weightlimit" : n,                (numeric) limit of block weight
  "curtime" : ttt,                  (numeric) current timestamp in seconds since epoch (Jan 1 1970 GMT)
  "bits" : "xxxxxxxx",              (string) compressed target of next block
  "height" : n                      (numeric) The height of the next block
}

Examples:
> bitcoin-cli getblocktemplate 
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "getblocktemplate", "params": [] }' -H 'content-type: text/p