persistent_volumes.go

/*
Copyright 2015 The Kubernetes Authors.

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 e2e

import (
	"fmt"
	"time"

	. "github.com/onsi/ginkgo"
	. "github.com/onsi/gomega"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/kubernetes/pkg/api/v1"
	"k8s.io/kubernetes/pkg/client/clientset_generated/clientset"
	"k8s.io/kubernetes/test/e2e/framework"
)

// Validate PV/PVC, create and verify writer pod, delete the PVC, and validate the PV's
// phase. Note: the PV is deleted in the AfterEach, not here.
func completeTest(f *framework.Framework, c clientset.Interface, ns string, pv *v1.PersistentVolume, pvc *v1.PersistentVolumeClaim) {

	// 1. verify that the PV and PVC have bound correctly
	By("Validating the PV-PVC binding")
	framework.WaitOnPVandPVC(c, ns, pv, pvc)

	// 2. create the nfs writer pod, test if the write was successful,
	//    then delete the pod and verify that it was deleted
	By("Checking pod has write access to PersistentVolume")
	framework.CreateWaitAndDeletePod(f, c, ns, pvc.Name)

	// 3. delete the PVC, wait for PV to become "Released"
	By("Deleting the PVC to invoke the reclaim policy.")
	framework.DeletePVCandValidatePV(c, ns, pvc, pv, v1.VolumeReleased)
}

// Validate pairs of PVs and PVCs, create and verify writer pod, delete PVC and validate
// PV. Ensure each step succeeds.
// Note: the PV is deleted in the AfterEach, not here.
// Note: this func is serialized, we wait for each pod to be deleted before creating the
//   next pod. Adding concurrency is a TODO item.
func completeMultiTest(f *framework.Framework, c clientset.Interface, ns string, pvols framework.PVMap, claims framework.PVCMap, expectPhase v1.PersistentVolumePhase) {

	// 1. verify each PV permits write access to a client pod
	By("Checking pod has write access to PersistentVolumes")
	for pvcKey := range claims {
		pvc, err := c.Core().PersistentVolumeClaims(pvcKey.Namespace).Get(pvcKey.Name, metav1.GetOptions{})
		Expect(err).NotTo(HaveOccurred())
		if len(pvc.Spec.VolumeName) == 0 {
			continue // claim is not bound
		}
		// sanity test to ensure our maps are in sync
		_, found := pvols[pvc.Spec.VolumeName]
		Expect(found).To(BeTrue())
		// TODO: currently a serialized test of each PV
		framework.CreateWaitAndDeletePod(f, c, pvcKey.Namespace, pvcKey.Name)
	}

	// 2. delete each PVC, wait for its bound PV to reach `expectedPhase`
	By("Deleting PVCs to invoke recycler")
	framework.DeletePVCandValidatePVGroup(c, ns, pvols, claims, expectPhase)
}

// Creates a PV, PVC, and ClientPod that will run until killed by test or clean up.
func initializeGCETestSpec(c clientset.Interface, ns string, pvConfig framework.PersistentVolumeConfig, isPrebound bool) (*v1.Pod, *v1.PersistentVolume, *v1.PersistentVolumeClaim) {
	By("Creating the PV and PVC")
	pv, pvc := framework.CreatePVPVC(c, pvConfig, ns, isPrebound)
	framework.WaitOnPVandPVC(c, ns, pv, pvc)

	By("Creating the Client Pod")
	clientPod := framework.CreateClientPod(c, ns, pvc)
	return clientPod, pv, pvc
}

// initNFSserverPod wraps volumes.go's startVolumeServer to return a running nfs host pod
// commonly used by persistent volume testing
func initNFSserverPod(c clientset.Interface, ns string) *v1.Pod {
	return startVolumeServer(c, VolumeTestConfig{
		namespace:   ns,
		prefix:      "nfs",
		serverImage: NfsServerImage,
		serverPorts: []int{2049},
		serverArgs:  []string{"-G", "777", "/exports"},
	})
}

var _ = framework.KubeDescribe("PersistentVolumes [Volume][Serial]", func() {

	// global vars for the Context()s and It()'s below
	f := framework.NewDefaultFramework("pv")
	var c clientset.Interface
	var ns string

