add option to expose metrics via nextcloud-exporter

.env.sample

@@ -107,3 +107,7 @@ DEFAULT_QUOTA="10 GB"
 #HSTS_ENABLED=1
 # Uncomment this line to add the `preload` part
 #HSTS_PRELOAD=1
+
+# Metrics
+# COMPOSE_FILE="$COMPOSE_FILE:compose.metrics.yml"
+# SECRET_METRICS_TOKEN_VERSION=v1 # length=32 charset=hex

README.md

@@ -128,6 +128,17 @@ To disable dashboard app (since it is so corporate):
 
 - Configure a `defaultapp` in your `config.php` or use [apporder](https://apps.nextcloud.com/apps/apporder)
 
+## Metrics
+
+There is a [metrics exporter](https://github.com/xperimental/nextcloud-exporter) that can be run as sidecar container, also part of the nextcloud helm charts. Its configured via alloys label-based auto-discovery provided by the updated [monitoring-stack](https://git.coopcloud.tech/coop-cloud/monitoring-ng)
+To enable, uncomment 
+```
+COMPOSE_FILE="$COMPOSE_FILE:compose.metrics.yml"
+SECRET_METRICS_TOKEN_VERSION=v1 # length=32 charset=hex
+```
+then generate the secret with abra and run
+`abra app cmd <domain> app set_metrics_token`
+
 ## Upgrading Nextcloud
 Upgrading Nextcloud can be a hair raising experiance. They [don't support downgrading](https://docs.nextcloud.com/server/latest/admin_manual/maintenance/upgrade.html) even for minor versions.
 

abra.sh

@@ -193,3 +193,7 @@ set_windowsfriendly_filenames() {
 upgrade_mariadb() {
     mariadb-upgrade -p`cat /run/secrets/db_root_password`
 }
+
+set_metrics_token() {
+    run_occ "config:app:set serverinfo token --value '$(cat /run/secrets/metrics_token)'"
+}

compose.metrics.yml

@@ -0,0 +1,22 @@
+version: "3.8"
+services:
+  app: 
+    secrets:
+      - metrics_token
+  metrics:
+    image: xperimental/nextcloud-exporter:0.9.0
+    environment:
+      - NEXTCLOUD_SERVER=https://$DOMAIN
+      - NEXTCLOUD_AUTH_TOKEN=@/run/secrets/metrics_token
+    secrets:
+      - metrics_token
+    networks:
+      - proxy
+    deploy:
+      labels:
+        - "prometheus.io/scrape=true"
+        - "prometheus.io/port=9205"
+secrets:
+  metrics_token:
+    external: true
+    name: ${STACK_NAME}_metrics_token_${SECRET_METRICS_TOKEN_VERSION}