Elementary RPC

Elementary RPC is a basic Protobuf HTTP RPC gem which aims to provide:

  • Easy RPC usage
  • Parallelism by default
  • An easily extended RPC request pipeline

Sample Usage

For the following Protobuf RPC service definition:

package echoserv;

message String {
  required string data  = 1;
  optional int64 status = 2;
}

service Simple {
  rpc Echo (String) returns (String);
  rpc Reverse (String) returns (String);
}

A corresponding Ruby client might look something like this:

require 'rubygems'
require 'elementary'

require 'echoserv/service.pb' # Include our protobuf object declarations


hosts = [{:host => 'localhost', :port => '9292', :prefix => '/rpcserv'}]


# Let's use the Statsd middleware to send RPC timing and count information to 
# Graphite (this presumes we have already used `Statsd.create_instance` elsewhere
# in our code)
Elementary.use(Elementary::Middleware::Statsd, :client => Statsd.instance)


# Create our Connection object that knows about our Protobuf service
# definition
def connection
  return @connection if @connection

  @connection = Elementary::Connection.new(Echoserv::Simple,
                                             :hosts => hosts)
end
# Create a Protobuf message to send over RPC
msg = Echoserv::String.new(:data => str)


echoed = c.rpc.echo(msg) # => Elementary::Future
reversed = c.rpc.reverse(msg) # => Elementary::Future

sleep 10 # Twiddle our thumbs doing other things

puts {
  :echoed => echoed.value, # resolve the future and get our value out
  :reversed => reversed.value,
}.to_json

Installation

Add this line to your application's Gemfile:

gem 'elementary-rpc'

And then execute:

$ bundle

Or install it yourself as:

$ gem install elementary-rpc

Usage

TODO: Write usage instructions here

Contributing

  1. Fork it ( https://github.com/[my-github-username]/elementary-rpc/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request

Testing

Install ha-proxy for your OS For Mac OSX, good reference source is http://nepalonrails.tumblr.com/post/9674428224/setup-haproxy-for-development-environment-on-mac Sample ha-proxy config

cat /etc/haproxy.conf global maxconn 4096 pidfile ~/tmp/haproxy-queue.pid log /tmp/haproxy/log local0 log /tmp/haproxy/log local1 notice

defaults log global mode http timeout connect 300000 timeout client 300000 timeout server 300000 maxconn 2000 option redispatch retries 3 option httpclose option httplog option forwardfor option httpchk HEAD / HTTP/1.0

frontend http-farm-1 bind :8080 default_backend app1latest

frontend http-farm-2 bind :8070 default_backend app2latest

backend app1latest balance roundrobin server localhost_8000 localhost:8000

backend app2latest balance roundrobin

listen haproxyapp_admin:9100 127.0.0.1:9100 mode http stats uri /

Start ha-proxy listener haproxy -f /etc/haproxy.conf

Start the server hosting the rpc as below: bundle exec rpc_server start ./spec/support/simpleservice.rb -p 8000 --http

Run the tests bundle exec rspec spec