OpenLayers polygon might only include 3 points

[ksnabb]

If the feature rest receives a polygon with only 3 points it will throw an GEOS error,

OpenLayers seems to accept polygons drawn as lines e.g. the use clicks twice on the map of which the second one is a double click. In this situation the app will send a polygon with three points to the server.

This needs to be fixed either on the client side or on the server side.