Convert flat JSON file to hierarchical json data like flare.json [d3 example file]

Question

After a troublesome fight i almost figured how to convert a flat json file to a Hierarchical one. I didn\'t write the function by my own. I copied it from the below post.

Answer 1

var data = [
    { "state": "UP", "district": "Agra", "block": "IradatNagar","school":"APS","name":"A" },
    { "state": "UP", "district": "Agra", "block": "IradatNagar","school":"IPS","name":"B" },
    { "state": "UP", "district": "Agra", "block": "IradatNagar","school":"APS","name":"C" },
    { "state": "MP", "district": "Bhopal", "block": "chota_Bhopal","school":"DPS","name":"D" },
    { "state": "UP", "district": "Mathura", "block": "Farah","school":"HPS","name":"E" },
    { "state": "UP", "district": "Kanpur", "block": "Mania","school":"BPs","name":"F" },
    { "state": "UP", "district": "Agra", "block": "Arjun Nagar","school":"GPS","name":"G" }, 
    { "state": "MP", "district": "Gwalior", "block": "Surya Nagar","school":"DPS","name":"H" }
];

var newData = { name :"State", children : [] },
    levels = ["state","district","block","school"];

data.forEach(function(d){
    var depthCursor = newData.children;
    levels.forEach(function( property, depth )
    {
        var index;
        depthCursor.forEach(function(child,i)
        {
            if ( d[property] == child.name ) 
                index = i;
        });

        if ( isNaN(index) ) 
        {
            depthCursor.push({name : d[property], children : []});
            index = depthCursor.length - 1;
        }

        depthCursor = depthCursor[index].children;

        if ( depth === levels.length - 1 )
        {
            depthCursor.push({ name : d.name});
        }
    });
});

console.log(newData);

Answer 2

Updated to use a recursive method

This should work for n levels rather than just 2 or 3. You just need to specify which properties define which levels.

var data = [
    { "dep": "First Top", "name": "First child", "model": "value1", "size": "320" },
    { "dep": "First Top", "name": "First child", "model": "value2", "size": "320" },
    { "dep": "First Top", "name": "SECOND CHILD", "model": "value1", "size": "320" },
    { "dep": "Second Top", "name": "First Child", "model": "value1", "size": "320" }
];

var newData = { name :"root", children : [] },
    levels = ["dep","name"];

// For each data row, loop through the expected levels traversing the output tree
data.forEach(function(d){
    // Keep this as a reference to the current level
    var depthCursor = newData.children;
    // Go down one level at a time
    levels.forEach(function( property, depth ){

        // Look to see if a branch has already been created
        var index;
        depthCursor.forEach(function(child,i){
            if ( d[property] == child.name ) index = i;
        });
        // Add a branch if it isn't there
        if ( isNaN(index) ) {
            depthCursor.push({ name : d[property], children : []});
            index = depthCursor.length - 1;
        }
        // Now reference the new child array as we go deeper into the tree
        depthCursor = depthCursor[index].children;
        // This is a leaf, so add the last element to the specified branch
        if ( depth === levels.length - 1 ) depthCursor.push({ name : d.model, size : d.size });
    });
});