New configuration options: "use_middleware" and "use_subscribers"

[teamon]

Allow users to turn off rack middleware and AS subscribers (might reference #48 #47 )

[teamon]

I'm looking at tests right now

[teamon]

Ok, tests are fixed now

[josephruscio]

@teamon thanks for submitting this! I'm going to circle with @nextmat about this and we'll sort something out soon.

[teamon]

WARNING - This PR will break starting worker (@metrics.check_worker) under passenger and unicorn

[nextmat]

@teamon Thanks for the PR! Yeah, disabling the entire worker will break unicorn startup and soon it will break startup under all clients. The metric disabling will need to happen at a lower level. Thanks for the warning. I'm likely going to tweak this to fix, unless you want to take a stab at it?

[josephruscio]

@nextmat now that this is in librato-rack, how hard is it to get in here. We're going to be moving to GA (i.e. paid plans) on Heroku shortly, and it would be great to have this option in place for our users who just want their custom metrics at that point in time.

[nextmat]

@teamon So I'm in the process of porting librato-rails to use the new code in librato-rack for its internals, but you can have the ability you were after now by just switching to using librato-rack now and setting the disable_rack_metrics config option to true.

This will mean including the librato-rack middleware manually and setting up your own Configuration instance so you can toggle the option. If you decide to do this just let me know if you have any questions. /cc @josephruscio

[nextmat]

@teamon Oh, also using the librato-rack path will work fine with unicorn as well.

[nextmat]

Going to go ahead and close this for now, will likely offer configurable suites support in the future.

For now librato-rack + the disable_rack_metrics config option is the way to go for this behavior.