zmqjsonrpc

This gem implements a very simple JSON RPC 2.0 client and server which uses zeroMQ for transport. Please install libzmq, e.g. via apt-get install libzmq3-dev.

Let's not talk too much, let's see some code:

  require 'rubygems'
  require 'zmqjsonrpc'
  
  # client request to a running server
  client = ZmqJsonRpc::Client.new("tcp://127.0.0.1:49200")
  client.some_method(1, "b", [1,{a:1}])

  # -or- a client with logger and error handling
  require 'logger'
  logger = Logger.new(STDOUT)
  client = ZmqJsonRpc::Client.new("tcp://127.0.0.1:49200", 10000, loggger)
  begin
    client.faulty_method()
  rescue ZmqJsonRpc::ClientError => e
    puts "bad things can happen..."
  end

  require 'rubygems'
  require 'zmqjsonrpc'

  class Proxy
    def some_method(a,b,c)
      # do you thing
      return ["xyz", 77]
    end
  end

  # blocking server
  proxy = Proxy.new()
  server = ZmqJsonRpc::Server.new(proxy, "tcp://*:49200")
  server.server_loop

  # -or- a server with your own logger
  require 'logger'
  logger = Logger.new(STDOUT)
  # ...
  server = ZmqJsonRpc::Server.new(proxy, "tcp://*:49200", logger)

  
  # -or- dispatch a thread
  server = ZmqJsonRpc::Server.new(proxy, "tcp://*:49200")
  thread = Thread.new {
    server.server_loop
  }
  # and cancel the thread if you want to shut the server down
  thread.exit

Resources

• API reference documentation
• The JSON RPC 2.0 Spec
• The used ZeroMQ gem and good examples
• Gem making

Stuff left to do

• Add support for by-name parameters (see the spec)
• Add individual exception classes in the client.
• Send different error codes if something goes wrong in the server.
• Keep the client connection alive instead of re-establishing every time.
• Add more tests.

License

This code is released under the terms of MIT License.

Contribute

Please do so! Just send a message or send a pull request. Especially, adding webrick for transport would be nice.