virtcontainers: sandbox: Add new getter to retrieve netns

As we want to call the OCI hook from the CLI, we need a way for the
CLI to figure out what is the network namespace used by the sandbox.
This is needed particularly because virtcontainers creates the netns
if none was provided.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

virtcontainers/interfaces.go

@@ -59,6 +59,7 @@ type VC interface {
 // (required since virtcontainers.Sandbox only contains private fields)
 type VCSandbox interface {
 	Annotations(key string) (string, error)
+	GetNetNs() string
 	GetAllContainers() []VCContainer
 	GetAnnotations() map[string]string
 	GetContainer(containerID string) VCContainer

virtcontainers/pkg/vcmock/sandbox.go

@@ -36,6 +36,11 @@ func (s *Sandbox) GetAnnotations() map[string]string {
 	return s.MockAnnotations
 }
 
+// GetNetNs returns the network namespace of the current sandbox.
+func (s *Sandbox) GetNetNs() string {
+	return s.MockNetNs
+}
+
 // GetAllContainers implements the VCSandbox function of the same name.
 func (s *Sandbox) GetAllContainers() []vc.VCContainer {
 	var ifa = make([]vc.VCContainer, len(s.MockContainers))

virtcontainers/pkg/vcmock/types.go

@@ -23,6 +23,7 @@ type Sandbox struct {
 	MockURL         string
 	MockAnnotations map[string]string
 	MockContainers  []*Container
+	MockNetNs       string
 }
 
 // Container is a fake Container type used for testing

virtcontainers/sandbox.go

@@ -544,6 +544,11 @@ func (s *Sandbox) GetAnnotations() map[string]string {
 	return s.config.Annotations
 }
 
+// GetNetNs returns the network namespace of the current sandbox.
+func (s *Sandbox) GetNetNs() string {
+	return s.networkNS.NetNsPath
+}
+
 // GetAllContainers returns all containers.
 func (s *Sandbox) GetAllContainers() []VCContainer {
 	ifa := make([]VCContainer, len(s.containers))

virtcontainers/sandbox_test.go

@@ -1706,3 +1706,19 @@ func TestPreAddDevice(t *testing.T) {
 	assert.Equal(t, len(mounts), 0,
 		"mounts should contain nothing because it only contains a block device")
 }
+
+func TestGetNetNs(t *testing.T) {
+	s := Sandbox{}
+
+	expected := ""
+	netNs := s.GetNetNs()
+	assert.Equal(t, netNs, expected)
+
+	expected = "/foo/bar/ns/net"
+	s.networkNS = NetworkNamespace{
+		NetNsPath: expected,
+	}
+
+	netNs = s.GetNetNs()
+	assert.Equal(t, netNs, expected)
+}