Class: ZmqJsonRpc::Server

Inherits:
Object
  • Object
show all
Defined in:
lib/simple_json_rpc/server.rb

Overview

This class implements the server:

USE

class Proxy
  def some_method(a,b)
    return [a,b,{"XXXX"=> 1}]
  end
end
server = ZmqJsonRpc::Server.new(Proxy.new())
server.server_loop

If you want a non blocking server do

 server = ZmqJsonRpc::Server.new(Proxy.new())
 thread = Thread.new {
   server.server_loop
 }
# later either do
thread.join # waiting for the server to finish -- which is never!
# or
thread.exit # or end the thread

Instance Method Summary collapse

Constructor Details

#initialize(proxy, connect = "tcp://*:49200", logger = nil) ⇒ Server

For errors the spec says: The error codes from and including -32768 to -32000 are reserved for pre-defined errors. Any code within this range, but not defined explicitly below is reserved for future use. The error codes are nearly the same as those suggested for XML-RPC at the following url: xmlrpc-epi.sourceforge.net/specs/rfc.fault_codes.php

For details on the zmq gem, please see github.com/chuckremes/ffi-rzmq (best to look in the code)


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# File 'lib/simple_json_rpc/server.rb', line 31

def initialize(proxy, connect="tcp://*:49200", logger=nil)
  @connect = connect
  @proxy = proxy
  @logger = logger
end

Instance Method Details

#handle_request(request) ⇒ Object 


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# File 'lib/simple_json_rpc/server.rb', line 37

def handle_request(request)
  begin
    @logger.debug "zmqjsonrpc server received request: #{request}" unless @logger.nil?
    req_id = nil
    rpc = JSON.parse(request)
    raise "Received unsupprted jsonrpc version (#{rpc['jsonrpc']})" if rpc["jsonrpc"].strip != "2.0"
    rid = rpc["id"]
    method = rpc["method"]
    params = rpc["params"]

    @logger.debug "zmqjsonrpc server calls proxy method: #{method}(#{params.collect {|p| p.inspect}.join(", ")})" unless @logger.nil?
    result = @proxy.send(method.to_sym, *params)
    response = {
      id: rid,
      jsonrpc: "2.0",
      result: result
    }
    @logger.debug "zmqjsonrpc server sends response: #{response.inspect})" unless @logger.nil?
    return response.to_json
  rescue => e
    # If there is more time to spare, we could implement the actual error codes here.
    @logger.warn "zmqjsonrpc server caugth error during request handling: #{e.message.strip})" unless @logger.nil?
    response = {
      id: rid,
      jsonrpc: "2.0",
      error: {
        code: 32603,
        message: e.message,
        data: e.backtrace.inspect
      }
    }
    @logger.debug "zmqjsonrpc server sends response: #{response.inspect})" unless @logger.nil?
    return response.to_json
  end
end

#server_loop ⇒ Object 


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# File 'lib/simple_json_rpc/server.rb', line 73

def server_loop
  @context = ZMQ::Context.new(1)
  @socket = @context.socket(ZMQ::REP)
  @socket.bind(@connect)
  @logger.info "zmqjsonrpc server listens to #{@connect}" unless @logger.nil?
  begin
    loop do
      request = ''
      rc = @socket.recv_string(request)
      response = handle_request(request)
      @socket.send_string(response)
    end
  ensure
    @logger.info "zmqjsonrpc server shuts down" unless @logger.nil?
    @socket.close
    # @context.terminate
  end
end