[{ 'index':0 }.., ]

[{ 'source':{'index':0},
   'target':{'index':1}},
 { 'source':{...},
   'target':{...}}
                ...]

{0:[1,2,3]}

var Node = 1;
var res = [];

for(var index in edges) {
    if (edges[index].source == Node) res.push(edges[index].target);
}

var ret = {};
ret[Node] = res;

var res = {};

for(var node in nodes) {
    var rel = [];

    for(var edge in edges) {
        if (edges[edge].source == nodes[node].index) rel.push(edges[edge].target);
    }

    res[nodes[node].index] = rel;
}

var res = {};

for(var edge in edges) {
    if (!res.hasOwnProperty(res[edges[edge].source].toString())) {
        res[edges[edge].source] = [];
    }

    res[edges[edge].source].push(edges[edge].target);
}