How to catch errors and send them to Bugsnag when using `rails runner`?

Question

We're running several cron tasks in our server, and we start them all using rails runner, like this:

rails runner 'MyTask.run'

where MyTask is a class in the project. The thing is, we use Bugsnag to handle errors in case anything fails. When we run a rake task, Bugsnag saves the errors and lists them in their website. But this does not happen when using rails runner. How can I configure rails to send errors to Bugsnag when this happens?

Answer 1

Rails runner is very difficult to configure or to customize. That is because all it really is, is a script with this main body:

if code_or_file.nil?
  $stderr.puts "Run '#{$0} -h' for help."
  exit 1
elsif File.exist?(code_or_file)
  $0 = code_or_file
  Kernel.load code_or_file
else
  eval(code_or_file, binding, __FILE__, __LINE__)
end

As you can see, it just does an eval of the code you sent, so there's no wrapper, no class you can extend, and basically nothing you can configure. It is better to create a rake task to perform things the same way as runner, but this time in an environment that will be controlled by Rake, therefore allowing you to configure everything you need:

desc 'Wraps a runner command with rake'
task :runner, [:command] => :environment do |t, args|
  eval(args[:command])
end

Then, you call it using

rake 'runner["MyTask.run"]'

This will run the tasks in a very similar way to using rails runner, but in the context of rake (which will include using Bugsnag).