stats: Extract route names with forward-slash

[kb000]

Commit Message: Extract route names with forward-slash.
Additional Description: RDS protocol allows almost any route name, and stats are lightly sanitized before emitting to statsd and prometheus endpoints. This change slightly relaxes the capture group for RDS route names in stats, instead of opening the floodgates to everything, because YAGNI.
Risk Level: Low
Testing: Updated unit test
Docs Changes: None
Release Notes: N/A
Platform Specific Features: None
Fixes: #32976

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🐱

Caused by: #33734 was opened by kb000.

see: more, trace.

[jmarantz]

/wait for CI

[kb000]

/retest

[kb000]

/ptal @jmarantz

[jmarantz]

lgtm modulo the usual concern that this might be a breaking change for someone. But I couldn't think of how it would break anything, so I'm approving.

@ggreenway wdyt?

[jmarantz]

Oh...one thing: can you take a quick look at the docs for route stats and see if they need to be updated?

[ggreenway]

LGTM

[jmarantz]

@kb100 before I merge can you just check to see if we should update doc for this syntax change?

[kb000]

Oh...one thing: can you take a quick look at the docs for route stats and see if they need to be updated?

Oh it looks like the regex needs to be a little more relaxed. Docs say ":" is allowed (and replaced), and it's not.
https://www.envoyproxy.io/docs/envoy/latest/configuration/http/http_conn_man/rds#statistics

[kb000]

Oh...one thing: can you take a quick look at the docs for route stats and see if they need to be updated?

Oh it looks like the regex needs to be a little more relaxed. Docs say ":" is allowed (and replaced), and it's not. https://www.envoyproxy.io/docs/envoy/latest/configuration/http/http_conn_man/rds#statistics

Nevermind, I misread it. The ":" never makes it into the stat name. It's sanitized out by sanitizeStatsName well before the tag extraction code.

[kb000]

@jmarantz no doc updates needed 👍
No restrictions on the route name in RDS were documented before (anything goes, as far as I can tell), so there's nothing to change there.
The minimal documentation on route name in RDS stats don't mention allowing, disallowing, or special handling for anything but ":", so I'd prefer to leave it vague.