clarify timing expectations for firehose

[ktdreyer]

Would you please clarify how soon we should see an event here in the firehose compared to publishing it upstream?

For example, if I push a new tag to GitHub, how long would I have to wait until I see it in the libraries.io firehose? Is libraries.io listening an event stream that GitHub publishes somewhere? Or is libraries.io polling GitHub on some interval?

[ktdreyer]

I found the Watcher class at https://github.com/librariesio/dispatch/blob/master/dispatch.rb . There's EventMachine.add_periodic_timer(30), so I guess this is polling all those upstream feeds every 30 seconds.

[katzj]

The upstream feeds get polled with that frequency... github gets instead watched off of the github sse stream

[ktdreyer]

Thanks, I've added this to the README here: #281