Reimplement scoring and create connection abstraction

Co-authored-by: Felix Auringer <felix.auringer@student.hpi.uni-potsdam.de>

lib/container_connection.rb

@@ -0,0 +1,58 @@
+require 'faye/websocket/client'
+
+class ContainerConnection
+  EVENTS = %i[start message exit stdout stderr].freeze
+
+  def initialize(url)
+    @socket = Faye::WebSocket::Client.new(url, [], ping: 0.1)
+
+    %i[open message error close].each do |event_type|
+      @socket.on event_type, &:"on_#{event_type}"
+    end
+
+    EVENTS.each { |event_type| instance_variable_set(:"@#{event_type}_callback", lambda {}) }
+  end
+
+  def on(event, &block)
+    return unless EVENTS.include? event
+
+    instance_variable_set(:"@#{event}_callback", block)
+  end
+
+  def send(data)
+    @socket.send(data)
+  end
+
+  private
+
+  def parse(event)
+    JSON.parse(event.data).deep_symbolize_keys
+  end
+
+  def on_message(event)
+    event = parse(event)
+    case event[:type]
+    when :exit_code
+      @exit_code = event[:data]
+    when :stderr
+      @stderr_callback.call event[:data]
+      @message_callback.call event[:data]
+    when :stdout
+      @stdout_callback.call event[:data]
+      @message_callback.call event[:data]
+    else
+      :error
+    end
+  end
+
+  def on_open(event)
+    @start_callback.call
+  end
+
+  def on_error(event)
+  end
+
+  def on_close(event)
+    @exit_callback.call @exit_code
+  end
+end