rescue_each

Say you have a batch rake task which runs from cron which consists of many independent tasks ran in a loop. These tasks could be anything from updating cached database entries to file conversions.

Once of these tasks fails, perhaps there's a corrupt image. Normally this would mean the entire batch task fails. But with rescue_each the other items can be processed and any errors will be re-raised at the end to be caught by your cron script.

You can install from Gemcutter by running:

sudo gem install rescue_each

Simply replace your each calls with rescue_each:

BatchTasks.all.each &:process!

transforms into:

BatchTasks.all.rescue_each &:process!

rescue_each also supports a option to output error summary info to stderr during the loop:

(1..5).rescue_each :stderr => true do |i|
  sleep 1
  raise 'example'
end

You'll probably find this handy if your batch task has its own status output as this mode will output an error summary inline.

rescue_each also provides proxies for map, each_with_index, find_each and find_in_batches. You can also use rescue_each on any method taking a block by calling rescue_send:

odds = (1..5).rescue_send(:reject) { |i| i%2 == 0 }

• Fork the project.
• Make your feature addition or bug fix.
• Add tests for it. This is important so I don't break it in a future version unintentionally.
• Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
• Send me a pull request. Bonus points for topic branches.

Copyright (c) 2010 Jason Weathered. See LICENSE for details.