Upload to nginx with crypto AES

[Duskfall]

I have implemented an nginx approach to upload files but i want to add encryption prior to uploading now.
My jquery upload initialization is as follows:

$('#fileupload').fileupload({
maxRetries: 15,
retryTimeout: 1000,
dataType: 'text',
maxFileSize: 50 * 1024 * 1024 * 1024,
//upload 5 MB at a time
maxChunkSize: 5 * 1024 * 1024,
//acceptFileTypes: /(.|/)(gif|jpe?g|png)$/i,
multipart: false,
beforeSend: function(e, files, index, xhr, handler, callback) {
var chrome, context, device, file, filename, filesize, ios, sessionID;

        // Retrieve the file that is about to be sent to nginx
        file = files.files[0];
        // Collect some basic file information
        filename = file.name;
        filesize = file.size;
        // Grab the context (table row) for this upload

        context = files.context[0];

        encryptFiles(files.files, function () {
              console.log(files.files)
              files.files = encrypted;
              //data.submit();
        });
        // Set uploadedBytes on the context to ensure that if this upload was
        // resumed, it will continue from where it left off.
        $(context).attr("uploadedBytes", files.uploadedBytes);
        // Set the required headers for the nginx upload module
        e.setRequestHeader("Session-ID", sessionID);
        var ext = false;
        if (filename.lastIndexOf(".") == (filename.length-4) || filename.lastIndexOf(".") == (filename.length-5) ) {
          ext = true;
        }
        if (!ext) {
          e.setRequestHeader("Content-Type", "text/plain");
        }
        e.setRequestHeader("X-Requested-With", "XMLHttpRequest");

        device = navigator.userAgent.toLowerCase();
        ios = device.match(/(iphone|ipod|ipad)/);
        chrome = device.match(/crios/);

        if (ios && !chrome) {
          e.setRequestHeader("Cache-Control", "no-cache");
        }
    }

});

I have tried to use as you said somewhere in the add option

add: function (e, data) {
encryptFiles(data.files, function () {
data.submit();
});
}

but the template doesnt work. It doesnt read the context and upload doesnt proceed because the context which is the tr of the table is 0

my encryptFiles function is :

var encryptFiles = function (files, callback) {
var reader = new FileReader();
var file = files[0];
var blob = file.slice(0, file.size);
var key = "testkey";
reader.readAsBinaryString(blob);
reader.onload = fileonload;
function fileonload(event) {
var result = event.target.result;
var encrypted = CryptoJS.AES.encrypt(result, CryptoJS.enc.Base64.parse(key));
callback();
}
}

encryption is as normal and when i alert the encrypted value i get the base64 thing.
I dont know how to proceed from there.
How can i pass the encrypted data to the library so that it sends the encrypted data instead of the unencrypted when file was added.

[blueimp]

I recommend you to make use of the processing queue for encryption.
There is no documentation yet, so you have to analyse the source code until issue #2606 is closed.