CourseModel.getById(cid, (err,course) => {
if (!!err || !course || !course.uid.equals(uid))
return cb({errmsg:"Not your course"},{});
CourseModel.getById(cid, (err,course) => {
if (!!err || !course || !course.uid.equals(uid))
return cb({errmsg:"Not your course"},{});