Disclaimer: This library is still work in progress.
SockJS is WebSocket emulation library. It means that you use the WebSocket API, only instead of WebSocket class you instantiate SockJS class. I highly recommend to read SockJS: WebSocket emulation on the RabbitMQ blog for more info.
Even though this library uses Rack interface, Thin is required as it supports asynchronous callback. For Websockets, we use faye-websocket gem.
For the client-side part you have to use JS library sockjs-client which provides WebSocket-like API. Here’s an example:
<script src="http://cdn.sockjs.org/sockjs-0.2.1.min.js"></script>
<script>
var sock = new SockJS("http://mydomain.com/my_prefix");
sock.onopen = function() {
console.log("open");
};
sock.onmessage = function(e) {
console.log("message", e.data);
};
sock.onclose = function() {
console.log("close");
};
</script>
Now in order to have someone to talk to, we need to run a server. That’s exactly what is sockjs-ruby good for:
#!/usr/bin/env ruby
# encoding: utf-8
require "rack"
require "rack/sockjs"
require "eventmachine"
# Your custom app.
class MyHelloWorld
def call(env)
body = "This is the app, not SockJS."
headers = {
"Content-Type" => "text/plain; charset=UTF-8",
"Content-Length" => body.bytesize.to_s
}
[200, headers, [body]]
end
end
app = Rack::Builder.new do
# Run one SockJS app on /echo.
use SockJS, "/echo" do |connection|
connection.subscribe do |session, message|
session.send(message)
end
end
# ... and the other one on /close.
use SockJS, "/close" do |connection|
connection.session_open do |session|
session.close(3000, "Go away!")
end
end
# This app will run on other URLs than /echo and /close,
# as these has already been assigned to SockJS.
run MyHelloWorld.new
end
EM.run do
thin = Rack::Handler.get("thin")
thin.run(app.to_app, Port: 8081)
end
For more complex example check examples/sockjs_apps_for_sockjs_protocol_tests.rb
- SockJS-client JavaScript client library.
- SockJS-node Node.js server.
- SockJS-ruby Ruby server.
- SockJS-protocol protocol tests and documentation.
- SockJS-protocol spec
Get sockjs-protocol (installation information are in its README) and run ./examples/sockjs_apps_for_sockjs_protocol_tests.rb. Now you can run the tests against it, for instance:
# Run all the tests. ./venv/bin/python sockjs-protocol-0.2.1.py # Run all the tests defined in XhrStreaming. ./venv/bin/python sockjs-protocol-0.2.1.py XhrStreaming # Run only XhrStreaming.test_transport test. ./venv/bin/python sockjs-protocol-0.2.1.py XhrStreaming.test_transport
