retry_upto.rb

retry_upto.rb

# Ruby's `retry` with steroids:
#
# - retry up to 5 times without waiting between them and retrying after any exception
#
#     retry_upto(5) do ... end
#
# - retry up to 5 times, waiting 2 seconds between retries and retrying after any exception
#
#     retry_upto(5, :wait => 2) do ... end
#
# - retry up to 5 times without waiting between retries, retrying only after a ZeroDivisionError
#
#     retry_upto(5, :rescue_only => ZeroDivisionError) do ... end
#
# - retry up to 5 times, waiting 2 seconds between retries, retrying only after a ZeroDivisionError
#
#     retry_upto(5, :wait => 2, :rescue_only => ZeroDivisionError) do ... end

def retry_upto(max_retries = 1, options = {})
  wait_secs = options[:wait] || 0
  exception_class = options[:rescue_only] || Exception
  begin
    return yield if ((max_retries -= 1) > 0)
  rescue exception_class => e
    sleep(wait_secs)
    retry
  end
  yield
end

It's taking a way better shape thanks to @ped and @glenngillen!!!

Added :patience feature as I've seen this use case several times too, thanks @jaimeiniesta!

Code compacted by @lleirborras, thanks man!

I usually like to implement Object#first_you_respond_to(*methods) in my apps

Using it my implementation of retry_upto would be:

def retry_upto(max_retries = 1, opts = {})
yield
rescue (opts[:rescue_only] || Exception)
raise if (max_retries -= 1) == 0
if opts[:wait]
meth = opts[:patience].first_you_respond_to(:*, :call)
opts[:wait] = opts[:patience].send(meth, opts[:wait]) if meth
sleep opts[:wait]
end
retry
end

Hope you like it!

Sounds nice, though I'd prefer to keep this without external dependencies. I've finally published it as a gem: http://github.com/raul/retry_upto