	BeforeEach(func() {
		c = f.ClientSet
		ns = f.Namespace.Name
	})

	///////////////////////////////////////////////////////////////////////
	//				NFS
	///////////////////////////////////////////////////////////////////////
	// Testing configurations of a single a PV/PVC pair, multiple evenly paired PVs/PVCs,
	// and multiple unevenly paired PV/PVCs
	framework.KubeDescribe("PersistentVolumes:NFS[Flaky]", func() {

		var (
			nfsServerPod *v1.Pod
			serverIP     string
			pvConfig     framework.PersistentVolumeConfig
		)

		BeforeEach(func() {
			framework.Logf("[BeforeEach] Creating NFS Server Pod")
			nfsServerPod = initNFSserverPod(c, ns)
			serverIP = nfsServerPod.Status.PodIP
			framework.Logf("[BeforeEach] Configuring PersistentVolume")
			pvConfig = framework.PersistentVolumeConfig{
				NamePrefix: "nfs-",
				PVSource: v1.PersistentVolumeSource{
					NFS: &v1.NFSVolumeSource{
						Server:   serverIP,
						Path:     "/exports",
						ReadOnly: false,
					},
				},
			}
		})

		AfterEach(func() {
			framework.DeletePodWithWait(f, c, nfsServerPod)
		})

		Context("with Single PV - PVC pairs", func() {

			var pv *v1.PersistentVolume
			var pvc *v1.PersistentVolumeClaim

			// Note: this is the only code where the pv is deleted.
			AfterEach(func() {
				framework.Logf("AfterEach: Cleaning up test resources.")
				framework.PVPVCCleanup(c, ns, pv, pvc)
			})

			// Individual tests follow:
			//
			// Create an nfs PV, then a claim that matches the PV, and a pod that
			// contains the claim. Verify that the PV and PVC bind correctly, and
			// that the pod can write to the nfs volume.
			It("should create a non-pre-bound PV and PVC: test write access ", func() {
				pv, pvc = framework.CreatePVPVC(c, pvConfig, ns, false)
				completeTest(f, c, ns, pv, pvc)
			})

			// Create a claim first, then a nfs PV that matches the claim, and a
			// pod that contains the claim. Verify that the PV and PVC bind
			// correctly, and that the pod can write to the nfs volume.
			It("create a PVC and non-pre-bound PV: test write access", func() {
				pv, pvc = framework.CreatePVCPV(c, pvConfig, ns, false)
				completeTest(f, c, ns, pv, pvc)
			})

			// Create a claim first, then a pre-bound nfs PV that matches the claim,
			// and a pod that contains the claim. Verify that the PV and PVC bind
			// correctly, and that the pod can write to the nfs volume.
			It("create a PVC and a pre-bound PV: test write access", func() {
				pv, pvc = framework.CreatePVCPV(c, pvConfig, ns, true)
				completeTest(f, c, ns, pv, pvc)
			})

			// Create a nfs PV first, then a pre-bound PVC that matches the PV,
			// and a pod that contains the claim. Verify that the PV and PVC bind
			// correctly, and that the pod can write to the nfs volume.
			It("create a PV and a pre-bound PVC: test write access", func() {
				pv, pvc = framework.CreatePVPVC(c, pvConfig, ns, true)
				completeTest(f, c, ns, pv, pvc)
			})
		})

		// Create multiple pvs and pvcs, all in the same namespace. The PVs-PVCs are
		// verified to bind, though it's not known in advanced which PV will bind to
		// which claim. For each pv-pvc pair create a pod that writes to the nfs mount.
		// Note: when the number of PVs exceeds the number of PVCs the max binding wait
		//   time will occur for each PV in excess. This is expected but the delta
		//   should be kept small so that the tests aren't unnecessarily slow.
		// Note: future tests may wish to incorporate the following:
		//   a) pre-binding, b) create pvcs before pvs, c) create pvcs and pods
		//   in different namespaces.
		Context("with multiple PVs and PVCs all in same ns", func() {

			// define the maximum number of PVs and PVCs supported by these tests
			const maxNumPVs = 10
			const maxNumPVCs = 10
			// create the pv and pvc maps to be reused in the It blocks
			pvols := make(framework.PVMap, maxNumPVs)
			claims := make(framework.PVCMap, maxNumPVCs)

