", err)
+		log.Fatalf("Error: %#v %s", err, body)
 	}
 	err = printer.Print(body, os.Stdout)
 	if err != nil {

pkg/kubelet/kubelet.go

@@ -155,26 +155,32 @@ func (kl *Kubelet) ContainerExists(manifest *api.ContainerManifest, container *a
 	return false, "", nil
 }
 
-func (kl *Kubelet) GetContainerID(name string) (string, error) {
+// GetContainerID looks at the list of containers on the machine and returns the ID of the container whose name
+// matches 'name'.  It returns the name of the container, or empty string, if the container isn't found.
+// it returns true if the container is found, false otherwise, and any error that occurs.
+func (kl *Kubelet) GetContainerID(name string) (string, bool, error) {
 	containerList, err := kl.DockerClient.ListContainers(docker.ListContainersOptions{})
 	if err != nil {
-		return "", err
+		return "", false, err
 	}
 	for _, value := range containerList {
 		if strings.Contains(value.Names[0], name) {
-			return value.ID, nil
+			return value.ID, true, nil
 		}
 	}
-	return "", fmt.Errorf("couldn't find name: %s", name)
+	return "", false, nil
 }
 
 // Get a container by name.
 // returns the container data from Docker, or an error if one exists.
 func (kl *Kubelet) GetContainerByName(name string) (*docker.Container, error) {
-	id, err := kl.GetContainerID(name)
+	id, found, err := kl.GetContainerID(name)
 	if err != nil {
 		return nil, err
 	}
+	if !found {
+		return nil, nil
+	}
 	return kl.DockerClient.InspectContainer(id)
 }
 
@@ -317,10 +323,15 @@ func (kl *Kubelet) RunContainer(manifest *api.ContainerManifest, container *api.
 }
 
 func (kl *Kubelet) KillContainer(name string) error {
-	id, err := kl.GetContainerID(name)
+	id, found, err := kl.GetContainerID(name)
 	if err != nil {
 		return err
 	}
+	if !found {
+		// This is weird, but not an error, so yell and then return nil
+		log.Printf("Couldn't find container: %s", name)
+		return nil
+	}
 	err = kl.DockerClient.StopContainer(id, 10)
 	manifestId, containerName := dockerNameToManifestAndContainer(name)
 	kl.LogEvent(&api.Event{

pkg/kubelet/kubelet_server.go

@@ -34,7 +34,7 @@ type KubeletServer struct {
 // kubeletInterface contains all the kubelet methods required by the server.
 // For testablitiy.
 type kubeletInterface interface {
-	GetContainerID(name string) (string, error)
+	GetContainerID(name string) (string, bool, error)
 	GetContainerInfo(name string) (string, error)
 }
 
@@ -71,7 +71,12 @@ func (s *KubeletServer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 			fmt.Fprint(w, "Missing container query arg.")
 			return
 		}
-		id, err := s.Kubelet.GetContainerID(container)
+		id, found, err := s.Kubelet.GetContainerID(container)
+		if (!found) {
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprint(w, "{}")
+			return
+		}
 		body, err := s.Kubelet.GetContainerInfo(id)
 		if err != nil {
 			w.WriteHeader(http.StatusInternalServerError)

pkg/kubelet/kubelet_server_test.go

@@ -16,14 +16,14 @@ import (
 
 type fakeKubelet struct {
 	infoFunc func(name string) (string, error)
-	idFunc   func(name string) (string, error)
+	idFunc   func(name string) (string, bool, error)
 }
 
 func (fk *fakeKubelet) GetContainerInfo(name string) (string, error) {
 	return fk.infoFunc(name)
 }
 
-func (fk *fakeKubelet) GetContainerID(name string) (string, error) {
+func (fk *fakeKubelet) GetContainerID(name string) (string, bool, error) {
 	return fk.idFunc(name)
 }
 
@@ -105,11 +105,11 @@ func TestContainer(t *testing.T) {
 func TestContainerInfo(t *testing.T) {
 	fw := makeServerTest()
 	expected := "good container info string"
-	fw.fakeKubelet.idFunc = func(name string) (string, error) {
+	fw.fakeKubelet.idFunc = func(name string) (string, bool, error) {
 		if name == "goodcontainer" {
-			return name, nil
+			return name, true, nil
 		}
-		return "", fmt.Errorf("bad container")
+		return "", false, fmt.Errorf("bad container")
 	}
 	fw.fakeKubelet.infoFunc = func(name string) (string, error) {
 		if name == "goodcontainer" {

pkg/kubelet/kubelet_test.go

@@ -153,6 +153,12 @@ func verifyPackUnpack(t *testing.T, manifestId, containerName string) {
 	}
 }
 
+func verifyBoolean(t *testing.T, expected, value bool) {
+	if expected != value {
+		t.Errorf("Unexpected boolean.  Expected %s.  Found %s", expected, value)
+	}
+}
+
 func TestContainerManifestNaming(t *testing.T) {
 	verifyPackUnpack(t, "manifest1234", "container5678")
 	verifyPackUnpack(t, "manifest--", "container__")
@@ -222,20 +228,23 @@ func TestGetContainerID(t *testing.T) {
 		},
 	}
 
-	id, err := kubelet.GetContainerID("foo")
+	id, found, err := kubelet.GetContainerID("foo")
+	verifyBoolean(t, true, found)
 	verifyStringEquals(t, id, "1234")
 	verifyNoError(t, err)
 	verifyCalls(t, fakeDocker, []string{"list"})
 	fakeDocker.clearCalls()
 
-	id, err = kubelet.GetContainerID("bar")
+	id, found, err = kubelet.GetContainerID("bar")
+	verifyBoolean(t, true, found)
 	verifyStringEquals(t, id, "4567")
 	verifyNoError(t, err)
 	verifyCalls(t, fakeDocker, []string{"list"})
 	fakeDocker.clearCalls()
 
-	id, err = kubelet.GetContainerID("NotFound")
+	id, found, err = kubelet.GetContainerID("NotFound")
-	verifyError(t, err)
+	verifyBoolean(t, false, found)
+	verifyNoError(t, err)
 	verifyCalls(t, fakeDocker, []string{"list"})
 }