Non-ajax post using Dropzone.js - javascript

I'm wondering if there's any way to make Dropzone.js (http://dropzonejs.com) work with a standard browser POST instead of AJAX.
Some way to inject the inputs type=file in the DOM right before submit maybe?

No. You cannot manually set the value of a <input type='file'> for security reasons. When you use Javascript drag and drop features you're surpassing the file input altogether. Once a file is fetched from the user's computer the only way to submit the file to the server is via AJAX.
Workarounds: You could instead serialize the file or otherwise stringify it and append it to the form as a string, and then unserialize it on the server side.
var base64Image;
var reader = new FileReader();
reader.addEventListener("load", function () {
base64Image = reader.result;
// append the base64 encoded image to a form and submit
}, false);
reader.readAsDataURL(file);
Perhaps you're using dropzone.js because file inputs are ugly and hard to style? If that is the case, this Dropzone.js alternative may work for you. It allows you to create custom styled inputs that can be submitted with a form. It supports drag and drop too, but with drag and drop you cannot submit the form the way you want. Disclaimer: I am author of aforementioned library.

So, if I understood correctly you want to append some data (input=file) before submit your form which has dropzone activated, right?
If so, I had to do almost the same thing and I got it through listening events. If you just upload one file, you should listen to "sending" event, but if you want to enable multiple uploads you should listen to "sendingmultiple". Here is a piece of my code that I used to make this work:
Dropzone.options.myAwesomeForm = {
acceptedFiles: "image/*",
autoProcessQueue: false,
uploadMultiple: true,
parallelUploads: 100,
maxFiles: 100,
init: function() {
var myDropzone = this;
[..some code..]
this.on("sendingmultiple", function(files, xhr, formData) {
var attaches = $("input[type=file]").filter(function (){
return this.files.length > 0;
});
var numAttaches = attaches.length;
if( numAttaches > 0 ) {
for(var i = 0; i < numAttaches; i++){
formData.append(attaches[i].name, attaches[i].files[0]);
$(attaches[i]).remove();
}
}
});
[..some more code..]
}
}
And that's it. I hope you find it helpful :)
PS: Sorry if there's any grammar mistakes but English is not my native language

For future visitors
I've added this to dropzone options:
addedfile: function (file) {
var _this = this,
attachmentsInputContainer = $('#attachment_images');
file.previewElement = Dropzone.createElement(this.options.previewTemplate);
file.previewTemplate = file.previewElement;
this.previewsContainer.appendChild(file.previewElement);
file.previewElement.querySelector("[data-dz-name]").textContent = file.name;
file.previewElement.querySelector("[data-dz-size]").innerHTML = this.filesize(file.size);
if (this.options.addRemoveLinks) {
file._removeLink = Dropzone.createElement("<a class=\"dz-remove\" href=\"javascript:undefined;\">" + this.options.dictRemoveFile + "</a>");
file._removeLink.addEventListener("click", function (e) {
e.preventDefault();
e.stopPropagation();
if (file.status === Dropzone.UPLOADING) {
return Dropzone.confirm(_this.options.dictCancelUploadConfirmation, function () {
return _this.removeFile(file);
});
} else {
if (_this.options.dictRemoveFileConfirmation) {
return Dropzone.confirm(_this.options.dictRemoveFileConfirmation, function () {
return _this.removeFile(file);
});
} else {
return _this.removeFile(file);
}
}
});
file.previewElement.appendChild(file._removeLink);
}
attachmentsInputContainer.find('input').remove();
attachmentsInputContainer.append(Dropzone.instances[0].hiddenFileInput).find('input').attr('name', 'files');
return this._updateMaxFilesReachedClass();
},
This is default implementation of dropzone's addedfile option with 3 insertions.
Declared variable attachmentsInputContainer. This is invisible block. Something like
<div id="attachment_images" style="display:none;"></div>
Here I store future input with selected images
Then in the end of function remove previously added input(if any) from block and add new
attachmentsInputContainer.find('input').remove();
attachmentsInputContainer.append(Dropzone.instances[0].hiddenFileInput).find('input').attr('name', 'files');
And now, when you send form via simple submit button, input[name="files"] with values will be send.
I've made this hack because I append files to post that maybe not created yet

