DRb - Distributed Ruby

a short introduction to Drb (without Rinda). Given at the Bangalore Ruby meetup on 18th May, 2013.

Transcript

1. DRb D i s t r i b u t e d R u b y 1 Monday, 20 May 13
2. What is DRb Distributed objects like Cobra and Java’s RMI No IDL or ceremony to use Magic happening under the covers 2 Monday, 20 May 13
3. Simple server require 'drb/drb' $SAFE = 1 # disable eval and friends SERVER_URI = "druby://127.0.0.1:8000" # simple class class TimeServer def get_current_time; Time.now; end end # bind to a port DRb.start_service(SERVER_URI, TimeServer.new) puts "listening on #{SERVER_URI}" DRb.thread.join 3 Monday, 20 May 13
4. Client require 'drb/drb' require 'pp' SERVER_URI = "druby://127.0.0.1:8000" timeserver = DRbObject.new_with_uri(SERVER_URI) pp timeserver #<DRb::DRbObject @uri= ..> puts timeserver.get_current_time 4 Monday, 20 May 13
5. What we saw service discovery is done through urls PORO - Server is a Plain old Ruby class A Stub is created Data is marshalled across It is a sync RPC call. not async by default 5 Monday, 20 May 13
6. What Next We were returning a standard ruby class. What about a custom class ? Let us try returning a object - what can go wrong ? 6 Monday, 20 May 13
7. Demo 7 Monday, 20 May 13
8. Skipped topics Rinda ACL for DRb Ruby safe levels DRb over SSL GC and DRb 8 Monday, 20 May 13
9. Usecase (not all of them are practical) For building RPC apis For building a distributed logging service. has the semantics of a method call A deployment bot. A daemon which is running on all nodes of a cluster listening for commands A background job worker map-reduce using Rinda. eg. starfish 9 Monday, 20 May 13