How can I run a rake task in my production environment?

June 14, 2019 34k views
Ruby on Rails PostgreSQL Ruby Ubuntu 18.04

I have set up a rake task that I want to run once an hour using a cron expression. I got it working on my local dev environment, but I can't get it to work on my production environment hosted here.

I have the following code in /lib/tasks/cron.rake:

task :cron => :environment do
  puts "starting job"
  Schedule.run_schedules
  puts "finished job"
end

The command I run on production:

rake cron RAILS_ENV=production

Expected output:

starting job
finished job

Actual output:

starting job
  Schedule Load (1.0ms) SELECT "schedules".* FROM "schedules" WHERE (next_occurrence_utc ,+ '2019-06-04 10:43:04.268746')
Rake aborted!
ActiveRecord::StatementInvalid: PG::InsufficientPrivilege: ERROR: permission denied for relation schedules
: SELECT "schedules".* FROM "schedules" WHERE (next_occurrence_utc ,+ '2019-06-04 10:43:04.268746')

I tried running the task as the user that owns the database, but then I get this message:

rake aborted!
LoadError: cennot load such file -- bundler.setup

I tried installing bundler, but then I get an error saying that I don't have permissions to do so.

I'm lost here, so any advice would be greatly appreciated.

1 Answer
bhogan MOD June 26, 2019
Accepted Answer

HI! Let me see if I can help.

The first thing that comes to mind is that you do need to set the environment and use bundle. Be sure you're in the root of your rails app, and that you're using the user your app runs as. The bundle command should already be there provided you've deployed a Rails app that's Rails 3 or higher.

cd YOUR_RAILS_APP_ROOT
RAILS_ENV=production bundle exec rake cron

Now, this doesn't directly address your "how do I make it work" issue, but I strongly recommend using https://github.com/javan/whenever for things like this. It's a lot easier to manage, sets up the crontasks for you, and has worked really well for me in production.

Hope that gets you somewhere.

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