Add emptyDir volume support to kube play

When a kube yaml has a volume set as empty dir, podman
will create an anonymous volume with the empty dir name and
attach it to the containers running in the pod. When the pod
is removed, the empy dir volume created is also removed.

Add tests and docs for this as well.

Signed-off-by: Urvashi Mohnani <umohnani@redhat.com>

3 files changed, 15 insertions, 6 deletions

diff --git a/libpod/container.go b/libpod/container.go
index 6c05b1084..44a8669fd 100644
--- a/libpod/container.go
+++ b/libpod/container.go
@@ -237,6 +237,9 @@ type ContainerNamedVolume struct {
 	Dest string `json:"dest"`
 	// Options are fstab style mount options
 	Options []string `json:"options,omitempty"`
+	// 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"`
 }
 
 // ContainerOverlayVolume is a overlay volume that will be mounted into the
diff --git a/libpod/options.go b/libpod/options.go
index d31741094..56d5265d2 100644
--- a/libpod/options.go
+++ b/libpod/options.go
@@ -1413,9 +1413,10 @@ func WithNamedVolumes(volumes []*ContainerNamedVolume) CtrCreateOption {
 			}
 
 			ctr.config.NamedVolumes = append(ctr.config.NamedVolumes, &ContainerNamedVolume{
-				Name:    vol.Name,
-				Dest:    vol.Dest,
-				Options: mountOpts,
+				Name:        vol.Name,
+				Dest:        vol.Dest,
+				Options:     mountOpts,
+				IsAnonymous: vol.IsAnonymous,
 			})
 		}
 
diff --git a/libpod/runtime_ctr.go b/libpod/runtime_ctr.go
index 703ae5cbe..b43114fab 100644
--- a/libpod/runtime_ctr.go
+++ b/libpod/runtime_ctr.go
@@ -474,6 +474,11 @@ func (r *Runtime) setupContainer(ctx context.Context, ctr *Container) (_ *Contai
 				return nil, fmt.Errorf("error retrieving named volume %s for new container: %w", vol.Name, err)
 			}
 		}
+		if vol.IsAnonymous {
+			// If SetAnonymous is true, make this an anonymous volume
+			// this is needed for emptyDir volumes from kube yamls
+			isAnonymous = true
+		}
 
 		logrus.Debugf("Creating new volume %s for container", vol.Name)
 
@@ -814,11 +819,11 @@ func (r *Runtime) removeContainer(ctx context.Context, c *Container, force, remo
 					// Ignore error, since podman will report original error
 					volumesFrom, _ := c.volumesFrom()
 					if len(volumesFrom) > 0 {
-						logrus.Debugf("Cleaning up volume not possible since volume is in use (%s)", v)
+						logrus.Debugf("Cleaning up volume not possible since volume is in use (%s)", v.Name)
 						continue
 					}
 				}
-				logrus.Errorf("Cleaning up volume (%s): %v", v, err)
+				logrus.Errorf("Cleaning up volume (%s): %v", v.Name, err)
 			}
 		}
 	}
@@ -968,7 +973,7 @@ func (r *Runtime) evictContainer(ctx context.Context, idOrName string, removeVol
 				continue
 			}
 			if err := r.removeVolume(ctx, volume, false, timeout, false); err != nil && err != define.ErrNoSuchVolume && err != define.ErrVolumeBeingUsed {
-				logrus.Errorf("Cleaning up volume (%s): %v", v, err)
+				logrus.Errorf("Cleaning up volume (%s): %v", v.Name, err)
 			}
 		}
 	}