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Javascript: How to encrypt a zip file with RSA

I'm using Cryptico to handle RSA encryption for chat but I'm running into trouble trying to encrypt a zip file after construction. I see the constructed file in the console. The console shows an encrypted string of the file but returns blank after decryption in the console.
Note: my decryption method works properly with text and base64
$(document).on("change", "#chatImage", function() {
var rid = $(this).closest(".chat").data("id");
var files = this.files;
var zip = new JSZip();
for (var i = 0; i < files.length; i += 1) {
var file = files[i];
zip.file(file.name, file);
console.log("added", file.name);
// console.log(file);
}
var eImgArray = {};
$.ajax({
url : ajax_object.ajax_url,
type : 'post',
data : {
action: 'get_room_member_keys',
rid : rid,
},
beforeSend: function() {
},
success: function(html) {
var pubKeys = $.parseJSON(html);
$.each( pubKeys, function( key, value ) {
var imgEncrypt = cryptico.encrypt(file, value);
var imgSrc = imgEncrypt.cipher;
eImgArray[key] = imgSrc;
});
var strImgArray = JSON.stringify(eImgArray);
$("#chatFormCont input[name=image_data]").val(strImgArray);
var foo = $("#chatFormCont input[name=image_data]").val();
// console.log(foo);
},
});
zip.generateAsync({type: "blob"}).then(function(content) {
function show_all_images(relpath, file) {
if (file.dir) {
return file.forEach(show_all_images);
}
var img = $("#chatImagePreview");
file.async("blob").then(function(blob) {
var src = window.URL.createObjectURL(blob);
img.attr("src", src);
});
}
new JSZip.loadAsync(content).then(zip => zip.forEach(show_all_images));
});
});

How to write a callback for FileReader?

I'm trying to upload multiple attachments.
First I'm getting attachments from user interface, then I'm converting them into JSON , then I need to make a server call.
In this I'm using FileReader.
//showing ajax loader
component.set("v.showLoadingSpinner", true);
//getting attached files
var files = component.find("fileId").get("v.files");
var details = {}; //JS Object need to send server
details.files = [];
for (var i = 0; i < files.length; i++)
{
(function(file) {
var name = file.name;
var reader = new FileReader();
reader.fName = files[i]['name'];
reader.fType = files[i]['type'];
reader.i = i;
reader.onload = function(e) {
var fileContents = reader.result;
var base64 = 'base64,';
var dataStart = fileContents.indexOf(base64) + base64.length;
fileContents = fileContents.substring(dataStart);
var startPosition = 0;
var endPosition = Math.min(fileContents.length, startPosition + 750000);
var getchunk = fileContents.substring(startPosition, endPosition);
var fDetails = {};
fDetails.fileName = reader.fName;
fDetails.base64Data = encodeURIComponent(getchunk);
fDetails.contentType = reader.fType;
details.files.push(fDetails);
}
reader.readAsDataURL(file);
})(files[i]);
// I want to make a server call here with data in "details" object.
console.log(details);
But I'm not getting data in above console log.
Please help me to achieve this.

You can use promises :
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise
https://davidwalsh.name/promises
https://developers.google.com/web/fundamentals/primers/promises
Also jQuery provide $.when() function :
https://api.jquery.com/jquery.when/
And with promisejs you can do something like this :
function readJSON(filename){
return new Promise(function (fulfill, reject){
readFile(filename, 'utf8').done(function (res){
try {
fulfill(JSON.parse(res));
} catch (ex) {
reject(ex);
}
}, reject);
});
}

Safari browsers sends blob/datauri as string in Node.js

I am trying to receive the file sent through AJAX. What's happening is that when the file sent using Chrome/Firefox the file goes to req.files but when it was sent using Safari, the file goes to req.params. The application treat the file as a string "[Object blob]". Thanks.
Sending userdata through ajax.
updatePartnerProfile: function(obj){
var parentObj = this;
var target = $(obj.target);
var parent = target.closest('#editPartnerDetailsForm');
var logoImg = parent.find('.cropped');
var companyLogoBase64 = logoImg.find('.croppedImage').attr('src');
var companyLogo = util.dataURItoBlob(companyLogoBase64);
var userData = new FormData();
userData.append('token', parentObj.token);
userData.append('companyLogo', companyLogo);
$.ajax({
type: 'POST',
url: parentObj.serverUrl + 'api/admin/update/organization/' + parentObj.partnerId,
processData: false,
contentType: false,
cache: false,
data: userData,
success: function(data){
//todo
}
},
error: function(err){
console.log(err);
}
});
},
dataURItoBlob : function(dataURI) {
// convert base64/URLEncoded data component to raw binary data held in a string
if (!_.isUndefined(dataURI)){
var byteString;
if (dataURI.split(',')[0].indexOf('base64') >= 0)
byteString = atob(dataURI.split(',')[1]);
else
byteString = unescape(dataURI.split(',')[1]);
// separate out the mime component
var mimeString = dataURI.split(',')[0].split(':')[1].split(';')[0]
// write the bytes of the string to a typed array
var ia = new Uint8Array(byteString.length);
for (var i = 0; i < byteString.length; i++) {
ia[i] = byteString.charCodeAt(i);
}
return new Blob([ia], {type:mimeString});
} else {
return null;
}
}
Am I missing something in the code?

