get hierarchical data from json

Question

var oTeamHierarchyJson = [
            {
                "Key": "10011",
                "Name": "A",                
                "Job Title": "VP",                
                "children": "C",
                "Parent": "1000",
                "Level": "1"
            },
            {
                "Key": "10012",
                "Name": "B",                
                "Job Title": "VP",                
                "children": "D",
                "Parent": "1001",
                "Level": "1"
            },
            {
                "Key": "10013",
                "Name": "C",               
                "Job Title": "GM",                
                "children": "E",
                "Parent": "10011",
                "Level": "2"
            },
            {
                "Key": "10014",
                "Name": "D",
                "Job Title": "MP",                
                "children": "F",
                "Parent": "10013",
                "Level": "3"
            }
        ];

I want to write a function which will take a key and get all it's child recursively.

function filterJSONData(currentKey) {
      //return all children recursively
}

for 10011 - return 10013, 10014

Answer 1

function getKeys(key) {
    var keys = [];
    # We all the keys for which the parent is key passed in as argument
    oTeamHierarchyJson.forEach(function(currentItem) {
        if (currentItem.Parent === key) {
            keys.push(currentItem.Key);
        }
    });

    # For eavery matched key, call getKeys recursively and flatten the result
    return [].concat.apply([key], keys.map(getKeys));
}

console.log(getKeys("10011"));
# [ '10011', '10013', '10014' ]

Answer 2

The data structure saves only the parent relation, not the child relation, which is not really suitable for traversal. There are two ways to circumvent this shortcoming:

1. Process the array to have each note refer to all of its children
2. Introduce a helper function which returns all children of a node

Afterwards, it is much easier to find all successors of a given node recursively.

Answer 3

You can build a tree from your flat data list. Following code adds recursively a property children and fills it with the children of the each node. see http://jsfiddle.net/jeromerg/234jk/

buildTree = function(array, nodeKey) {

    // getNode
    var node = null;
    for(var i=0; i<array.length; i++) {
        if(array[i].Key == nodeKey) {
             node = array[i];
            break;
        }
    }

    if(node === null) {
        null;   
    }

    // fill new children property
    node.childen = [];
    for(var i=0; i<array.length; i++) {
        if(array[i].Parent == nodeKey) {
            alert("COUCOU");
            node.childen.push(array[i]);

            // recursive call!
            buildTree(array, array[i].Key);
        }
    }

    return node;

}

var result = buildTree(oTeamHierarchyJson, 10011);

alert(JSON.stringify(result));