This is what I used for my past projects,
function makeDroppable(element, callback) {
var input = document.createElement('input');
input.setAttribute('type', 'file');
input.setAttribute('multiple', true);
input.style.display = 'none';
input.addEventListener('change', triggerCallback);
element.appendChild(input);
element.addEventListener('dragover', function(e) {
e.preventDefault();
e.stopPropagation();
element.classList.add('dragover');
});
element.addEventListener('dragleave', function(e) {
e.preventDefault();
e.stopPropagation();
element.classList.remove('dragover');
});
element.addEventListener('drop', function(e) {
e.preventDefault();
e.stopPropagation();
element.classList.remove('dragover');
triggerCallback(e);
});
element.addEventListener('click', function() {
input.value = null;
input.click();
});
function triggerCallback(e) {
var files;
if(e.dataTransfer) {
files = e.dataTransfer.files;
} else if(e.target) {
files = e.target.files;
}
callback.call(null, files);
}
}

Related

jQuery Drag-and-Drop + click Image Upload

I would like to have a simple drop zone to upload image via AJAX and jQuery. I have found some plugins but they are way too customized for what's needed, and I cannot get any of them working properly.
I also would like the drop zone to be clickable, in order to manually choose a file from the OS file dialog.
I found this script, that works fine but where the drop zone is not clickable:
// ---------------------------- drop zone to upload image : '#dropfile'
$(document).on('dragenter', '#dropfile', function() {
return false;
});
$(document).on('dragover', '#dropfile', function(e){
e.preventDefault();
e.stopPropagation();
return false;
});
$(document).on('dragleave', '#dropfile', function(e) {
e.preventDefault();
e.stopPropagation();
return false;
});
$(document).on('drop', '#dropfile', function(e) {
if(e.originalEvent.dataTransfer){
if(e.originalEvent.dataTransfer.files.length) {
// Stop the propagation of the event
e.preventDefault();
e.stopPropagation();
// Main function to upload
upload(e.originalEvent.dataTransfer.files);
}
}
return false;
});
function upload(files) {
var f = files[0] ;
// Only process image files.
if (!f.type.match('image/jpeg')) {
alert(‘The file must be a jpeg image’) ;
return false ;
}
var reader = new FileReader();
// When the image is loaded, run handleReaderLoad function
reader.onload = handleReaderLoad;
// Read in the image file as a data URL.
reader.readAsDataURL(f);
}
function handleReaderLoad(evt) {
var pic = {};
pic.file = evt.target.result.split(',')[1];
var str = jQuery.param(pic);
$.ajax({
type: 'POST',
url: ‘url_to_php_script.php’,
data: str,
success: function(data) {
//do_something(data) ;
}
});
}
So I added an invisible file type input, but image data seems to be sent twice. I suppose it's due a bad event propagation with the original drop zone:
// ---------------------------- clickable drop zone with invisible file input '#inputFile'
$('#dropfile).on('click', function() {
$('input#inputFile').trigger('click');
$('input#inputFile').change(function(e) {
upload($('input#inputFile')[0].files);
});
});
I tried to add these lines but data is always sent twice:
$('#dropfile).on('click', function() {
$('input#inputFile').trigger('click');
$('input#inputFile').change(function(e) {
upload($('input#inputFile')[0].files);
// -------------- stop sending data twice ???
e.preventDefault();
e.stopPropagation();
return false;
});
});
I still don't know why data is sent twice but I found a better script here:
https://makitweb.com/drag-and-drop-file-upload-with-jquery-and-ajax/

NWJS updating progress bar during long loop javascript

I'm having some troubles with javascript.
I'm trying to do a desktop app with NW.JS. I have a .xml file which I drag and drop in my app then it run a function to read the XML do some stuff and save a new file in .csv
It's work fine but now i would be able to update a progress bar during the function...
I tried setInterval and setTimeOut() but I'mhaving always the same result : nothing append until the function is finished.
here is my code
//Same as $(document).ready();
function ready(fn) {
if (document.readyState != 'loading'){
fn();
} else {
document.addEventListener('DOMContentLoaded', fn);
}
}
//When the page has loaded, run this code
ready(function(){
// prevent default behavior from changing page on dropped file
window.ondragover = function(e) { e.preventDefault(); return false };
// NOTE: ondrop events WILL NOT WORK if you do not "preventDefault" in the ondragover event!!
window.ondrop = function(e) { e.preventDefault(); return false };
var holder = document.getElementById('holder');
holder.ondragover = function () { this.className = 'hover'; return false; };
holder.ondragleave = function () { this.className = ''; return false; };
holder.ondrop = function (e) {
e.preventDefault();
var file = e.dataTransfer.files[0],
reader = new FileReader();
reader.onload = function (event) {
########I'm doing stuff here to convert file and i want to update the progressbar##########
};
reader.readAsText(file);
//reader.readAsDataURL(file);
return false;
};
});
Thanks for your help
best regards,
After trying the same code in NWJS and Electron, I found the problem to be that any long-running process in the 'main' Chromium process blocks rendering. The solution is to spawn a child process that communicates via Node's IPC. More details in this answer.

