Get CreatedAt from containerd instead of maintaining it ourselves.

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/store/sandbox/metadata.go

@@ -46,9 +46,6 @@ type Metadata struct {
 	Name string
 	// Config is the CRI sandbox config.
 	Config *runtime.PodSandboxConfig
-	// CreatedAt is the created timestamp.
-	// TODO(random-liu): Use containerd container CreatedAt (containerd#933)
-	CreatedAt int64
 	// Pid is the process id of the sandbox.
 	Pid uint32
 	// NetNSPath is the network namespace used by the sandbox.

pkg/store/sandbox/metadata_test.go

@@ -19,7 +19,6 @@ package sandbox
 import (
 	"encoding/json"
 	"testing"
-	"time"
 
 	assertlib "github.com/stretchr/testify/assert"
 	"k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime"
@@ -37,7 +36,6 @@ func TestMetadataEncodeDecode(t *testing.T) {
 				Attempt:   1,
 			},
 		},
-		CreatedAt: time.Now().UnixNano(),
 	}
 	assert := assertlib.New(t)
 	data, err := meta.Encode()

pkg/store/sandbox/sandbox_test.go

@@ -18,7 +18,6 @@ package sandbox
 
 import (
 	"testing"
-	"time"
 
 	assertlib "github.com/stretchr/testify/assert"
 	"k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime"
@@ -40,7 +39,6 @@ func TestSandboxStore(t *testing.T) {
 					Attempt:   1,
 				},
 			},
-			CreatedAt: time.Now().UnixNano(),
 			Pid:       1001,
 			NetNSPath: "TestNetNS-1",
 		},
@@ -55,7 +53,6 @@ func TestSandboxStore(t *testing.T) {
 					Attempt:   2,
 				},
 			},
-			CreatedAt: time.Now().UnixNano(),
 			Pid:       1002,
 			NetNSPath: "TestNetNS-2",
 		},
@@ -70,7 +67,6 @@ func TestSandboxStore(t *testing.T) {
 					Attempt:   3,
 				},
 			},
-			CreatedAt: time.Now().UnixNano(),
 			Pid:       1003,
 			NetNSPath: "TestNetNS-3",
 		},