Node.js mongodb批量插入

i'm kinda new to node.js and mongo and i'm having a little problem. I can't bulk insert documents into mongodb using ajax on client and nodejs/express on server. Here is my client code:

<button class="btn>Send</button>
data = {'test':'test1','test':'2','test':'test1','test':'test2','test':'test1','test':'test2'}

        $(".btn").click(function(){
            $.ajax({
                url: 'http://localhost:8000/2',
                type: 'post',
                dataType: 'json',
                data: data 
            });
        });

And here is my route handler in node:

app.post('/2', function(req, res){
var docs = [];
 for(var i = 0; i < 10000; i++) {
     docs[i] = req.body;
 }

 db.collection('test', function(err, collection){
    collection.insert(docs, function(err, result) {
        if (!err) {
            console.log(result);
            res.end();
        } else {
            throw err
        }
    })
 });

})

I'm getting data nicely with console.log(docs), but my test collection is empty. What am i missing? Thanks

 app.post('/2', function(req, res){
  var docs = req.body.data; // ur json data is now in node end        
  var i=0;
  var bulk = test.collection.initializeUnorderedBulkOp();  // test is the        model name. I used mongoose  
  // now using loop insert all json data inside bulk variable   
  for (i = 0; i < docs.length; i += 1) {
     bulk.insert(docs[i]);
  }

  //after insertion finished u might need node-async module, to insert first 
  //then asynchronously execute bulk 
   bulk.execute(function (errx) {
         if (errx) { return next(errx); }
                     console.log('Success');
            });
 })

you need to define test schema and test model correctly. For further details you can read following links https://docs.mongodb.com/manual/reference/method/Bulk.insert/