How to upload base64 image resource with dropzone? - javascript

I'm trying to upload generated client side documents (images for the moment) with Dropzone.js.
// .../init.js
var myDropzone = new Dropzone("form.dropzone", {
autoProcessQueue: true
});
Once the client have finished his job, he just have to click a save button which call the save function :
// .../save.js
function save(myDocument) {
var file = {
name: 'Test',
src: myDocument,
};
console.log(myDocument);
myDropzone.addFile(file);
}
The console.log() correctly return me the content of my document
data:image/png;base64,iVBORw0KGgoAAAANS...
At this point, we can see the progress bar uploading the document in the drop zone but the upload failed.
Here is my (standart dropzone) HTML form :
<form action="/upload" enctype="multipart/form-data" method="post" class="dropzone">
<div class="dz-default dz-message"><span>Drop files here to upload</span></div>
<div class="fallback">
<input name="file" type="file" />
</div>
</form>
I got a Symfony2 controller who receive the post request.
// Get request
$request = $this->get('request');
// Get files
$files = $request->files;
// Upload
$do = $service->upload($files);
Uploading from the dropzone (by drag and drop or click) is working and the uploads are successfull but using the myDropzone.addFile() function return me an empty object in my controller :
var_dump($files);
return
object(Symfony\Component\HttpFoundation\FileBag)#11 (1) {
["parameters":protected]=>
array(0) {
}
}
I think i don't setup correctly my var file in the save function.
I tryied to create JS image (var img = new Image() ...) but without any success.
Thanks for your help !

Finally i found a working solution without creating canvas :
function dataURItoBlob(dataURI) {
'use strict'
var byteString,
mimestring
if(dataURI.split(',')[0].indexOf('base64') !== -1 ) {
byteString = atob(dataURI.split(',')[1])
} else {
byteString = decodeURI(dataURI.split(',')[1])
}
mimestring = dataURI.split(',')[0].split(':')[1].split(';')[0]
var content = new Array();
for (var i = 0; i < byteString.length; i++) {
content[i] = byteString.charCodeAt(i)
}
return new Blob([new Uint8Array(content)], {type: mimestring});
}
And the save function :
function save(dataURI) {
var blob = dataURItoBlob(dataURI);
myDropzone.addFile(blob);
}
The file appears correctly in dropzone and is successfully uploaded.
I still have to work on the filename (my document is named "blob").
The dataURItoBlob function have been found here : Convert Data URI to File then append to FormData
[EDIT] : I finally wrote the function in dropzone to do this job. You can check it here : https://github.com/CasperArGh/dropzone
And you can use it like this :
var dataURI = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAmAAAAKwCAYAAA...';
myDropzone.addBlob(dataURI, 'test.png');

I can't comment currently and wanted to send this to you.
I know you found your answer, but I had some trouble using your Git code and reshaped it a little for my needs, but I am about 100% positive this will work for EVERY possible need to add a file or a blob or anything and be able to apply a name to it.
Dropzone.prototype.addFileName = function(file, name) {
file.name = name;
file.upload = {
progress: 0,
total: file.size,
bytesSent: 0
};
this.files.push(file);
file.status = Dropzone.ADDED;
this.emit("addedfile", file);
this._enqueueThumbnail(file);
return this.accept(file, (function(_this) {
return function(error) {
if (error) {
file.accepted = false;
_this._errorProcessing([file], error);
} else {
file.accepted = true;
if (_this.options.autoQueue) {
_this.enqueueFile(file);
}
}
return _this._updateMaxFilesReachedClass();
};
})(this));
};
If this is added to dropzone.js (I did just below the line with Dropzone.prototype.addFile = function(file) { potentially line 1110.
Works like a charm and used just the same as any other. myDropzone.addFileName(file,name)!
Hopefully someone finds this useful and doesn't need to recreate it!

1) You say that: "Once the client have finished his job, he just have to click a save button which call the save function:"
This implies that you set autoProcessQueue: false and intercept the button click, to execute the saveFile() function.
$("#submitButton").click(function(e) {
// let the event not bubble up
e.preventDefault();
e.stopPropagation();
// process the uploads
myDropzone.processQueue();
});
2) check form action
Check that your form action="/upload" is routed correctly to your SF controller & action.
3) Example Code
You may find a full example over at the official Wiki
4) Ok, thanks to your comments, i understood the question better:
"How can i save my base64 image resource with dropzone?"
You need to embedd the image content as value
// base64 data
var dataURL = canvas.toDataURL();
// insert the data into the form
document.getElementById('image').value = canvas.toDataURL('image/png');
//or jQ: $('#img').val(canvas.toDataURL("image/png"));
// trigger submit of the form
document.forms["form1"].submit();
You might run into trouble doing this and might need to set the "origin-clean" flag to "true". see http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#security-with-canvas-elements
how to save html5 canvas to server

