add podman volume reload to sync volume plugins

Libpod requires that all volumes are stored in the libpod db. Because
volume plugins can be created outside of podman, it will not show all
available plugins. This podman volume reload command allows users to
sync the libpod db with their external volume plugins. All new volumes
from the plugin are also created in the libpod db and when a volume from
the db no longer exists it will be removed if possible.

There are some problems:
- naming conflicts, in this case we only use the first volume we found.
  This is not deterministic.
- race conditions, we have no control over the volume plugins. It is
  possible that the volumes changed while we run this command.

Fixes #14207

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

4 files changed, 15 insertions, 0 deletions

diff --git a/pkg/domain/entities/engine_container.go b/pkg/domain/entities/engine_container.go
index df42876f6..e4eb808b4 100644
--- a/pkg/domain/entities/engine_container.go
+++ b/pkg/domain/entities/engine_container.go
@@ -104,4 +104,5 @@ type ContainerEngine interface {
 	VolumePrune(ctx context.Context, options VolumePruneOptions) ([]*reports.PruneReport, error)
 	VolumeRm(ctx context.Context, namesOrIds []string, opts VolumeRmOptions) ([]*VolumeRmReport, error)
 	VolumeUnmount(ctx context.Context, namesOrIds []string) ([]*VolumeUnmountReport, error)
+	VolumeReload(ctx context.Context) (*VolumeReloadReport, error)
 }
diff --git a/pkg/domain/entities/volumes.go b/pkg/domain/entities/volumes.go
index 556df16c1..9a06b2238 100644
--- a/pkg/domain/entities/volumes.go
+++ b/pkg/domain/entities/volumes.go
@@ -54,6 +54,11 @@ type VolumeListReport struct {
 	VolumeConfigResponse
 }
 
+// VolumeReloadReport describes the response from reload volume plugins
+type VolumeReloadReport struct {
+	define.VolumeReload
+}
+
 /*
  * Docker API compatibility types
  */
diff --git a/pkg/domain/infra/abi/volumes.go b/pkg/domain/infra/abi/volumes.go
index a9c53c140..1186d8e81 100644
--- a/pkg/domain/infra/abi/volumes.go
+++ b/pkg/domain/infra/abi/volumes.go
@@ -211,3 +211,8 @@ func (ic *ContainerEngine) VolumeUnmount(ctx context.Context, nameOrIDs []string
 
 	return reports, nil
 }
+
+func (ic *ContainerEngine) VolumeReload(ctx context.Context) (*entities.VolumeReloadReport, error) {
+	report := ic.Libpod.UpdateVolumePlugins(ctx)
+	return &entities.VolumeReloadReport{VolumeReload: *report}, nil
+}
diff --git a/pkg/domain/infra/tunnel/volumes.go b/pkg/domain/infra/tunnel/volumes.go
index 33e090148..6ec35e836 100644
--- a/pkg/domain/infra/tunnel/volumes.go
+++ b/pkg/domain/infra/tunnel/volumes.go
@@ -108,3 +108,7 @@ func (ic *ContainerEngine) VolumeMount(ctx context.Context, nameOrIDs []string)
 func (ic *ContainerEngine) VolumeUnmount(ctx context.Context, nameOrIDs []string) ([]*entities.VolumeUnmountReport, error) {
 	return nil, errors.New("unmounting volumes is not supported for remote clients")
 }
+
+func (ic *ContainerEngine) VolumeReload(ctx context.Context) (*entities.VolumeReloadReport, error) {
+	return nil, errors.New("volume reload is not supported for remote clients")
+}