Comment 4 for bug 1653562

controller logs on the ERROR, as per bug 1805990

2018-11-30 08:21:22 ERROR juju.apiserver charms.go:479 returning error from POST /model/<uuid>/charms?%3Amodeluuid=<uuid>&revision=0&schema=local&series=xenial: [{github.com/juju/juju/apiserver/charms.go:69: } {github.com/juju/juju/apiserver/charms.go:61: cannot upload charm} {github.com/juju/juju/apiserver/charms.go:104: } {github.com/juju/juju/apiserver/charms.go:256: } {github.com/juju/juju/state/charm.go:678: } {github.com/juju/juju/state/charm.go:169: already exists}]