Related

Encoding a CSV file using javascript and passing the value to a 2nd Cloud Page not working as expected

What I am trying to do : I have a cloud page where the user can upload CSV file. When user clicks on the “upload” button the a function called getBase64() is called (please refer the below code). The getBase64() function will encode the uploaded file and post it to a second cloud page.The second cloud page then takes the posted data.
Note: I am trying to adapt this solution to my need (csv file) by referring to this article partially https://sfmarketing.cloud/2020/02/29/create-a-cloudpages-form-with-an-image-file-upload-option/
What’s the problem : When I try to click the the “upload” button the page is not taking me to the second CloudPage. Please could anyone let me know what I am doing wrong here ?
Here is the code:
CloudPage 1
<input id="file" type="file" accept=".csv">
<br>
<button id="button">Upload</button>
<script runat="client">
document.getElementById("button")
.addEventListener("click", function() {
var files = document.getElementById("file").files;
if (files.length > 0) {
getBase64(files[0]);
}
});
function getBase64(file) {
var reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = function() {
//prepare data to pass to processing page
var fileEncoded = reader.result;
var base64enc = fileEncoded.split(";base64,")[1];
var fullFileName = document.getElementById("file").files[0].name;
var fileName = fullFileName.split(".")[0];
var assetName = fullFileName.split(".")[1];
fetch("https://cloud.link.example.com/PAGE2", { //provide URL of the processing page
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify({
base64enc: base64enc,
fileName: fileName,
assetName: assetName
})
})
.then(function(res) {
window.alert("Success!");
})
.catch(function(err) {
window.alert("Error!");
});
};
reader.onerror = function(error) {
console.log('Error: ', error);
};
}
</script>
CloudPage 2
<script runat="server">
var jsonData = Platform.Request.GetPostData();
var obj = Platform.Function.ParseJSON(jsonData);
</script>
I do not see any errors in the code and when I click on the upload button I get a success message but it does not take me to the second page. Please can anyone guide me how to retrieve this posted data in second page as I am not able to get the encoded data in page 2?

Pass file path to javascript input android

I understand that providing a physical file path to javascript is not possible due to security reasons. However, when I look at Mozilla's pdf.js and mupdf android pdf viewer I see this is very much possible. There is a mechanism by which I can pass a file path to javascript. I explored into PDF.js but it seemed little difficult to make use of when I needed a simple solution.
I want to pass android internal storage file location onto the following code instead of using input id="files" type="file" which requires me to browse and select file. In my case I want to just pass file location from sdcard.
The following code actually loads ms word (docx) file as html which I then will show in webview in my project. In the case of pdf.js we were using it to display pdf in the similar way.
<script>
$(document).ready(function(){
//Input File
var $files = $('#files');
//File Change Event
$files.on('change', function (e) {
//File Object Information
var files = e.target.files;
//Create DocxJS
var docxJS = new DocxJS();
//File Parsing
docxJS.parse(
files[0],
function () {
//After Rendering
docxJS.render($('#loaded-layout')[0], function (result) {
if (result.isError) {
console.log(result.msg);
} else {
console.log("Success Render");
}
});
}, function (e) {
console.log("Error!", e);
}
);
});
});
</script>
<input id="files" type="file" name="files[]" multiple="false" />
<div id="loaded-layout" style="width:100%;height:800px;">
</div>
You can check code of PDF.JS based pdfviewer in android here.
What I found on the PDF.js code which was used to input file :
In pdffile.js included in index.html file, url variable was mentioned pointing to real location of the file i.e. in assets folder which then was used in pdf.js but at that point the usage seems confusing. Is there any way by which I can use real path of file or pass real path somehow in android for my purpose of viewing docx?
UPDATE :
I find that PDF.js by Mozilla actually treats file location as a url and so the file in the url is converted to javascript file object or blob. Hence I create a blob of the url from server using Ajax :
var myObject;
var xhr = new XMLHttpRequest();
xhr.open("GET","10143.docx",true); // adding true will make it work asynchronously
xhr.responseType = 'blob';
xhr.onload = function(e) {
if (this.status == 200){
//do some stuff
myObject = this.response;
}
};
xhr.send();
$(document).ready(function(){
//Input File
var $files = $('#files');
//File Change Event
$files.on('change', function (e) {
//File Object Information
var files = myObject.files;
//Create DocxJS
var docxJS = new DocxJS();
//File Parsing
docxJS.parse(
blobToFile(myObject, "10143.docx"),
function () {
//After Rendering
docxJS.render($('#loaded-layout')[0], function (result) {
if (result.isError) {
console.log(result.msg);
} else {
console.log("Success Render");
}
});
}, function (e) {
console.log("Error!", e);
}
);
});
});
function blobToFile(theBlob, fileName){
//A Blob() is almost a File() - it's just missing the two properties below which we will add
theBlob.lastModifiedDate = new Date();
theBlob.name = fileName;
return theBlob;
}
However now that I do that I get Parsing error from DocxJS like : {isError: true, msg: "Parse Error."}

