This extension can add the ability to allow user-drawn areas to be buffered. It will modify the shape inline, so the original shape is not natively recoverable.
Users can see the buffered shapes in the client!
This requires the use of JSTS. The instructions below will install a tested version of JSTS using bower.
To install bower globally:
npm install -g bower
cd extensions/ClientBuffer
# this will install all the required components
bower install
<script type="text/javascript" src="extensions/ClientBuffer/bower_components/jsts/lib/javascript.util.js"></script>
<script type="text/javascript" src="extensions/ClientBuffer/bower_components/jsts/lib/jsts.js"></script>
<script type="text/javascript" src="extensions/ClientBuffer/ClientBuffer.js"></script>