如何使用`jq`来获取密钥

My json looks like this :

我的json看起来像这样:

{
  "20160522201409-jobsv1-1": {
    "vmStateDisplayName": "Ready",
    "servers": {
      "20160522201409 jobs_v1 1": {
        "serverStateDisplayName": "Ready",
        "creationDate": "2016-05-22T20:14:22.000+0000",
        "state": "READY",
        "provisionStatus": "PENDING",
        "serverRole": "ROLE",
        "serverType": "SERVER",
        "serverName": "20160522201409 jobs_v1 1",
        "serverId": 2902
      }
    },
    "isAdminNode": true,
    "creationDate": "2016-05-22T20:14:23.000+0000",
    "totalStorage": 15360,
    "shapeId": "ot1",
    "state": "READY",
    "vmId": 4353,
    "hostName": "20160522201409-jobsv1-1",
    "label": "20160522201409 jobs_v1 ADMIN_SERVER 1",
    "ipAddress": "10.252.159.39",
    "publicIpAddress": "10.252.159.39",
    "usageType": "ADMIN_SERVER",
    "role": "ADMIN_SERVER",
    "componentType": "jobs_v1"
  }
}
{