Streaming Example From "Sinatra: Up and Running" Not Working - sinatra

Question

I am trying to run this example from the book Sinatra: Up and Running p. 46, but can't get it to work. Here's the program code:
require 'sinatra'
before do
content_type :txt
end
connections = []
get '/consume' do
stream(:keep_open) do |out|
# store connection for later on
connections << out
# remove connection when closed properly
out.callback { connections.delete(out) }
# remove connection when closed due to an error
out.errback do
logger.warn 'we just lost a connection!'
connections.delete(out)
end
end
end
get '/broadcast/:message' do
connections.each do |out|
out << "#{Time.now} -> #{params[:message]}" << "\n"
end
"Sent #{params[:message]} to all clients."
end
The instructions for testing the code are as follows:
It’s a little tricky to demonstrate the behavior in text, but a good demonstration would
be to start the application, then open a web browser and navigate to http://localhost:
4567/consume. Next, open a terminal and use cURL to send messages to the server.
$ curl http://localhost:4567/broadcast/hello
Sent hello to all clients.
If you look back at the web browser, you should see that the content of the page has
been updated with a time stamp and the message that you sent via the terminal. The
connection remains open, and the client continues to wait for further information from
the server.
When I follow these instruction, I get no errors, but the message "hello" does not appear in the browser. I am running Sinatra on with Webrick. Why is it not working?
Thanks!
UPDATE (Konstantin's Thin Suggestion)
I now start thin and perform the two steps described in the book and the OP. You can see that thin does indeed receive both requests. However, I am still not seeeing the output "hello" in the browser.
>rackup
>> Thin web server (v1.4.1 codename Chromeo)
>> Maximum connections set to 1024
>> Listening on 0.0.0.0:9292, CTRL+C to stop
127.0.0.1 - - [13/Aug/2012 12:48:03] "GET /consume HTTP/1.1" 200 - 0.0900
127.0.0.1 - - [13/Aug/2012 12:48:03] "GET /favicon.ico HTTP/1.1" 404 447 0.0000
127.0.0.1 - - [13/Aug/2012 12:49:02] "GET /broadcast/hello HTTP/1.1" 200 26 0.00
00
127.0.0.1 - - [13/Aug/2012 12:57:00] "GET /consume HTTP/1.1" 200 - 0.0000
Perhaps the mistake is in my configu.ru file:
require './streaming.rb'
run Sinatra::Application

Answer 1

Run Sinatra on Thin. :keep_open is not supported on Webrick. Make sure you're running Sinatra 1.3.3 or later.

Answer 2

I had the same problem. To speed up the response, I used
before do
content_type 'text/event-stream'
end

Answer 3

The second route has to be a POST:
post '/broadcast/:message' do
connections.each do |out|
out << "#{Time.now} -> #{params[:message]}" << "\n"
end
"Sent #{params[:message]} to all clients."
end
After that, you will also have to POST your message to the server:
curl -vX POST 127.0.0.1:4567/broadcast/hello