Rewrite timestamps in container/sandbox status.

[Random-Liu]

Rewrite timestamps in status to make it more user friendly. After this change:

$ crictl inspects 6ecc8a386012a
{
  "status": {
    "id": "6ecc8a386012aa3d8cc41e986263a56c039044b7f9dcceda012cc3fc045e58c9",
    "metadata": {
      "attempt": 0,
      "name": "kube-dns-6c857864fb-z88p2",
      "namespace": "kube-system",
      "uid": "64489eae-d610-11e7-8e8b-42010af00002"
    },
    "state": "SANDBOX_NOTREADY",
    "createdAt": "2017-11-30T20:52:44.926737345Z",
    "network": {
      "ip": "10.88.22.12"
    },
    "linux": {
      "namespaces": {
        "options": {
          "hostIpc": false,
          "hostNetwork": false,
          "hostPid": false
        }
      }
    },
    "labels": {
      "io.kubernetes.pod.name": "kube-dns-6c857864fb-z88p2",
      "io.kubernetes.pod.namespace": "kube-system",
      "io.kubernetes.pod.uid": "64489eae-d610-11e7-8e8b-42010af00002",
      "k8s-app": "kube-dns",
      "pod-template-hash": "2741342096"
    },
    "annotations": {
      "kubernetes.io/config.seen": "2017-11-30T20:52:41.854730835Z",
      "kubernetes.io/config.source": "api",
      "scheduler.alpha.kubernetes.io/critical-pod": ""
    }
  }
}
$  crictl inspect 98ad5842a6284 -q
{
  "status": {
    "id": "98ad5842a62844f62d4468c52dbfcc081a08ba25c95c842a967de7058f60dd24",
    "metadata": {
      "attempt": 0,
      "name": "nginx"
    },
    "state": "CONTAINER_EXITED",
    "createdAt": "2017-11-30T21:57:26.038813532Z",
    "startedAt": "2017-11-30T21:57:26.235406355Z",
    "finishedAt": "2017-12-01T20:08:56.523559866Z",
    "exitCode": 255,
    "image": {
      "image": "gcr.io/google-containers/nginx-slim-amd64:0.20"
    },
    "imageRef": "gcr.io/google-containers/nginx-slim-amd64@sha256:6654db6d4028756062edac466454ee5c9cf9b20ef79e35a81e3c840031eb1e2b",
    "reason": "Unknown",
    "message": "",
    "labels": {
      "io.kubernetes.container.name": "nginx",
      "io.kubernetes.pod.name": "nginx",
      "io.kubernetes.pod.namespace": "e2e-tests-kubectl-2jdtb",
      "io.kubernetes.pod.uid": "6ffc887b-d619-11e7-8e8b-42010af00002"
    },
    "annotations": {
      "io.kubernetes.container.hash": "cfada9cb",
      "io.kubernetes.container.ports": "[{\"containerPort\":80,\"protocol\":\"TCP\"}]",
      "io.kubernetes.container.restartCount": "0",
      "io.kubernetes.container.terminationMessagePath": "/dev/termination-log",
      "io.kubernetes.container.terminationMessagePolicy": "File",
      "io.kubernetes.pod.terminationGracePeriod": "30"
    },
    "mounts": [
      {
        "containerPath": "/var/run/secrets/kubernetes.io/serviceaccount",
        "hostPath": "/var/lib/kubelet/pods/6ffc887b-d619-11e7-8e8b-42010af00002/volumes/kubernetes.io~secret/default-token-4ztmf",
        "propagation": "PROPAGATION_PRIVATE",
        "readonly": true,
        "selinuxRelabel": false
      },
      {
        "containerPath": "/etc/hosts",
        "hostPath": "/var/lib/kubelet/pods/6ffc887b-d619-11e7-8e8b-42010af00002/etc-hosts",
        "propagation": "PROPAGATION_PRIVATE",
        "readonly": false,
        "selinuxRelabel": false
      },
      {
        "containerPath": "/dev/termination-log",
        "hostPath": "/var/lib/kubelet/pods/6ffc887b-d619-11e7-8e8b-42010af00002/containers/nginx/5f93e895",
        "propagation": "PROPAGATION_PRIVATE",
        "readonly": false,
        "selinuxRelabel": false
      }
    ],
    "logPath": "/var/log/pods/6ffc887b-d619-11e7-8e8b-42010af00002/nginx_0.log"
  }
}

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

[Random-Liu]

/cc @mikebrow

[mikebrow]

The code looks good as one solution to resolve the map order issue. But as seen over here:
containerd/cri#475

We don't really want a map or array of verbose info that is not specified with a predefined field name.

Per the solution used above ^ isn't it much better/easier to just deprecate map and add predefined verbose info structs? Even if we go with map we still need predefined map keys so we know what to look for if we are interested in something specific. And if we go that route we could output the fields we want in any sequence we want. So either way, predefined struct, or predefined keys.. we would not need to sort. Thoughts?

[mikebrow]

thumbs up!

[feiskyer]

Per the solution used above ^ isn't it much better/easier to just deprecate map and add predefined verbose info structs? Even if we go with map we still need predefined map keys so we know what to look for if we are interested in something specific. And if we go that route we could output the fields we want in any sequence we want. So either way, predefined struct, or predefined keys.. we would not need to sort.

Predefined struct or keys are other ways for getting a sorted result. But they need to redefine the sandbox/container/image status structs or hack with struct fields, which seems also not graceful.

I'm ok with current implementation. Let's get this in and iterate with better solutions in the future (if there are).