Using CKEditor custom filebrowser and upload with ASP.Net MVC

I have a MVC app that Im trying to use CKEditor with. One example I was looking at is here but there are many others. So far so good, but one section im still curious about, is the js that sends the selected file name back to the file upload dialog textbox.
<script type="text/javascript">
$(document).ready(function () {
$(".returnImage").click("click", function (e) {
var urlImage = $(this).attr("data-url");
window.opener.updateValue("cke_72_textInput", urlImage);
window.close();
});
});
</script>
In particular, the cke_72_textInput element. My example wasnt working initially, until I opened chrome dev tools and found the actual id of the textinput, which was in my case cke_76_textInput. Why the id change I wonder? Seems a little "fragile" to refer to a specific id like this? The above js code just takes the selected image file and returns it into the textbox of the fileupload dialog.
Is there something exposed that references this textbox element indirectly without specifying it by id (via the config for example)?
On view:
$(document).ready(function () {
CKEDITOR.replace('Text-area-name', {
filebrowserImageUploadUrl: '/Controller-name/UploadImage'
});
CKEDITOR.editorConfig = function (config) {
// Define changes to default configuration here. For example:
config.language = 'de';
// config.extraPlugins = 'my_own_plugin'; // if you have any plugin
// config.uiColor = '#AADC6E';
// config.image_previewText = CKEDITOR.tools.repeat(' Hier steht dann dein guter Text. ', 8 );
// config.contentsLanguage = 'de';
config.height = 350; // 350px, specify if you want a larger height of the editor
config.linkShowAdvancedTab = false;
config.linkShowTargetTab = false;
};
CKEDITOR.on('dialogDefinition', function (ev) {
var dialogName = ev.data.name;
var dialogDefinition = ev.data.definition;
ev.data.definition.resizable = CKEDITOR.DIALOG_RESIZE_NONE;
if (dialogName == 'link') {
var infoTab = dialogDefinition.getContents('info');
infoTab.remove('protocol');
dialogDefinition.removeContents('target');
dialogDefinition.removeContents('advanced');
}
if (dialogName == 'image') {
dialogDefinition.removeContents('Link');
dialogDefinition.removeContents('advanced');
var infoTab = dialogDefinition.getContents('info');
infoTab.remove('txtBorder');
infoTab.remove('txtHSpace');
infoTab.remove('txtVSpace');
infoTab.remove('cmbAlign');
}
});
}
On Contoller:
[HttpPost]
public ActionResult UploadImage(HttpPostedFileBase file, string CKEditorFuncNum, string CKEditor, string langCode)
{
if (file.ContentLength <= 0)
return null;
// here logic to upload image
// and get file path of the image
const string uploadFolder = "Assets/img/";
var fileName = Path.GetFileName(file.FileName);
var path = Path.Combine(Server.MapPath(string.Format("~/{0}", uploadFolder)), fileName);
file.SaveAs(path);
var url = string.Format("{0}{1}/{2}/{3}", Request.Url.GetLeftPart(UriPartial.Authority),
Request.ApplicationPath == "/" ? string.Empty : Request.ApplicationPath,
uploadFolder, fileName);
// passing message success/failure
const string message = "Image was saved correctly";
// since it is an ajax request it requires this string
var output = string.Format(
"<html><body><script>window.parent.CKEDITOR.tools.callFunction({0}, \"{1}\", \"{2}\");</script></body></html>",
CKEditorFuncNum, url, message);
return Content(output);
}
I had the same problem...a little frustrating that I couldn't find any official documentation, considering this seems like a common use case.
Anyways, take a look at the quick tutorial here: http://r2d2.cc/2010/11/03/file-and-image-upload-with-asp-net-mvc2-with-ckeditor-wysiwyg-rich-text-editor/. In case the link ever breaks, here's what I did.
[HttpPost]
public ActionResult UploadImage(HttpPostedFileBase upload, string ckEditorFuncNum)
{
/*
add logic to upload and save image here
*/
var path = "~/Path/To/image.jpg"; // Logical relative path to uploaded image
var url = string.Format("{0}://{1}{2}",
Request.Url.Scheme,
Request.Url.Authority,
Url.Content(path)); // URL path to uploaded image
var message = "Saved!"; // Optional
var output = string.Format("<script>window.parent.CKEDITOR.tools.callFunction({0}, '{1}', '{2}');</script>",
CKEditorFuncNum,
url,
message);
return Content(output);
}

Where is the file data sent with jQueryFileUpload?

