This caused me a bit of heartache and I found little to help via the usual channels.
I’d upgraded a Rails 2 app that used Delayed_Job to Rails 3 and was deploying the Heroku Cedar stack. Jobs were being queued but would fail immediately when trying to deserialise with
uninitialized constant Syck::Syck
when trying to parse and initialise the handler. Irritatingly the worker logs were showing the jobs as successful.
After messing around with trying to explicitly set the YAML parser in
config/boot.rb I found the solution.
Syck isn’t available on the Heroku Cedar stack so you have to include the
I then ran this on the console to resubmit the jobs and all was good
Delayed::Job.all.each do |job| job.invoke_job ; job.destroy end