include http status codes in heroku router integration

[ryandotsmith]

Right now, we track connect, service, and bytes from the router logs. It might be cool to also provide some metrics around HTTP status codes.

cc: @hgmnz

[hgmnz]

I approve this initiative. :cake:

[a-warner]

and heroku error codes!

[aseemk]

We'd love to see this as well! In my mind, there are at least three ways you could approach this:

• at=info vs. at=error. This wouldn't be bad, and would already give us a lot of value, but it'd only catch errors from Heroku's perspective (e.g. H12 timeout), not errors from our app's perspective.
• status=2xx vs. 3xx vs. 4xx vs. 5xx. This would be the ideal for us.
• status=200 vs. 201 vs. …. This'd offer the most ability to slice and dice, but the number of metrics would overwhelm us and is probably overkill.

Thanks for the consideration!

Edit/update: having metrics on the specific Heroku error codes probably suffers from the same overkill-ness as specific status codes.

[aseemk]

I should also add that I'm assuming these metrics would be counters (type count rather than sample or measure). Hence there'd be a separate metric for each "value" you count (2xx vs. 3xx, or 200 vs. 201, etc.)