metrics: scope metrics to active config, add optional per-host metrics (#6531)v2.9.0-beta.1

* Add per host config

* Pass host label when option is enabled

* Test per host enabled

* metrics: scope metrics per loaded config

* doc and linter

Signed-off-by: Mohammed Al Sahaf <[email protected]>

* inject the custom registry into the admin handler

Co-Authored-By: Dave Henderson <[email protected]>

* remove `TODO` comment

* fixes

Signed-off-by: Mohammed Al Sahaf <[email protected]>

* refactor to delay metrics admin handler provision

Signed-off-by: Mohammed Al Sahaf <[email protected]>

---------

Signed-off-by: Mohammed Al Sahaf <[email protected]>
Co-authored-by: Hussam Almarzooq <[email protected]>
Co-authored-by: Dave Henderson <[email protected]>

1 files changed, 37 insertions, 0 deletions

diff --git a/caddytest/integration/caddyfile_adapt/metrics_perhost.caddyfiletest b/caddytest/integration/caddyfile_adapt/metrics_perhost.caddyfiletest
new file mode 100644
index 000000000..499215515
--- /dev/null
+++ b/caddytest/integration/caddyfile_adapt/metrics_perhost.caddyfiletest
@@ -0,0 +1,37 @@
+{
+	servers :80 {
+		metrics {
+			per_host
+		}
+	}
+}
+:80 {
+	respond "Hello"
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":80"
+					],
+					"routes": [
+						{
+							"handle": [
+								{
+									"body": "Hello",
+									"handler": "static_response"
+								}
+							]
+						}
+					],
+					"metrics": {
+						"per_host": true
+					}
+				}
+			}
+		}
+	}
+}