bwt-uploader | Vaadin

Polymer component that allows uploading of images and pdf files

[ This description is mirrored from at on 2019-05-10 ]


bwt-uploader is a file uploader with support for pdf files, jpeg, png and bmp images written in Polymer. It follows a plug and play model with a few configurations needed to enable certain features. It is partially inspired by the vaadin uploader and came out as a result of a component we built at Blue Water Tracks. Images are converted to base64 images which might increase the size of the file by a small percentage.


  • Simple Drag and Drop along with browse option
  • Ability to upload images and pdf files
  • Down sample and resize images (optional)
  • Ability to upload pdf files
  • Preview of pdf and image files (just the first page in case of pdf files)
  • Progress Bar
  • Configurable AJAX options as well as ability to insert extra fields into the upload object
  • Ability to skip downsampling of image
  • Configurable maximum file size
  • Customizable CSS and shape of preview area


To install bower install bwt-uploader

To run the code, head into the component's folder and run polymer serve

To run the tests polymer test

Demo And Documentation


A simple example of an Image upload

<bwt-uploader target="[yourUrl]" method="PUT" body="[[your Object]]" value="[[valueToBeDatabindedAsOutput]]"></bwt-uploader>

Feedback and Contributions

Both are welcome, feel free to create an issue and we will try to come up with fixes or added features for requests.


@bhargavkonkathi Programming is like playing chess; each line is as important as each step to determine what kind of player or programmer you are. When ever not playing chess, it's Javascript, Java and mongodb.
@maisnamraju Javascript Ninja; saving the world with one line of javascript at a time. ;)
@dhrytsenko What is my opinion about JavaScript, NodeJS, MongoDB and Polymer? Building blocks to the future! Allowing me to help make the world a better place.


This project is licensed under the terms of the MIT license.


Link to this version
ImportedReleased 08 March 2018MIT License
Framework Support
Polymer 1.0+
Browser Independent
Install with
bower install --save bluewatertracks/bwt-uploader"#0.9.13"
Run the above Bower command in your project folder. If you have any issues installing, please contact the author.
Release notes - Version 0.9.13


  • polymer#Polymer/polymer#^1.4.0
  • iron-icon#^1.0.12
  • pdfjs-dist#^1.7.246
  • paper-progress#^1.0.11
  • paper-dialog#^1.1.0
  • iron-ajax#^1.4.3
  • paper-button#^1.0.14