Does there exist a method to compute the K-theory $$K(A \rtimes G)$$ for a discrete, countable groupoid $G$ and $G$-$C^*$-algebra $A$? In good cases, say $G$ is ameanable.
Say, via Baum--Connes and a Chern-character? But which Chern character?
(This question has partial overlapp with K-theory of topological groupoids)