I'm working on file uploads and I wanted a plugin that could let users easily update their profile pictures, or avatars, with one click. Someone recommended jQueryFileUpload by blueimp. I have the view part of it setup (a link which, when clicked, opens a filechooser dialog), but I'm having problems receiving the file data. Fiddler shows the file data being posted to the url I want, but I can't seem to find where the data of the file I selected is being stored. Using
print_r($_POST);
shows only one parameter.
My javascript is the following:
$(".hoverAction").on('click', function(e) {
$(".fileInput:first").fileupload({
url: "/user/update",
singleFileUploads: true,
formData: {
type: "avatar"
},
add: function(e, data) {
var goUpload = true;
var uploadFile = data.files[0];
if (!(/\.(gif|jpg|jpeg|tiff|png)$/i).test(uploadFile.name)) {
common.notifyError('You must select an image file only');
goUpload = false;
}
if (uploadFile.size > 2000000) { // 2mb
common.notifyError('Please upload a smaller image, max size is 2 MB');
goUpload = false;
}
if (goUpload == true) {
data.submit();
}
}
});
$(".fileInput:first").click();
And my POST handler is the following:
function updateAction() {
$type = $_POST['type'];
switch($type) {
case "avatar":
print_r($_POST); // returns only the type param
break;
case "cover":
break;
default:
}
}
You should follow the documentation on https://github.com/blueimp/jQuery-File-Upload/wiki/Setup on how to build the back end. The plugin archives contain a basic PHP example which you can use as a starting point.

How to change a file name and download it when a button is clicked using JavaScript

I have one download button created in JavaScript that links to particular file.
var strDownloadButton = "<br/><INPUT type="button" value="Download" onclick="add()"/>"
window.location.href = "/images/image1.jpg";
I have to rename the file image1 to image2 before downloading, so I use:
<a href="/images/image1.jpg" download="image2" >Download</a>
The problem is that there are 2 download buttons created (HTML5 download attribute created 1 more).
Is there any way to use the same button created by JavaScript, and refer into download attribute?
I have no idea what are you doing Brad Christie,
<a id="download" href="Chrysanthemum.jpg" download="image2" >Download</a>
document.getElementById("download").setAttribute("download", "image3")
here, you have an element that you want to download, you get the element and change its download attribute.
I'm not 100% sure it'll work, but I've done something like this before to download a resource and rename it using javascript. It does, however, mean the resource has to be on the same domain as the page otherwise you will run into a cross-domain security issue. Also, please excuse the fact that I'm using jQuery, but if you need to go without I'll let you look up how to make a cross-browser AJAX call.
With that said:
<!-- your anchor decorated with data-saveas -->
Download
<!-- wiring it up using jQuery/AJAX/Blob -->
<script type="text/javascript">
// Helper to convert AJAX response in to a BLOB
function dataToBlob(data, mimeString){
// convert data to ArrayBuffer
var buffer = new Int8Array(new ArrayBuffer(data.length));
for (var i = 0; i < data.length; i++){
buffer[i] = data.charCodeAt(i) & 0xff;
}
// http://stackoverflow.com/a/15302872/298053
try {
return new Blob([buffer],{type:mimeString});
} catch (e1) {
try {
var BlobBuilder = window.MozBlobBuilder || window.WebKitBlobBuilder || window.BlobBuilder;
if (e.name == 'TypeError' && window.BlobBuilder){
bb = new BlobBuilder();
bb.append([buffer.buffer]);
return bb.getBlob(mimeString);
} else if (e.name == 'InvalidStateError'){
return new Blob([buffer.buffer],{type:mimeString});
}
} catch (e2) {
}
}
return null;
}
// iterate over all the items that are marked as saveas
$('a[data-saveas]').each(function(){
var $this = $(this);
// Get the actual path and the destined name
var target = $this.prop('href'),
saveas = $this.data('saveas');
// make an ajax call to retrieve the resource
$.ajax({
url: target,
type: 'GET',
mimeType: 'text/plain; charset=x-user-defined'
}).done(function(data, textStatus, jqXHR){
var mimeString = jqXHR.getResponseHeader('Content-Type'),
blob = dataToBlob(data, mimeString);
if (blob){
// now modfy the anchor to use the blob instead of the default href
var filename = saveas,
href = (window.webkitURL || window.URL).createObjectURL(blob);
$this.prop({
'download': saveas,
'href': href,
'draggable': true
}).data({
'downloadurl': [mimeString, filename, href].join(':')
});
}
});
});
</script>
Not tested, but should work. Basically, you can go fetch the resource using jQuery and store it in to a blob with an assigned name. If it's able to do so, the link now becomes a custom-named blob resource with the provided name. if it can't the default functionality is retained and the user needs to name it his/herself.

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