For a minimal Server

you only need to implement GET(), PUT() and PROPFIND(). Such a minimal server is not at all compliant to the sepcs but may already work with some clients.

For a DAV level 1 compliant server

you also need COPY(), MOVE(), DELETE() and PROPPATCH().

A DAV level 2 complient server

has to implement locking, so you also need LOCK(), UNLOCK() and CHECKLOCK().

A versioning server

as specified in RFC 3253 is beyond the current scope of the this PHP package.