core/library/blueimp_upload/README.md

# jQuery File Upload Plugin

## Demo
[Demo File Upload](https://blueimp.github.io/jQuery-File-Upload/)

## Description
File Upload widget with multiple file selection, drag&drop support, progress bars, validation and preview images, audio and video for jQuery.  
Supports cross-domain, chunked and resumable file uploads and client-side image resizing. Works with any server-side platform (PHP, Python, Ruby on Rails, Java, Node.js, Go etc.) that supports standard HTML form file uploads.

## Setup
* [How to setup the plugin on your website](https://github.com/blueimp/jQuery-File-Upload/wiki/Setup)
* [How to use only the basic plugin (minimal setup guide).](https://github.com/blueimp/jQuery-File-Upload/wiki/Basic-plugin)

## Features
* **Multiple file upload:**  
  Allows to select multiple files at once and upload them simultaneously.
* **Drag & Drop support:**  
  Allows to upload files by dragging them from your desktop or filemanager and dropping them on your browser window.
* **Upload progress bar:**  
  Shows a progress bar indicating the upload progress for individual files and for all uploads combined.
* **Cancelable uploads:**  
  Individual file uploads can be canceled to stop the upload progress.
* **Resumable uploads:**  
  Aborted uploads can be resumed with browsers supporting the Blob API.
* **Chunked uploads:**  
  Large files can be uploaded in smaller chunks with browsers supporting the Blob API.
* **Client-side image resizing:**  
  Images can be automatically resized on client-side with browsers supporting the required JS APIs.
* **Preview images, audio and video:**  
  A preview of image, audio and video files can be displayed before uploading with browsers supporting the required APIs.
* **No browser plugins (e.g. Adobe Flash) required:**  
  The implementation is based on open standards like HTML5 and JavaScript and requires no additional browser plugins.
* **Graceful fallback for legacy browsers:**  
  Uploads files via XMLHttpRequests if supported and uses iframes as fallback for legacy browsers.
* **HTML file upload form fallback:**  
  Allows progressive enhancement by using a standard HTML file upload form as widget element.
* **Cross-site file uploads:**  
  Supports uploading files to a different domain with cross-site XMLHttpRequests or iframe redirects.
* **Multiple plugin instances:**  
  Allows to use multiple plugin instances on the same webpage.
* **Customizable and extensible:**  
  Provides an API to set individual options and define callBack methods for various upload events.
* **Multipart and file contents stream uploads:**  
  Files can be uploaded as standard "multipart/form-data" or file contents stream (HTTP PUT file upload).
* **Compatible with any server-side application platform:**  
  Works with any server-side platform (PHP, Python, Ruby on Rails, Java, Node.js, Go etc.) that supports standard HTML form file uploads.

## Requirements

### Mandatory requirements
* [jQuery](https://jquery.com/) v. 1.6+
* [jQuery UI widget factory](https://api.jqueryui.com/jQuery.widget/) v. 1.9+ (included): Required for the basic File Upload plugin, but very lightweight without any other dependencies from the jQuery UI suite.
* [jQuery Iframe Transport plugin](https://github.com/blueimp/jQuery-File-Upload/blob/master/js/jquery.iframe-transport.js) (included): Required for [browsers without XHR file upload support](https://github.com/blueimp/jQuery-File-Upload/wiki/Browser-support).

### Optional requirements
* [JavaScript Templates engine](https://github.com/blueimp/JavaScript-Templates) v. 2.5.4+: Used to render the selected and uploaded files for the Basic Plus UI and jQuery UI versions.
* [JavaScript Load Image library](https://github.com/blueimp/JavaScript-Load-Image) v. 1.13.0+: Required for the image previews and resizing functionality.
* [JavaScript Canvas to Blob polyfill](https://github.com/blueimp/JavaScript-Canvas-to-Blob) v. 2.1.1+:Required for the image previews and resizing functionality.
* [blueimp Gallery](https://github.com/blueimp/Gallery) v. 2.15.1+: Used to display the uploaded images in a lightbox.
* [Bootstrap](http://getbootstrap.com/) v. 3.2.0+
* [Glyphicons](http://glyphicons.com/)

The user interface of all versions except the jQuery UI version is built with [Bootstrap](http://getbootstrap.com/) and icons from [Glyphicons](http://glyphicons.com/).

### Cross-domain requirements
[Cross-domain File Uploads](https://github.com/blueimp/jQuery-File-Upload/wiki/Cross-domain-uploads) using the [Iframe Transport plugin](https://github.com/blueimp/jQuery-File-Upload/blob/master/js/jquery.iframe-transport.js) require a redirect back to the origin server to retrieve the upload results. The [example implementation](https://github.com/blueimp/jQuery-File-Upload/blob/master/js/main.js) makes use of [result.html](https://github.com/blueimp/jQuery-File-Upload/blob/master/cors/result.html) as a static redirect page for the origin server.

The repository also includes the [jQuery XDomainRequest Transport plugin](https://github.com/blueimp/jQuery-File-Upload/blob/master/js/cors/jquery.xdr-transport.js), which enables limited cross-domain AJAX requests in Microsoft Internet Explorer 8 and 9 (IE 10 supports cross-domain XHR requests).  
The XDomainRequest object allows GET and POST requests only and doesn't support file uploads. It is used on the [Demo](https://blueimp.github.io/jQuery-File-Upload/) to delete uploaded files from the cross-domain demo file upload service.

### Custom Backends

You can add support for various backends by adhering to the specification [outlined here](https://github.com/blueimp/jQuery-File-Upload/wiki/JSON-Response).

## Browsers

### Desktop browsers
The File Upload plugin is regularly tested with the latest browser versions and supports the following minimal versions:

* Google Chrome
* Apple Safari 4.0+
* Mozilla Firefox 3.0+
* Opera 11.0+
* Microsoft Internet Explorer 6.0+

### Mobile browsers
The File Upload plugin has been tested with and supports the following mobile browsers:

* Apple Safari on iOS 6.0+
* Google Chrome on iOS 6.0+
* Google Chrome on Android 4.0+
* Default Browser on Android 2.3+
* Opera Mobile 12.0+

### Supported features
For a detailed overview of the features supported by each browser version, please have a look at the [Extended browser support information](https://github.com/blueimp/jQuery-File-Upload/wiki/Browser-support).

## Contributing
**Bug fixes** and **new features** can be proposed using [pull requests](https://github.com/blueimp/jQuery-File-Upload/pulls).
Please read the [contribution guidelines](https://github.com/blueimp/jQuery-File-Upload/blob/master/CONTRIBUTING.md) before submitting a pull request.

## Support
This project is actively maintained, but there is no official support channel.  
If you have a question that another developer might help you with, please post to [Stack Overflow](http://stackoverflow.com/questions/tagged/blueimp+jquery+file-upload) and tag your question with `blueimp jquery file upload`.

## License
Released under the [MIT license](https://opensource.org/licenses/MIT).