Using amqp uri env var in jruby implementation

sylvilagus/jruby/lib/sylvilagus/ch02/hello_world.rb

@@ -8,7 +8,7 @@ module Sylvilagus::Ch02::HelloWorld
   module ClassMethods
     def with_hello_world_conn(&block)
       factory = ConnectionFactory.new
-      factory.uri = 'amqp://guest:guest@localhost:5672'
+      factory.uri = ENV.fetch('SYLVILAGUS_AMQP_URI')
       conn = factory.new_connection
       channel = conn.create_channel
       channel.exchange_declare('hello-exchange', 'direct', true)