			AfterEach(func() {
				framework.Logf("AfterEach: deleting %v PVCs and %v PVs...", len(claims), len(pvols))
				framework.PVPVCMapCleanup(c, ns, pvols, claims)
			})

			// Create 2 PVs and 4 PVCs.
			// Note: PVs are created before claims and no pre-binding
			It("should create 2 PVs and 4 PVCs: test write access", func() {
				numPVs, numPVCs := 2, 4
				pvols, claims = framework.CreatePVsPVCs(numPVs, numPVCs, c, ns, pvConfig)
				framework.WaitAndVerifyBinds(c, ns, pvols, claims, true)
				completeMultiTest(f, c, ns, pvols, claims, v1.VolumeReleased)
			})

			// Create 3 PVs and 3 PVCs.
			// Note: PVs are created before claims and no pre-binding
			It("should create 3 PVs and 3 PVCs: test write access", func() {
				numPVs, numPVCs := 3, 3
				pvols, claims = framework.CreatePVsPVCs(numPVs, numPVCs, c, ns, pvConfig)
				framework.WaitAndVerifyBinds(c, ns, pvols, claims, true)
				completeMultiTest(f, c, ns, pvols, claims, v1.VolumeReleased)
			})

			// Create 4 PVs and 2 PVCs.
			// Note: PVs are created before claims and no pre-binding.
			It("should create 4 PVs and 2 PVCs: test write access", func() {
				numPVs, numPVCs := 4, 2
				pvols, claims = framework.CreatePVsPVCs(numPVs, numPVCs, c, ns, pvConfig)
				framework.WaitAndVerifyBinds(c, ns, pvols, claims, true)
				completeMultiTest(f, c, ns, pvols, claims, v1.VolumeReleased)
			})
		})

		// This Context isolates and tests the "Recycle" reclaim behavior.  On deprecation of the
		// Recycler, this entire context can be removed without affecting the test suite or leaving behind
		// dead code.
		Context("when invoking the Recycle reclaim policy", func() {
			var pv *v1.PersistentVolume
			var pvc *v1.PersistentVolumeClaim

			BeforeEach(func() {
				pvConfig.ReclaimPolicy = v1.PersistentVolumeReclaimRecycle
				pv, pvc = framework.CreatePVPVC(c, pvConfig, ns, false)
				framework.WaitOnPVandPVC(c, ns, pv, pvc)
			})

			AfterEach(func() {
				framework.Logf("AfterEach: Cleaning up test resources.")
				framework.PVPVCCleanup(c, ns, pv, pvc)
			})

			// This It() tests a scenario where a PV is written to by a Pod, recycled, then the volume checked
			// for files. If files are found, the checking Pod fails, failing the test.  Otherwise, the pod
			// (and test) succeed.
			It("should test that a PV becomes Available and is clean after the PVC is deleted. [Volume][Serial][Flaky]", func() {
				By("Writing to the volume.")
				pod := framework.MakeWritePod(ns, pvc.Name)
				pod, err := c.Core().Pods(ns).Create(pod)
				Expect(err).NotTo(HaveOccurred())
				err = framework.WaitForPodSuccessInNamespace(c, pod.Name, ns)
				Expect(err).NotTo(HaveOccurred())

				framework.DeletePVCandValidatePV(c, ns, pvc, pv, v1.VolumeAvailable)

				By("Re-mounting the volume.")
				pvc = framework.MakePersistentVolumeClaim(ns)
				pvc = framework.CreatePVC(c, ns, pvc)
				err = framework.WaitForPersistentVolumeClaimPhase(v1.ClaimBound, c, ns, pvc.Name, 2*time.Second, 60*time.Second)
				Expect(err).NotTo(HaveOccurred())

