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Got a null object in array

See original GitHub issue

Hi everyone,

I would like to select themes that have an itemsarray.

Data origin :

{
  "themes": [
    {
      "id": "122jj23164-8202-4da2-901e-1237f1236",
      "name": "Push Products N1"
    },
    {
      "id": "123fklj786-8202-4da2-901e-87123873",
      "name": "Push Products N2",
      "items": {
        "item": [
          {
            "id": 19812,
             "attribute": [
                {
                  "name": "second-id",
                  "value": {
                    "content": 19812
                  }
                },
                {
                  "name": "wording",
                  "value": {
                    "content": "A product"
                  }
                }
              ]
          },
          {
            "id": 87613,
            "attribute": [
              {
                "name": "second-id",
                "value": {
                  "content": 87613
                }
              },
              {
                "name": "wording",
                "value": {
                  "content": "Sample"
                }
              }
            ]
          }
        ]
      }
    }
  ]
}

Jolt :

[
  {
    "operation": "shift",
    "spec": {
      "themes": {
        "*": {
          "items": {
            "@(1,id)": "themes[&2].id",
            "@(1,name)": "themes[&2].name",
            "item": {
              "*": {
                "id": "themes[&4].products[].id",
                "attribute": {
                  "*": {
                    "value": {
                      "content": "themes[&7].products[&4].@(2,name)"
                    }
                  }
                }
              },
              "id": "themes[&3].products[&3].id",
              "attribute": {
                "*": {
                  "value": {
                    "content": "themes[&6].products[&6].@(2,name)"
                  }
                }
              }
            }
          }
        }
      }
    }
  }
]

I don’t understand why I got a null at the first index on my themes array.

{
  "themes" : [ null, {
    "id" : "123fklj786-8202-4da2-901e-87123873",
    "name" : "Push Products N2",
    "products" : [ {
      "id" : 19812,
      "second-id" : 19812,
      "wording" : "A product"
    }, {
      "id" : 87613,
      "second-id" : 87613,
      "wording" : "Sample"
    } ]
  } ]
}

Issue Analytics

State:
Created 6 years ago
Comments:6

Top GitHub Comments

2reactions

milosimpsoncommented, May 4, 2017

You need to do two shifts.

First shift only passes thru elements of the “theme” array that are “valid”, where valid means I think means “it has at least one element of in the item.items array”.

Then do the rest of the transform as normal.

[
  {
    "operation": "shift",
    "spec": {
      "themes": {
        "*": { // visit each item in themes array
          "items": {
            "item": {
              "0": {
                // if we matched to here it menas this element
                // of the themes array has "items.item[]" with 
                // at leat one element.
                // Thus this "theme" is valid, and we will copy
                // it across.
                "@3": "temp[]"
              }
            }
          }
        }
      }
    }
  },
  {
    "operation": "shift",
    "spec": {
      "temp": {
        "*": {
          "id": "themes[&1].id",
          "name": "themes[&1].name",
          "items": {
            "item": {
              "*": {
                "id": "themes[&4].products[&1].id",
                "attribute": {
                  "*": {
                    "value": {
                      "content": "themes[&7].products[&4].@(2,name)"
                    }
                  }
                }
              },
              "id": "themes[&3].products[&2].id",
              "attribute": {
                "*": {
                  "value": {
                    "content": "themes[&6].products[&6].@(2,name)"
                  }
                }
              }
            }
          }
        }
      }
    }
  }
]

0reactions

Matsa59commented, May 4, 2017

Yes exactly. I was thinking JOLT do it natively by removing null object in array

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