Use faraday to allow EM HTTP backends

[betamatt]

I've run into a case where I have an EventMachine app that doesn't want to block while delivering Airbrake notices. Normally, I fix this by queuing the notice. However, this app is very thin and doesn't require messaging for anything else. It would be really heavy to run queueing infrastructure just for the occasional exception notice.

The obvious solution is for Airbrake to use faraday so that the backend can be switched from net_http to em-synchrony. However, this introduces a dependency that you may be trying to avoid. Is that the case or would you accept a patch?

[betamatt]

Alternatively, Airbrake could be refactored a little to allow a custom Sender class. That way I could package a faraday implementation in a separate gem without introducing dependencies to base airbrake.

[betamatt]

Investigating further I found that Airbrake can already be configured with a custom sender that responds to #send_to_airbrake. Works for my needs.

[thibaudgg]

@betamatt can you give an example on how you have do that. It would be great! Thanks.
I would like to use Airbrake inside a simple cramp app.

[betamatt]

https://github.com/Viximo/airbrake-faraday_sender

[thibaudgg]

Thanks!