				// If a file is detected in /mnt, fail the pod and do not restart it.
				By("Verifying the mount has been cleaned.")
				mount := pod.Spec.Containers[0].VolumeMounts[0].MountPath
				pod = framework.MakePod(ns, pvc.Name, true, fmt.Sprintf("[ $(ls -A %s | wc -l) -eq 0 ] && exit 0 || exit 1", mount))

				pod, err = c.Core().Pods(ns).Create(pod)
				Expect(err).NotTo(HaveOccurred())
				err = framework.WaitForPodSuccessInNamespace(c, pod.Name, ns)
				Expect(err).NotTo(HaveOccurred())
				framework.Logf("Pod exited without failure; the volume has been recycled.")
			})
		})
	})
	///////////////////////////////////////////////////////////////////////
	//				GCE PD
	///////////////////////////////////////////////////////////////////////
	// Testing configurations of single a PV/PVC pair attached to a GCE PD
	framework.KubeDescribe("PersistentVolumes:GCEPD[Flaky]", func() {

		var (
			diskName  string
			node      types.NodeName
			err       error
			pv        *v1.PersistentVolume
			pvc       *v1.PersistentVolumeClaim
			clientPod *v1.Pod
			pvConfig  framework.PersistentVolumeConfig
		)

		BeforeEach(func() {
			framework.SkipUnlessProviderIs("gce")
			By("Initializing Test Spec")
			if diskName == "" {
				diskName, err = framework.CreatePDWithRetry()
				Expect(err).NotTo(HaveOccurred())
				pvConfig = framework.PersistentVolumeConfig{
					NamePrefix: "gce-",
					PVSource: v1.PersistentVolumeSource{
						GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{
							PDName:   diskName,
							FSType:   "ext3",
							ReadOnly: false,
						},
					},
					Prebind: nil,
				}
			}
			clientPod, pv, pvc = initializeGCETestSpec(c, ns, pvConfig, false)
			node = types.NodeName(clientPod.Spec.NodeName)
		})

		AfterEach(func() {
			framework.Logf("AfterEach: Cleaning up test resources")
			if c != nil {
				framework.DeletePodWithWait(f, c, clientPod)
				framework.PVPVCCleanup(c, ns, pv, pvc)
				clientPod = nil
				pvc = nil
				pv = nil
			}
			node, clientPod, pvc, pv = "", nil, nil, nil
		})

		AddCleanupAction(func() {
			if len(diskName) > 0 {
				framework.DeletePDWithRetry(diskName)
			}
		})

		// Attach a persistent disk to a pod using a PVC.
		// Delete the PVC and then the pod.  Expect the pod to succeed in unmounting and detaching PD on delete.
		It("should test that deleting a PVC before the pod does not cause pod deletion to fail on PD detach", func() {

			By("Deleting the Claim")
			framework.DeletePersistentVolumeClaim(c, pvc.Name, ns)
			framework.VerifyGCEDiskAttached(diskName, node)

			By("Deleting the Pod")
			framework.DeletePodWithWait(f, c, clientPod)

			By("Verifying Persistent Disk detach")
			err = waitForPDDetach(diskName, node)
			Expect(err).NotTo(HaveOccurred())
		})

		// Attach a persistent disk to a pod using a PVC.
		// Delete the PV and then the pod.  Expect the pod to succeed in unmounting and detaching PD on delete.
		It("should test that deleting the PV before the pod does not cause pod deletion to fail on PD detach", func() {

			By("Deleting the Persistent Volume")
			framework.DeletePersistentVolume(c, pv.Name)
			framework.VerifyGCEDiskAttached(diskName, node)

			By("Deleting the client pod")
			framework.DeletePodWithWait(f, c, clientPod)

			By("Verifying Persistent Disk detaches")
			err = waitForPDDetach(diskName, node)
			Expect(err).NotTo(HaveOccurred())
		})

		// Test that a Pod and PVC attached to a GCEPD successfully unmounts and detaches when the encompassing Namespace is deleted.
		It("should test that deleting the Namespace of a PVC and Pod causes the successful detach of Persistent Disk", func() {

			By("Deleting the Namespace")
			err := c.Core().Namespaces().Delete(ns, nil)
			Expect(err).NotTo(HaveOccurred())

			err = framework.WaitForNamespacesDeleted(c, []string{ns}, 3*time.Minute)
			Expect(err).NotTo(HaveOccurred())

			By("Verifying Persistent Disk detaches")
			err = waitForPDDetach(diskName, node)
			Expect(err).NotTo(HaveOccurred())
		})
	})
})