Add metrics service config to sciencemesh example (#4191)

* add metrics svc config to sciencemesh example

* Update sm-config-metrics.md changelog

* Fix sm-config-metrics.md PR link

changelog/unreleased/sm-config-metrics.md

@@ -0,0 +1,8 @@
+Enhancement: Add metrics service to ScienceMesh example config
+
+Adds the metrics http service configuration to the example config file
+of a ScienceMesh site. Having this service configured is a prerequisite
+for successfull Prometheus-based ScienceMesh sites metrics scraping.
+
+<https://github.com/cs3org/reva/pull/4186>
+<https://github.com/cs3org/reva/pull/4191>

examples/sciencemesh/metrics.json

@@ -0,0 +1,5 @@
+{
+    "cs3_org_sciencemesh_site_total_num_users": 0,
+    "cs3_org_sciencemesh_site_total_num_groups": 0,
+    "cs3_org_sciencemesh_site_total_amount_storage": 0
+}

examples/sciencemesh/sciencemesh.toml

@@ -278,6 +278,14 @@ prefix = "ocs"
 address = ":443"
 
 [http.services.prometheus]
+address = ":443"
+
+[http.services.metrics]
+address = ":443"
+metrics_data_driver_type = "json"
+metrics_data_location = "metrics.json"
+metrics_record_interval = 5000
+
 [http.services.sysinfo]
 
 [http.middlewares.cors]