Обработка необязательных массивов с помощью jq

Question

Я получаю этот json файл, в котором перечислены одна или несколько записей. Когда имеется несколько записей, записи помещаются в массив. В противном случае нет массива. Я пытаюсь извлечь ключ сеанса из записей с помощью jq. Есть ли общий c способ сопоставить оба случая:

Пример № 1: сообщение с несколькими записями:

{
  "message": {
    "header": {
      "response": {
        "result": "SUCCESS",
        "gsbStatus": "PRIMARY"
      }
    },
    "body": {
      "bodyContent": {
        "type": "history:lstmeetingusageHistoryResponse",
        "meetingUsageHistory": [
          {
            "sessionKey": "1263859083",
            "meetingUUID": "603f5595dc8e4c7a9c2esdfsdf494cfae91815",
            "confName": "sdfsdf setup for Dsdfdf alerts",
            "meetingStartTime": "07/09/2020 14:00:17",
            "meetingEndTime": "07/09/2020 15:01:53",
            "duration": "62",
            "timezone": "GMT-05:00, Central (Chicago)",
            "timeZoneID": "7",
            "timeZoneWithDST": "Chicago (Central Daylight Time, GMT-05:00)",
            "trackingCode": null,
            "meetingType": "PRO",
            "hostWebExID": "conferenceroom01@abc.com",
            "hostName": "test Tech",
            "hostEmail": "conferenceroom01@abc.com",
            "totalCallInMinutes": "0",
            "totalPeopleMinutes": "192",
            "totalCallInTollfreeMinutes": "0",
            "totalCallOutDomestic": "0",
            "totalCallOutInternational": "0",
            "totalCallOutInternal": "0",
            "totalCallInInternational": "0",
            "tollCallInInternational": "0",
            "tollfreeCallInInternational": "0",
            "totalVoipMinutes": "192",
            "userID": "544798712",
            "totalParticipants": "4",
            "totalParticipantsVoip": "4",
            "totalParticipantsCallIn": "0",
            "totalParticipantsCallOut": "0",
            "confID": "166058947180001507",
            "peakAttendee": "4",
            "assistService": null
          },
          {
            "sessionKey": "623922696",
            "meetingUUID": "503dsfsdfsdfd4280e4a452e03b9c75dce0f26",
            "confName": "test Tech's Personal Room",
            "meetingStartTime": "06/24/2020 19:21:57",
            "meetingEndTime": "06/24/2020 20:11:42",
            "duration": "50",
            "timezone": "GMT-05:00, Central (Chicago)",
            "timeZoneID": "7",
            "timeZoneWithDST": "Chicago (Central Daylight Time, GMT-05:00)",
            "trackingCode": null,
            "meetingType": "PRO",
            "hostWebExID": "conferenceroom01@abc.com",
            "hostName": "test Tech",
            "hostEmail": "conferenceroom01@abc.com",
            "totalCallInMinutes": "0",
            "totalPeopleMinutes": "100",
            "totalCallInTollfreeMinutes": "0",
            "totalCallOutDomestic": "0",
            "totalCallOutInternational": "0",
            "totalCallOutInternal": "0",
            "totalCallInInternational": "0",
            "tollCallInInternational": "0",
            "tollfreeCallInInternational": "0",
            "totalVoipMinutes": "100",
            "userID": "544798712",
            "totalParticipants": "2",
            "totalParticipantsVoip": "2",
            "totalParticipantsCallIn": "0",
            "totalParticipantsCallOut": "0",
            "confID": "164945117836245416",
            "peakAttendee": "2",
            "assistService": null
          }
        ],
        "matchingRecords": {
          "total": "2",
          "returned": "2",
          "startFrom": "1"
        }
      }
    }
  }
}

Пример № 2: сообщение с одной записью:

{
  "message": {
    "header": {
      "response": {
        "result": "SUCCESS",
        "gsbStatus": "PRIMARY"
      }
    },
    "body": {
      "bodyContent": {
        "type": "history:lstmeetingusageHistoryResponse",
        "meetingUsageHistory": {
          "sessionKey": "297115075",
          "meetingUUID": "sdsadfdsfsfsfdsfsdf",
          "confName": "abc's Personal Room",
          "meetingStartTime": "07/09/2020 20:58:37",
          "meetingEndTime": "07/09/2020 22:38:15",
          "duration": "100",
          "timezone": "GMT-05:00, Central (Chicago)",
          "timeZoneID": "7",
          "timeZoneWithDST": "Chicago (Central Daylight Time, GMT-05:00)",
          "trackingCode": null,
          "meetingType": "PRO",
          "hostWebExID": "asdsad@abc.com",
          "hostName": "asdasdasdasd",
          "hostEmail": "asdsad@abc.com",
          "totalCallInMinutes": "0",
          "totalPeopleMinutes": "197",
          "totalCallInTollfreeMinutes": "0",
          "totalCallOutDomestic": "0",
          "totalCallOutInternational": "0",
          "totalCallOutInternal": "0",
          "totalCallInInternational": "0",
          "tollCallInInternational": "0",
          "tollfreeCallInInternational": "0",
          "totalVoipMinutes": "197",
          "userID": "487886288",
          "totalParticipants": "3",
          "totalParticipantsVoip": "3",
          "totalParticipantsCallIn": "0",
          "totalParticipantsCallOut": "0",
          "confID": "166305919935739955",
          "peakAttendee": "2",
          "assistService": null
        },
        "matchingRecords": {
          "total": "1",
          "returned": "1",
          "startFrom": "1"
        }
      }
    }
  }
}

Спасибо

Answer 1

Если допустимо распечатать все значения sessionKey, то, вероятно, самым простым будет:

.. | objects | select(has("sessionKey")) | .sessionKey

В противном случае вы можете использовать подход if ... then ... else ... end.