Can I rescue Errno::ECONNREFUSED?

[Alex Young]

Hi there,

I'm trying to put a little robustness into a Rinda::Tuplespace setup,
and I've run into a slight snag.

Here's some example client code to show the problem:

require 'rinda/tuplespace'

class Producer
def initialize
DRb.start_service
@tuplespace =
Rinda::TupleSpaceProxy.new(DRbObject.new_with_uri('druby://localhost:8099'))

ping
end

def ping
counter = 0
while true
begin
@tuplespace.write([:test, counter += 1]) # <= problem line
rescue Errno::ECONNREFUSED => e
nil
end
sleep(1)
end
end
end

Producer.new

My problem is this: when I make the server glitch (by calling
DRb.stop_service() and DRb.start_service() with a slight delay between
them), I get an Errno::ECONNREFUSED thrown in the client at the problem
line marked above. The rescue doesn't catch it, though - the script
always terminates at that point with a stack dump. Is there a way to
catch it that I've missed? For completeness, here's the server code I'm
using for testing:

require 'rinda/tuplespace'

class Consumer < Rinda::TupleSpace
def puts
read_all([:test, nil]).each {|t| p t}
end
end

class ConsumerTester
def initialize
@tuplespace = Consumer.new
start_drb
Thread.new{while true do sleep(1); @tuplespace.puts; print '.';
STDOUT.flush end}
end

def start_drb
DRb.start_service('druby://localhost:8099', @tuplespace)
end

def glitch
DRb.stop_service
@tuplespace = Consumer.new
sleep(2)
start_drb
end

def join
DRb.thread.join
end
end

tester = ConsumerTester.new
sleep(5)
puts "Glitching..."
tester.glitch
tester.join

Thanks,

 

[Alex Young]

Hi there,

I'm trying to put a little robustness into a Rinda::Tuplespace setup,
and I've run into a slight snag.

<snip>

Never mind - it turns out I was trying to rescue the wrong exception
class. For reference, the Errno::ECONNREFUSED is actually wrapped in a
DRb:RbConnError exception, and rescuing that is enough.