jQuery How to detect if file is being currently uploading (event is runing)

I written this code:
var fi = self.find('.file');
fi.on('change', function() {
if(fi.prop('files').length === 1) {
var file = fi.prop('files')[0],
name = file.name,
ext = name.split('.').pop().toLowerCase(),
size = (file.size / 1048576).toFixed(2),
type = file.type;
if($.inArray(ext, ['jpg', 'png', 'gif']) == -1) {
return false;
}
if($.inArray(type, ['image/jpeg', 'image/png', 'image/gif']) == -1) {
return false;
}
if(size > 1.2) {
return false;
}
ajax(createData(file));
return false;
}
return false;
});
I am allowing to upload only 1 file at the time ( from html side, js side and php side of view ), but with this script if user selects bigger size file, lets say 2+ MB and he is really fast clicker he can select another file and it creates second event and both files are being uploaded to the server which causes chaos and problems. Also i will be implementing drag and drop upload option so as a beginner javascript coder im asking the community if there is a way to:
Prevent from triggering script while file is being already uploaded ( i dont mean methods like hide input or diable it or take off event listener for a while, i mean method that detects if event is running and prevent executing script ). I tried things like default prevent or stop propagation but these dont work obviously.
Adding a button that will cancel on going script ( meaning stop file uploading and "clean it up" so user can safetly try again )
Thank you in advance for all your hints and guidance ;)
I worked on this recently for one of my side projects. Here's a code sample:
var fileReader = new FileReader();
var fileFilter = /^(?:image\/bmp|image\/cis\-cod|image\/gif|image\/ief|image\/jpeg|image\/jpeg|image\/jpeg|image\/pipeg|image\/png|image\/svg\+xml|image\/tiff|image\/x\-cmu\-raster|image\/x\-cmx|image\/x\-icon|image\/x\-portable\-anymap|image\/x\-portable\-bitmap|image\/x\-portable\-graymap|image\/x\-portable\-pixmap|image\/x\-rgb|image\/x\-xbitmap|image\/x\-xpixmap|image\/x\-xwindowdump)$/i;
var imageObject = { valid: false };
fileReader.onload = function (fileReaderEvent) {
imageObject.data = fileReaderEvent.target.result;
};
var loadImage = function() {
if (element[0].files.length === 0) {
return;
}
var file = element[0].files[0];
imageObject.filename = file.name;
if (!fileFilter.test(file.type)) {
imageObject.error = 'You must select a valid image!';
imageObject.valid = false;
return;
}else{
imageObject.error = '';
imageObject.valid = true;
}
fileReader.readAsDataURL(file);
};
element.on('change', loadImage);
}
This was from an AngularJS project so I've removed all the angular components but it should be pretty easy to add in the necessary JQuery code.

Reloading a file using html input

I have a textarea that can, quite obviously, be edited using keyboard entry. I also want to be able to load a file using an html input. I have done so, using the onchange event. (jsfiddle code linked below).
Suppose I load a file using the file loader - which works correctly in the example.
Then, I edit this file. Realising that the changes I have made are not desired, I want to reload this file. However, when using the html input, nothing changes since the selected file remains the same (the onchange event is not triggered). Is there a way to reload a file using an html input. (The only workaround I have found is to load a different file, then reload the original file ... which is not very elegant).
http://jsfiddle.net/aroberge/8PZyK/1/
var load_file = function() {
$("#fileInput").show();
var fileInput = document.getElementById('fileInput');
fileInput.addEventListener('change', function(e) {
var file = fileInput.files[0];
var reader = new FileReader();
reader.onload = function(e) {
$("#editor").text(reader.result);
$("#fileInput").hide();
};
reader.readAsText(file);
});
};
$("#load").on("click", function(evt) {
load_file();
});
You could clear out the fileInput value after you've read the file from it:
updated fiddle:
http://jsfiddle.net/8PZyK/8/
var load_file = function() {
$("#fileInput").show();
var fileInput = document.getElementById('fileInput');
fileInput.addEventListener('change', function(e) {
if (fileInput.files && fileInput.files.length > 0) {
var file = fileInput.files[0];
var reader = new FileReader();
fileInput.value = "";
reader.onload = function(e) {
$("#editor").val(reader.result);
$("#fileInput").hide();
}
};
reader.readAsText(file);
});
};
$("#load").on("click", function(evt) {
load_file();
});
After the file input has changed, and you grab out the data, simple reset the input field like so:
fileInput.value = ""; // Or with jQuery, $('input[file]').val('')
This will trigger another change (which you'll want to ignore), but will allow the user to select the same file again and still give you a change event.

