Question 323191 in Json Question posted in
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Json – How to check if an item exists in an array?

Here is a sample input JSON with an array and an item to find:

Input :

{
  "numbers": [
    "1234",
    "9999",
    "0123",
    "2311",
    "9911",
    "5410"
  ],
  "number": "9999"
}

Output :

{
  "numberExists": "true"
}

Both the fields are dynamic and I cannot hard-code anything.

Tags:

2

Answers


  1. 0

    The solution is based on similar post answered by @barbaros Özhan: Jolt Transform – Filter Array Where Fields equal

    [
  {
    "operation": "shift",
    "spec": {
      "number": {
        "$": "@(1)"
      },
      "numbers": {
        "*": {
          "*": {
            "$": "&1"
          }
        }
      }
    }
  }
,
  {
    "operation": "shift",
    "spec": {
      "*": {
        "*": {
          "number": {
            "#true": "numberExists"
          }
        }
      }
    }
   }
   ,
  {
    "operation": "default",
    "spec": {
      "numberExists": "false"
    }
  }


]
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  2. 0

    You might use the following transformation as an alternative to my previous solution which is presented within the other answer :

    [
  { // match the attribute of the object and components of the array
    "operation": "shift",
    "spec": {
      "numbe*": {
        "$": "@0",    // pick up from the attribute of the object
        "*": {
          "$": "@0[]" // pick up from the components of the array
        }
      }
    }
  },
  { // determine whether exists a match
    "operation": "modify-overwrite-beta",
    "spec": {
      "*": "=size"
    }
  },
  { // check out for the size value of 2 to show up the existence
    "operation": "shift",
    "spec": {
      "*": {
        "2": {
          "#true": "numberExists"
        }
      }
    }
  }
]

    Another smart, even shorter solution might be

    [
  {
    "operation": "shift",
    "spec": {
      "numbe*": {
        "$": "@0",
        "*": {
          "#true": "@0"
        }
      }
    }
  },
  {
    "operation": "shift",
    "spec": {
      "*": {
        "0": {
          "@": "numberExists"
        }
      }
    }
  }
]

    Btw, if returning the else case matters(unlike the the current question’s text), then you might add

      ,
  {
    "operation": "default",
    "spec": {
      "numberExists": "false"
    }
  }

    to the end of these transformations as presented in the other answer as well.

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