add support for subpath in play kube for named volumes

subpath allows for only a subdirecty of a volumes data to be mounted in the container add support for the named volume type sub path with others to follow. resolves containers#12929 Signed-off-by: Charlie Doern <[email protected]>
cdoern · Dec 12, 2022 · 95cc7e0 · 95cc7e0
1 parent 6f1bc98
commit 95cc7e0
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diff --git a/libpod/container.go b/libpod/container.go
@@ -254,6 +254,8 @@ type ContainerNamedVolume struct {
 	// IsAnonymous sets the named volume as anonymous even if it has a name
 	// This is used for emptyDir volumes from a kube yaml
 	IsAnonymous bool `json:"setAnonymous,omitempty"`
+	// SubPath determines which part of the Source will be mounted in the container
+	SubPath string
 }
 
 // ContainerOverlayVolume is an overlay volume that will be mounted into the
@@ -440,6 +442,7 @@ func (c *Container) NamedVolumes() []*ContainerNamedVolume {
 		newVol.Name = vol.Name
 		newVol.Dest = vol.Dest
 		newVol.Options = vol.Options
+		newVol.SubPath = vol.SubPath
 		volumes = append(volumes, newVol)
 	}
 

diff --git a/libpod/container_internal_common.go b/libpod/container_internal_common.go
@@ -157,6 +157,10 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) {
 			return nil, err
 		}
 
+		if len(namedVol.SubPath) > 0 {
+			mountPoint = filepath.Join(mountPoint, namedVol.SubPath)
+		}
+
 		overlayFlag := false
 		upperDir := ""
 		workDir := ""

diff --git a/libpod/options.go b/libpod/options.go
@@ -1440,6 +1440,7 @@ func WithNamedVolumes(volumes []*ContainerNamedVolume) CtrCreateOption {
 				Dest:        vol.Dest,
 				Options:     mountOpts,
 				IsAnonymous: vol.IsAnonymous,
+				SubPath:     vol.SubPath,
 			})
 		}
 

diff --git a/pkg/specgen/generate/container_create.go b/pkg/specgen/generate/container_create.go
@@ -404,6 +404,7 @@ func createContainerOptions(rt *libpod.Runtime, s *specgen.SpecGenerator, pod *l
 				Dest:        v.Dest,
 				Options:     v.Options,
 				IsAnonymous: v.IsAnonymous,
+				SubPath:     v.SubPath,
 			})
 		}
 		options = append(options, libpod.WithNamedVolumes(vols))

diff --git a/pkg/specgen/generate/kube/kube.go b/pkg/specgen/generate/kube/kube.go
@@ -395,6 +395,7 @@ func ToSpecGen(ctx context.Context, opts *CtrSpecGenOptions) (*specgen.SpecGener
 				Dest:    volume.MountPath,
 				Name:    volumeSource.Source,
 				Options: options,
+				SubPath: volume.SubPath,
 			}
 			s.Volumes = append(s.Volumes, &namedVolume)
 		case KubeVolumeTypeConfigMap:

diff --git a/pkg/specgen/volumes.go b/pkg/specgen/volumes.go
@@ -27,6 +27,8 @@ type NamedVolume struct {
 	// IsAnonymous sets the named volume as anonymous even if it has a name
 	// This is used for emptyDir volumes from a kube yaml
 	IsAnonymous bool
+	// SubPath stores the sub directory of the named volume to be mounted in the container
+	SubPath string
 }
 
 // OverlayVolume holds information about an overlay volume that will be mounted into

diff --git a/test/e2e/play_kube_test.go b/test/e2e/play_kube_test.go
@@ -247,6 +247,28 @@ spec:
     - containerPort: 80
 `
 
+var subpathTest = `
+apiVersion: v1
+kind: Pod
+metadata:
+  name: testpod
+spec:
+    containers:
+    - name: testctr
+      image: quay.io/libpod/alpine_nginx:latest
+      command:
+        - sleep
+        - inf
+      volumeMounts:
+      - mountPath: /var
+        name: testing
+        subPath: testing/onlythis
+    volumes:
+    - name: testing
+      persistentVolumeClaim:
+        claimName: testvol
+`
+
 var checkInfraImagePodYaml = `
 apiVersion: v1
 kind: Pod
@@ -4460,4 +4482,39 @@ spec:
 		Expect(ps.OutputToStringArray()).To(HaveLen(0))
 	})
 
+	It("podman play kube with named volume subpaths", func() {
+		SkipIfRemote("volume export does not exist on remote")
+		volumeCreate := podmanTest.Podman([]string{"volume", "create", "testvol1"})
+		volumeCreate.WaitWithDefaultTimeout()
+		Expect(volumeCreate).Should(Exit(0))
+
+		session := podmanTest.Podman([]string{"run", "--volume", "testvol1:/data", ALPINE, "sh", "-c", "mkdir -p /data/testing/onlythis && touch /data/testing/onlythis/123.txt && echo hi >> /data/testing/onlythis/123.txt"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		tar := filepath.Join(podmanTest.TempDir, "out.tar")
+		session = podmanTest.Podman([]string{"volume", "export", "--output", tar, "testvol1"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		volumeCreate = podmanTest.Podman([]string{"volume", "create", "testvol"})
+		volumeCreate.WaitWithDefaultTimeout()
+		Expect(volumeCreate).Should(Exit(0))
+
+		volumeImp := podmanTest.Podman([]string{"volume", "import", "testvol", filepath.Join(podmanTest.TempDir, "out.tar")})
+		volumeImp.WaitWithDefaultTimeout()
+		Expect(volumeImp).Should(Exit(0))
+
+		err = writeYaml(subpathTest, kubeYaml)
+		Expect(err).ToNot(HaveOccurred())
+
+		playKube := podmanTest.Podman([]string{"play", "kube", kubeYaml})
+		playKube.WaitWithDefaultTimeout()
+		Expect(playKube).Should(Exit(0))
+
+		exec := podmanTest.Podman([]string{"exec", "-it", "testpod-testctr", "cat", "/var/123.txt"})
+		exec.WaitWithDefaultTimeout()
+		Expect(exec).Should(Exit(0))
+		Expect(exec.OutputToString()).Should(Equal("hi"))
+	})
 })