JSON to JSON transformation - Need to define a JOLT specification which will remove empty string, space element from a group array element.

Below example has two sets of array group records with " " empty string and a space.

Input example:

{
  "C1-RECORD": {
    "C1-ACTIONS": {
      "C1-MESSAGES": [
        {
          "C1-MSG-CODE": "UPT",
          "C1-MSG-DEFINITION": "Update task"
        },
        {
          "C1-MSG-CODE": "DEL",
          "C1-MSG-DEFINITION": "Delete task"
        },
        {
          "C1-MSG-CODE": " ",
          "C1-MSG-DEFINITION": " "
        },
        {
          "C1-MSG-CODE": " ",
          "C1-MSG-DEFINITION": " "
        }
      ]
    }
  }
}

JOLT Spec:

[
  {
    "operation": "shift",
    "spec": {
      "C1-RECORD": {
        "C1-ACTIONS": {
          "C1-MESSAGES": {
            "*": {
              "C1-MSG-CODE": "actions.messages[#2].msgCode",
              "C1-MSG-DEFINITION": "actions.messages[#2].msgDefinition"
            }
          }
        }
      }
    }
  }
]

Output:

{
  "actions" : {
    "messages" : [ {
      "msgCode" : "UPT",
      "msgDefinition" : "Update task"
    }, {
      "msgCode" : "DEL",
      "msgDefinition" : "Delete task"
    }, {
      "msgCode" : " ",
      "msgDefinition" : " "
    }, {
      "msgCode" : " ",
      "msgDefinition" : " "
    } ]
  }
}

The output is return array records with " " empty string and a space.

Need a JOLT transformation specs to remove the msgCode and msgDefinition fields without any value and with empty string " " and space.

The expected output should be:

> {
>   "actions": {
>     "messages": [
>       {
>         "msgCode": "UPT",
>         "msgDefinition": "Update task"
>       },
>       {
>         "msgCode": "DEL",
>         "msgDefinition": "Delete task"
>       }
>     ]
>   }
> }

I tried the below JOLT spec:

[
  {
    "operation": "shift",
    "spec": {
      "C1-RECORD": {
        "C1-ACTIONS": {
          "C1-MESSAGES": {
            "*": {
              "C1-MSG-CODE": {
                " ": null,
                "*": {
                  "$": "actions.messages.msgCode"
                }
              },
              "C1-MSG-DEFINITION": {
                " ": null,
                "*": {
                  "$": "actions.messages.msgDefinition"
                }
              }
            }
          }
        }
      }
    }
  }
]

but the output came out as below which is not the right format:

{
  "actions" : {
    "messages" : {
      "msgCode" : [ "UPT", "DEL" ],
      "msgDefinition" : [ "Update task", "Delete task" ]
    }
  }
}

Trying to search for solution but not a lot out there.

Appreciate any help.

Thanks

CodePudding user response：

You can use this spec:

[
  {
    "operation": "shift",
    "spec": {
      "*": {
        "*": {
          "*": {
            "*": {
              "C1-MSG-CODE": {
                " ": null,
                "*": {
                  "@1": "actions.messages[&3].msgCode"
                }
              },
              "C1-MSG-DEFINITION": {
                " ": null,
                "*": {
                  "@1": "actions.messages[&3].msgDefinition"
                }
              }
            }
          }
        }
      }
    }
  }
]

CodePudding user response：

You can just prepend your attributes with [#4] in order to distinguish the values at the level of the indexes of "C1-MESSAGES" array by going up the tree 4 level throuh traversing one column and three opening curly braces as that # wildcard stays on the right hand side of the expression such as

[
  {
    "operation": "shift",
    "spec": {
      "C1-RECORD": {
        "C1-ACTIONS": {
          "C1-MESSAGES": {
            "*": {
              "C1-MSG-CODE": {
                " ": null,
                "*": {
                  "$": "actions.messages[#4].msgCode"
                }
              },
              "C1-MSG-DEFINITION": {
                " ": null,
                "*": {
                  "$": "actions.messages[#4].msgDefinition"
                }
              }
            }
          }
        }
      }
    }
  }
]