Convert Nested JSON to Flat JSON

Question

I am using javascript and I have nested json object getting from mongodb.

"abc": [
    {
      "a": "01AABCE2207R1Z5",
      "b": "Y",
      "c": [
        {
          "ca": "A",
          "cb": "AflJufPlFStqKBZ",
          "cc": "S008400"
         },
         {
          "cx": "A",
          "cy": "AflJufPlFStqKBZ",
          "cz": "S008400"
         }
        ]
     },

      {
      "a": "01AABCE2207R1Z5",
      "b": "Y",
      "c": [
        {
          "ca": "A",
          "cb": "AflJufPlFStqKBZ",
          "cc": "S008400"
         },
         {
          "cx": "A",
          "cy": "AflJufPlFStqKBZ",
          "cz": "S008400"
         }
        ]
     }
    ]

Above schema have fixed fields there will no changes in schema.

Now I want to make it as flat json array object and result should be like that. If c has multiple json object the it should create a new json object with the same a, b value

 [{
     "a": "01AABCE2207R1Z5",
     "b": "Y", 
     "ca": "A",
     "cb": "AflJufPlFStqKBZ",
     "cc": "S008400" 
    },
{
     "a": "01AABCE2207R1Z5",
     "b": "Y",  
     "cx": "A",
     "cy": "AflJufPlFStqKBZ",
     "cz": "S008400"
    },
    {
     "a": "01AABCE2207R1Z5",
     "b": "Y", 
     "ca": "A",
     "cb": "AflJufPlFStqKBZ",
     "cc": "S008400" 
    },
    {
     "a": "01AABCE2207R1Z5",
     "b": "Y",  
     "cx": "A",
     "cy": "AflJufPlFStqKBZ",
     "cz": "S008400"
    }
    ]

So, I want to know the fast and easy steps to make it flat. Please let me know the process and methods to solve this.

Thanks

You have not even tagged this with a language you want to do this in ... And you should have at least an approach you come up with yourself to show us. — CBroe, Jun 20 '17 at 09:13
I am using javascript @CBroe. and I tried by using `forloop` but when I m doing it with forloop its became a lengthy process. — Saurabh Sharma, Jun 20 '17 at 09:15
One loop over the main level items, and inside another loop that gets everything out of the `c` sub structure, places it on the same main level, afterwards remove the original `c` ... _"how hard can it be?"_ — CBroe, Jun 20 '17 at 09:18
main level `abc` can have multiple objects in array, then `c` have multiple json objects — Saurabh Sharma, Jun 20 '17 at 09:20

score 5 · Accepted Answer · answered Jun 20 '17 at 10:14

It is so easy to do this.

var flatArray = [];
var flatObject = {};

for (var index = 0; index < data.length; index++) {
  for (var prop in data[index]) {

    var value = data[index][prop];

    if (Array.isArray(value)) {
      for (var i = 0; i < value.length; i++) {
        for (var inProp in value[i]) {
          flatObject[inProp] = value[i][inProp];
        }
      }
    }else{
        flatObject[prop] = value;
    }
  }
  flatArray.push(flatObject);
}

console.log(flatArray);

data is your array.

score 0 · Answer 2 · edited Sep 08 '21 at 18:13

this will flat JSONObject even that includes JSONArray in it ...please use it ..will work

const flatJSONObject = r => {//flaten the Json in full depth
    const oc = ({}).constructor;
    const ac = ([]).constructor;
    var o={};
    if(r.constructor === oc) 
    {
          for (var k in r) {
            if ( r[k].constructor === oc) o = {...o,...flatJSONObject(value)}
            else if (  r[k].constructor === ac) r[k].forEach(e =>o = {...o,...flatJSONObject(e)});
            else o[k] =  r[k];
          } 
    }
    return o;
}

Convert Nested JSON to Flat JSON

2 Answers2

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