- begin
- @object.save!
- rescue ActiveRecord::RecordNotUnique => rn
- raise unless params[:ensure_unique_name]
-
- # Dig into the error to determine if it is specifically calling out a
- # (owner_uuid, name) uniqueness violation. In this specific case, and
- # the client requested a unique name with ensure_unique_name==true,
- # update the name field and try to save again. Loop as necessary to
- # discover a unique name. It is necessary to handle name choosing at
- # this level (as opposed to the client) to ensure that record creation
- # never fails due to a race condition.
- raise unless rn.original_exception.is_a? PG::UniqueViolation
-
- # Unfortunately ActiveRecord doesn't abstract out any of the
- # necessary information to figure out if this the error is actually
- # the specific case where we want to apply the ensure_unique_name
- # behavior, so the following code is specialized to Postgres.
- err = rn.original_exception
- detail = err.result.error_field(PG::Result::PG_DIAG_MESSAGE_DETAIL)
- raise unless /^Key \(owner_uuid, name\)=\([a-z0-9]{5}-[a-z0-9]{5}-[a-z0-9]{15}, .*?\) already exists\./.match detail
-
- # OK, this exception really is just a unique name constraint
- # violation, and we've been asked to ensure_unique_name.
- counter += 1
- @object.uuid = nil
- @object.name = "#{name_stem} (#{counter})"
- redo
- end while false