How to restart a hung MasterFile in Matterhorn

restart_masterfile.rb

empty = ActiveFedora::SimpleDatastream.xml_template.to_xml

mf = MasterFile.find(pid)                 # Load the MasterFile.
if mf.workflow_id.present?
  begin
    Rubyhorn.client.stop(mf.workflow_id)  # Stop the existing workflow.
  rescue                                  # Keep going even if stopping the workflow fails.
  end                                     # This means there might be more cleanup later.
end
mf.mhMetadata.content = empty             # Remove all Matterhorn-related fields.
mf.set_workflow                           # Reset the proper workflow.
mf.save                                   # Save the MasterFile so delayed_job can find it.
mf.process                                # Re-submit the job to Matterhorn via delayed_job.