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@maccman
Created June 26, 2012 02:49
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Sinatra Server Side Event streaming.
# Usage: redis-cli publish message hello
require 'sinatra'
require 'redis'
conns = []
get '/' do
erb :index
end
get '/subscribe' do
content_type 'text/event-stream'
stream(:keep_open) do |out|
conns << out
out.callback { conns.delete(out) }
end
end
Thread.new do
redis = Redis.connect
redis.psubscribe('message', 'message.*') do |on|
on.pmessage do |match, channel, message|
channel = channel.sub('message.', '')
conns.each do |out|
out << "event: #{channel}\n\n"
out << "data: #{message}\n\n"
end
end
end
end
__END__
@@ index
<article id="log"></article>
<script>
var source = new EventSource('/subscribe');
source.addEventListener('message', function (event) {
log.innerText += '\n' + event.data;
}, false);
</script>
@niklas
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niklas commented Oct 5, 2014

Thank you for that inspiration, I almost used faye..

There is a typo (?) in line 27, there should be only one newline to keep both lines close together:

      conns.each do |out|
        out << "event: #{channel}\n"
        out << "data: #{message}\n\n"
      end

Else the pushed message won't have the right type bound, and source.addEventListener('different'..) won't react at all.

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