RPC using Redis

client.rb

require 'redis'
require 'securerandom'
require 'msgpack'

class RedisRpcClient

  def initialize(redis_url, list_name)
    @client = Redis.connect(url: redis_url)
    @list_name = list_name.to_s
  end

  def method_missing(name, *args)
    request = {
      'jsonrpc' => '2.0',
      'method' => name,
      'params' => args,
      'id' => SecureRandom.uuid
    }

    @client.lpush(@list_name, request.to_msgpack)
    channel, response = @client.brpop(request['id'], timeout=30)

    MessagePack.unpack(response)['result']
  end

end

client = RedisRpcClient.new('redis://localhost:6379', :fib)
(1..30).each { |i| puts client.fib(i) }

server.py

import redis
import msgpack

class Fibonacci:

  def fib(self,n):
    if n == 0:
      return 0
    elif n == 1:
      return 1
    else:
      return self.fib(n-1) + self.fib(n-2)


class RedisRpcServer:

  def __init__(self, redis_url, list_name, klass):
    self.client = redis.from_url(redis_url)
    self.list_name = list_name
    self.klass = klass

  def start(self):
    print("Starting RPC server for " + self.list_name)
    while True:
      channel, request = self.client.brpop('fib')
      request = msgpack.unpackb(request, encoding='utf-8')

      print("Working on request: " + request['id'])

      result = getattr(self.klass, request['method'])(*request['params'])

      reply = {
        'jsonrpc': '2.0',
        'result': result,
        'id': request['id']
      }

      self.client.rpush(request['id'], msgpack.packb(reply, use_bin_type=True))
      self.client.expire(request['id'], 30)


RedisRpcServer('redis://localhost:6379', 'fib', Fibonacci()).start()

server.rb

require 'redis'
require 'msgpack'


class Fibonacci

  def fib(n)
    case n
    when 0 then 0
    when 1 then 1
    else
      fib(n - 1) + fib(n - 2)
    end
  end

end


class RedisRpcServer

  def initialize(redis_url, list_name, klass)
    @client = Redis.connect(url: redis_url)
    @list_name = list_name.to_s
    @klass = klass
  end

  def start
    puts "Starting RPC server for #{@list_name}"
    while true
      channel, request = @client.brpop(@list_name)
      request = MessagePack.unpack(request)

      puts "Working on request: #{request['id']}"

      args = request['params'].unshift(request['method'])
      result = @klass.send *args

      reply = {
        'jsonrpc' => '2.0',
        'result' => result,
        'id' => request['id']
      }

      @client.rpush(request['id'], MessagePack.pack(reply))
      @client.expire(request['id'], 30)
    end

  end

end

RedisRpcServer.new('redis://localhost:6379', :fib,  Fibonacci.new).start