1var result1 = [
2    {id:1, name:'Sandra', type:'user', username:'sandra'},
3    {id:2, name:'John', type:'admin', username:'johnny2'},
4    {id:3, name:'Peter', type:'user', username:'pete'},
5    {id:4, name:'Bobby', type:'user', username:'be_bob'}
6];
7
8var result2 = [
9    {id:2, name:'John', email:'johnny@example.com'},
10    {id:4, name:'Bobby', email:'bobby@example.com'}
11];
12
13var props = ['id', 'name'];
14
15var result = result1.filter(function(o1){
16    // filter out (!) items in result2
17    return !result2.some(function(o2){
18        return o1.id === o2.id;          // assumes unique id
19    });
20}).map(function(o){
21    // use reduce to make objects with only the required properties
22    // and map to apply this to the filtered array as a whole
23    return props.reduce(function(newo, name){
24        newo[name] = o[name];
25        return newo;
26    }, {});
27});
28
29document.body.innerHTML = '<pre>' + JSON.stringify(result, null, 4) +
30        '</pre>';