deeply map object keys with JavaScript (lodash) https://stackoverflow.com/questions/35055731/how-to-deeply-map-object-keys-with-javascript-lodash

method1.js

_.mixin({
    'deepMapKeys': function (obj, fn) {

        var x = {};

        _.forOwn(obj, function(v, k) {
            if(_.isPlainObject(v))
                v = _.deepMapKeys(v, fn);
            x[fn(v, k)] = v;
        });

        return x;
    }
});

method2.js

_.mixin({
    deep: function (obj, mapper) {
        return mapper(_.mapValues(obj, function (v) {
            return _.isPlainObject(v) ? _.deep(v, mapper) : v;
        }));
    },
});

obj = _.deep(obj, function(x) {
    return _.mapKeys(x, function (val, key) {
        return key + '_hi';
    });
});

method3.js

_.mixin({
    deeply: function (map) {
        return function(obj, fn) {
            return map(_.mapValues(obj, function (v) {
                return _.isPlainObject(v) ? _.deeply(map)(v, fn) : v;
            }), fn);
        }
    },
});


obj = _.deeply(_.mapKeys)(obj, function (val, key) {
    return key + '_hi';
});

problem.js

var obj = { a: 2, b: { c: 2, d: { a: 3 } } };
_.deepMapKeys(obj, function (val, key) {
  return val + '_hi';
});
// => { a_hi: 2, b_hi: { c_hi: 2, d_hi: { a_hi: 3 } } }