+ def cancel(cascade: false, need_transaction: true)
+ if need_transaction
+ ActiveRecord::Base.transaction do
+ cancel(cascade: cascade, need_transaction: false)
+ end
+ return
+ end
+
+ if self.state.in?([RunningOnServer, RunningOnClient])
+ self.state = Paused
+ self.save!
+ elsif self.state != Paused
+ raise InvalidStateTransitionError
+ end
+
+ return if !cascade
+
+ # cancel all child jobs
+ children = self.components.andand.collect{|_, c| c['job']}.compact.collect{|j| j['uuid']}.compact
+
+ return if children.empty?
+
+ Job.where(uuid: children, state: [Job::Queued, Job::Running]).each do |job|
+ job.cancel(cascade: cascade, need_transaction: false)
+ end
+ end
+