Removing a file in modern browsers

Problem
I am currently using ( https://github.com/blueimp/jQuery-File-Upload/wiki ) this jQuery HTML5 Uploader.
The basic version, no ui.
The big problem is, that I looked everywhere (Mozilla Developer Network, SO, Google, etc.) and found no solution for removing a files already added via dragNdrop or manually via the file input dialogue.
Why do I want to achieve removing a file?
Because it seems that HTML5 has a kind of "bug".
If you drop / select a file (file input has set multiple) upload it, and then drop / select another file you magically have now the new file twice and it gets uploaded twice.
To prevent this magic file caching the use would have to refresh the page, which is not what someone wants to have for his modern AJAX web app.
What I have tried so far:
.reset()
.remove()
Reset Button
Setting .val() to ''
This seems to be a general HTML5 JS problem not jQuery specific.
Theory
Might it be, that $j('#post').click (I bind / re-bind a lot of times different callbacks), stacks the callbacks methods so that each time the updateFileupload function is called an additional callback is set.
The actual problem would now not rely anymore on the HTML5 upload, it would now rely on my could, miss-binding the .click action on my submit button (id=#post).
If we now call .unbind before each .click there shouldn't be any duplicated callback binding.
Code
Function containing the upload code:
function updateFileupload (type) {
var destination = "";
switch(type)
{
case upload_type.file:
destination = '/wall/uploadfile/id/<?=$this->id?>';
break;
case upload_type.image:
destination = '/wall/upload/id/<?=$this->id?>';
break;
}
$j('#fileupload').fileupload({
dataType: 'json',
url: destination,
singleFileUploads: false,
autoUpload: false,
dropZone: $k(".dropZone"),
done: function (e, data) {
console.log("--:--");
console.log(data.result);
upload_result = data.result;
console.log(upload_result);
console.log("--:--");
console.log(type);
if(type == upload_type.image)
{
var imageName = upload_result.real;
console.log(imageName);
$k.get('/wall/addpicture/id/<?=$this->id ?>/name'+imageName, function(data){
if(data > 0){
console.log("I made it through!");
if(!data.id)
{
$k('#imgUpload').html('');
//$k('#imgPreview').fadeOut();
$k('#newPost').val('');
$k.get("/wall/entry/id/"+data, function(html){
$k('#postList').prepend(html);
});
}
}
});
}
},
send: function(e, data){
var files = data.files;
var duplicates = Array(); // Iterate over all entries and check whether any entry matches the current and add it to duplicates for deletion
for(var i=0; i<data.files.length;i++)
{
for(var j=0;j<data.files.length-1;j++)
{
if(files[i].name == files[j].name && i != j)
{
duplicates.push(j);
}
}
}
if(duplicates.length > 0)
{
for(var i=0;i<duplicates.length;i++)
files.splice(i, 1);
}
console.log("Duplicates");
console.log(duplicates);
},
drop: function(e, data){
console.log("outside");
// $k.each(data.files, function(index, file){
// $k('#imageListDummy').after('<li class="file-small-info-box">'+file.name+'</li>');
// console.log(file);
//
// });
},
add: function(e, data){
upload_data = data;
console.log(data);
$k.each(data.files, function(index, file){
$k('#imageListDummy').after('<li class="file-small-info-box">'+file.name+'</li>');
console.log(file);
});
$j('#post').click(function(event){
upload_data.submit();
if(type == upload_type.image)
{
var file = upload_data.files[0];
console.log("I am here");
console.log(file);
var img = document.createElement("img");
img.src = window.URL.createObjectURL(file);
img.height = 64;
img.width = 64;
img.onload = function(e) {
window.URL.revokeObjectURL(this.src);
}
document.getElementById('imgPreview').appendChild(img);
$k('#imgPreview').show();
}
clickPostCallback(event);
});
$j('#showSubmit').show();
}
});
}
It could be more a browser security issue.
Current file uploads specs don't allow javascript (or anything as far as I know) to tamper with the value of the file field even if to remove it.
So I would imagine any good file uploader would create multiple file upload fields so you can remove the entire field rather than play with the value?
This is speculation though.
Updated answer to Updated Question:
Shouldn't click() only be bound once? you shouldn't need to rebind a click event to a single element '#post' (unless this element changes, in which case it should really be a class). You can place the click() event binding outside of the options for file upload, as long as it's contained in a $(function(){} so it's when the DOM's ready.
Aside from that I'm trying to read the code without any HTML and no experience in multiple file uploading. The best thing to do is try and re-create it on jsfiddle.net, that way others can go in and play around with the code without affecting you and your likely to find the problem while putting the code in there anyway :)

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