rescue from connection reset by peer error and retry

Question

I am hitting an external service which does some password encryption and returns couple of things.

Now if I want to generate 50 passwords we run this function in a loop 50 times

def self.encrypt_password(password)
    retries = 2
    uri = URI
    params = Base64.encode64(password)
    uri.query = URI.encode("Source=#{params}")
    begin    
      retries.times.each do
        res = Net::HTTP.get_response(uri)
        if res.is_a?(Net::HTTPSuccess)
          obj = JSON.parse(res.body)
          pw = Base64.decode64(obj["Data"])
          ps = Base64.decode64(obj["Key"])

          pws = Iconv.iconv('ascii', 'utf-16', pws)
          return pwe,pws[0]
        end 
      end
    rescue
      raise "Error generating pws: #{$!}"
    end
  end

But the problem, i am encountering is that there are occasions when the service just returns the following error in the middle of a loop and exits:

"Connection reset by Peer error"

My question is how do I rescue from that error and retry a few times without breaking the flow of the program?

Or can someone recommend alternate solutions to my problem?

NOTE: I am using ruby on rails 2 and ruby 1.8.x

Answer 1

Ruby has the retry method, that can be used in the rescue clause.

It just runs the current method again, so you can use a counter to limit the number of retries:

def self.encrypt_password(password)
  retries = 2
  uri = URI
  params = Base64.encode64(password)
  uri.query = URI.encode("Source=#{params}")
  retries.times.each do
    res = Net::HTTP.get_response(uri)
    if res.is_a?(Net::HTTPSuccess)
      obj = JSON.parse(res.body)
      pw = Base64.decode64(obj["Data"])
      ps = Base64.decode64(obj["Key"])

      pws = Iconv.iconv('ascii', 'utf-16', pws)
      return pwe,pws[0]
    end 
  end
rescue SomeExceptionType
  if retries > 0
    retries -= 1
    retry
  else
    raise "Error generating pws: #{$!}"
  end
end

end