Though I am working on the drag and drop for long I have never looked into acheiving Drag and Drop using keyboard to support a11y.
https://dev.opera.com/articles/accessible-drag-and-drop/ This link also by Gez Lemon helped me to understand a11y in drag and drop. Drag and Drop ally has two aria attributes.
This attibute is set to true, false or undefined
- If this attribute is set to true then the drag and drop has started.
- If this attribute is set to false then the item can be dragged
- If this attribute is set to undefined then the item cannot be dragged
This is a list of items that are set on the drop targets. The values are copy, move, reference,execute, popup and none. These is set on the object that the item has to be dropped.