Well, as per this question, you need to be using the buffer property of ia, not just [ia]. Instead of
return new Blob([ia], {type:mimeString});
try
return new Blob([ia.buffer], {type:mimeString});

Difficulty in loading multiple images in a list view served by multiple xml files

I am developing a html application for Android and I am trying to load images in a list view. Data specific to list items is being served by multiple xml files. I am using ajax to load xml files and populate the list items. Problem I am facing here is that there are 164 list items. Hence, 164 images and 10 xml files to load. my loader function exhausts after two iterations. It does read the xml files but it's unable to dynamically create list items and populate them with images after two iterations. I believe it's due to stack limitations. I can't think of alternate solution. If somebody could suggest an alternate solution that will be highly appreciated. Below is my loader function. It's a recursive function:
function loadChannels() {
$.ajax({
type: "GET",
url: curURL,
dataType: "xml",
error: function(){ console.log('Error Loading Channel XML'); },
success: function(nXml) {
var noOfItems = parseInt($($(nXml).find('total_items')[0]).text(), 10);
var startIdx = parseInt($($(nXml).find('item_startidx')[0]).text(), 10);
var allItems = $(nXml).find('item');
$(allItems).each(function() {
var obj = $("<li><span id='cont-thumb'></span><span id='cont-name'></span></li>");
$("#content-scroller ul").append($(obj));
var imgURL = $($(this).find('item_image')[0]).text();
var contThumb = $(obj).children()[0];
$(contThumb).css("background-image", 'url('+imgURL+')');
var name = $($(this).find('name')[0]).text();
var contName = $(obj).children()[1];
$(contName).text(name).css('text-align', 'center');
var url = $($(this).find('link')[0]).text();
$(obj).data('item_link', url);
$(obj).bind('click', onJPContSelected);
});
if(startIdx+allItems.length < noOfItems){
var newIdx = new Number(startIdx+allItems.length);
var tokens = curURL.split("/");
tokens[tokens.length-2] = newIdx.toString(10);
curURL = "http:/";
for(var i=2; i<tokens.length; i++)
curURL = curURL + "/" + tokens[i];
loadChannels();
}
}
});
}

try to remove the recursion with an outer loop - something like that:
function loadChannels(){
var stopFlag = false;
// request the pages one after another till done
while(!stopFlag)
{
$.ajax({
type: "GET",
url: curURL,
dataType: "xml",
error: function(){
console.log('Error Loading Channel XML');
errorFlaf = true;
},
success: function(nXml) {
var noOfItems = parseInt($($(nXml).find('total_items')[0]).text(), 10);
var startIdx = parseInt($($(nXml).find('item_startidx')[0]).text(), 10);
var allItems = $(nXml).find('item');
$(allItems).each(function() {
var obj = $("<li><span id='cont-thumb'></span><span id='cont-name'></span></li>");
$("#content-scroller ul").append($(obj));
var imgURL = $($(this).find('item_image')[0]).text();
var contThumb = $(obj).children()[0];
$(contThumb).css("background-image", 'url('+imgURL+')');
var name = $($(this).find('name')[0]).text();
var contName = $(obj).children()[1];
$(contName).text(name).css('text-align', 'center');
var url = $($(this).find('link')[0]).text();
$(obj).data('item_link', url);
$(obj).bind('click', onJPContSelected);
});
if(startIdx+allItems.length < noOfItems){
var newIdx = new Number(startIdx+allItems.length);
var tokens = curURL.split("/");
tokens[tokens.length-2] = newIdx.toString(10);
curURL = "http:/";
for(var i=2; i<tokens.length; i++)
curURL = curURL + "/" + tokens[i];
// lets disable the recursion
// loadChannels();
}
else {
stopFlag = true;
}
}
});
}
}

