Converting timestamp field in JSON using jq-CodePudding

I used Centos7 and jq-1.6. I'm hoping to convert every UTC TimeStamp in the json to Singapore time(SNST=GMT 08:00) I'm currently writing shellscript so I can mix some bash commands if needed.

The json source

api_result='
{
    "DataInterval": 300,
    "EndTime": "2022-07-25T15:15:00Z",
    "HttpCodeData": {
        "UsageData": [
                {
                    "TimeStamp": "2022-07-29T03:00:00Z",
                    "Value": {
                        "CodeProportionData": [
                            {
                                "Code": "404",
                                "Count": 36,
                                "Proportion": 0.022
                            },
                            {
                                "Code": "502",
                                "Count": 3,
                                "Proportion": 0.002
                            }
                        ]
                    }
            },
            {
                    "TimeStamp": "2022-07-29T03:05:00Z",
                    "Value": {
                        "CodeProportionData": [
                            {
                                "Code": "404",
                                "Count": 27,
                                "Proportion": 0.015
                            },
                            {
                                "Code": "502",
                                "Count": 5,
                                "Proportion": 0.002
                            }
                        ]
                    }
            }
    },
    "StartTime": "2022-07-25T15:10:00Z"
}'

My attempt I first tried to convert the timestamp to epoch. But it failed

jq '
    def datestamp2epoch:
        . | scan("(. ?)([.][0-9] )?Z$")
          | [(.[0]   "Z" | fromdateiso8601), (.[1] // 0 | tonumber)]
          | add;
    map(.HttpCodeData.UsageData[].TimeStamp |= datestamp2epoch)
' <<< ${api_result}

ERROR

jq: error (at <stdin>:1): Cannot index number with string "HttpCodeData"

CodePudding user response：

Drop map as your document is an object, not an array. Then, to convert the timestamps to Unix epoch seconds, it suffices to apply fromdateiso8601:

jq '.HttpCodeData.UsageData[].TimeStamp |= fromdateiso8601' <<< "${api_result}"

{
  "DataInterval": 300,
  "EndTime": "2022-07-25T15:15:00Z",
  "HttpCodeData": {
    "UsageData": [
      {
        "TimeStamp": 1659063600,
        "Value": {
          "CodeProportionData": [
            {
              "Code": "404",
              "Count": 36,
              "Proportion": 0.022
            },
            {
              "Code": "502",
              "Count": 3,
              "Proportion": 0.002
            }
          ]
        }
      },
      {
        "TimeStamp": 1659063900,
        "Value": {
          "CodeProportionData": [
            {
              "Code": "404",
              "Count": 27,
              "Proportion": 0.015
            },
            {
              "Code": "502",
              "Count": 5,
              "Proportion": 0.002
            }
          ]
        }
      }
    ]
  },
  "StartTime": "2022-07-25T15:10:00Z"
}

Demo

Note: If you wanted to include also .StartTime and .EndTime, just list them along on the LHS:

(.StartTime, .HttpCodeData.UsageData[].TimeStamp, .EndTime) |= fromdateiso8601