Add Caddy

[roidelapluie]

Caddy has native prom metrics now.

Signed-off-by: Julien Pivotto roidelapluie@inuits.eu

[roidelapluie]

PR: caddyserver/caddy#3709
It is already released.

[brian-brazil]

👍

Given the cardinality issues that have been seen with other proxy systems, it'd be wise to allow the user to configure which caddy_admin_http_requests_total labels they want.

[roidelapluie]

Given the cardinality issues that have been seen with other proxy systems, it'd be wise to allow the user to configure which caddy_admin_http_requests_total labels they want.

cc @hairyhenderson

[hairyhenderson]

Thanks for adding this, @roidelapluie!

@brian-brazil the caddy_admin_http_requests_total metric in particular is internal and the path label (I expect that's what you're referring to) has limited cardinality (i.e. it's not just using req.URL.Path).

But, I do agree in general, and I'm planning on adding some more configurability. The initial goal was to just get some basic instrumentation enabled.

[brian-brazil]

Ah indeed, it was the non-admin one I meant. Assembling metric names form different places makes it hard to figure out what they are from simple reading/grepping of the code.