Object has no method "open" error when using indexedDB

I'm trying to build a small class-like container that will make it a little cleaner to load and store data from the HTML5 IndexedDB. To be honest this is the first time I've ever played with this feature, so my issue could be trivial.
I'm basing my code off of this tutorial:
http://www.html5rocks.com/en/tutorials/indexeddb/todo/
function DBDictionary()
{
this.Holder = {};
this.Entries = new Array();
this.Opened = false;
this.v = "1.0";
this.Holder.indexedDB = window.indexedDB || window.webkitIndexedDB || window.mozIndexedDB;
if ('webkitIndexedDB' in window)
{
window.IDBTransaction = window.webkitIDBTransaction;
window.IDBKeyRange = window.webkitIDBKeyRange;
}
this.Holder.indexedDB = {};
this.Holder.indexedDB.db = null;
this.Holder.indexedDB.onerror = function(e)
{
console.log(e);
};
this.DownloadDB = function()
{
if(this.Opened) return;
var request = this.Holder.indexedDB.open("Storage");
request.onsuccess = function(e)
{
this.Holder.indexedDB.db = e.target.result;
var db = this.Holder.indexedDB.db;
// We can only create Object stores in a setVersion transaction;
if (v!= db.version)
{
var setVrequest = db.setVersion(v);
// onsuccess is the only place we can create Object Stores
setVrequest.onerror = this.Holder.indexedDB.onerror;
setVrequest.onsuccess = function(e)
{
if(db.objectStoreNames.contains("Storage")) db.deleteObjectStore("Storage");
var store = db.createObjectStore("Storage", {keyPath: "Key"});
this.PopulateAll();
};
}
else
{
this.PopulateAll();
}
};
request.onerror = this.Holder.indexedDB.onerror;
};
this.UploadDB = function()
{
this.DeleteAll();
this.SaveAll();
};
this.DeleteAll = function()
{
var db = this.Holder.indexedDB.db;
var trans = db.transaction(["Storage"], IDBTransaction.READ_WRITE);
var store = trans.objectStore("Storage");
Entries.forEach(function(element, index, array)
{
var request = store.delete(index);
request.onerror = function(e)
{
console.log("Error Deleting: ", e);
};
});
};
this.PopulateAll = function()
{
var db = this.Holder.indexedDB.db;
var trans = db.transaction(["Storage"], IDBTransaction.READ_WRITE);
var store = trans.objectStore("Storage");
// Get everything in the store;
var keyRange = IDBKeyRange.lowerBound(0);
var cursorRequest = store.openCursor(keyRange);
cursorRequest.onsuccess = function(e)
{
var result = e.target.result;
//No more results to load
if(!!result == false)
{
if(!this.Opened) this.Opened = true;
return;
}
this.Entries[result.Key] = result.Value;
result.continue();
};
cursorRequest.onerror = this.Holder.indexedDB.onerror;
};
this.SaveAll = function()
{
var db = this.Holder.indexedDB.db;
var trans = db.transaction(["Storage"], IDBTransaction.READ_WRITE);
var store = trans.objectStore("Storage");
Entries.forEach(function(element, index, array)
{
var data = {
"Key": index,
"Value": element,
"timeStamp": new Date().getTime()
};
var request = store.put(data);
request.onerror = function(e) {
console.log("Error Adding: ", e);
};
});
};
}
function main()
{
var dictionary = new DBDictionary();
dictionary.DownloadDB();
dictionary.Entries["hello"] = "world";
alert(dictionary.Entries["hello"]);
}
$(document).ready(main);
My desired implemented state should look something like this:
function main()
{
var dictionary = new DBDictionary();
dictionary.DownloadDB();
dictionary.Entries["hello"] = "world";
alert(dictionary.Entries["hello"]);
}
$(document).ready(main);
What this should do is download the data from the browser's IndexedDB object and store them into the object-housed array Entries. When I want to store the value of Entires back into the DB, I would call dictionary.UploadDB();
However, I'm getting the single javascript error: Uncaught TypeError: Object # has no method 'open'. I'm pretty much at a loss as to what I'm doing wrong. Can anyone offer me some tips?

Do a typeof check and console.log the this.Holder.indexedDB object to inspect the prototype. Does it inherit the IDBDatabase prototype? If it does, the open method would be available to you.
If your window.indexedDB did fire the on success callback, e.target.result would be the correct way to access the newly opened database via the event object. But the fact that you're not getting that far suggests that your this.Holder.indexedDB object is not actually an instance of an IDBDatabase.
EDIT: Yes, this is exactly your issue. If you console.log the this.holder.indexedDB object you get an object that looks like {"db":null}.
Swap this.Holder.indexedDB for window.webkitIndexedDB at your open invocation and you'll see that 'world' alert pops. JSFiddle here.