Improve dashboard upload script (opea-project#625)

Single label is enough, and Grafana does not need to be restarted,
one just needs to wait enough for it to check+process new configMaps,
*and* reload of Grafana page.

Signed-off-by: Eero Tamminen <eero.t.tamminen@intel.com>

Author: eero-t

kubernetes-addons/Observability/README.md

@@ -122,16 +122,16 @@ You can either:
 
 - Import them manually to Grafana,
 - Use [`update-dashboards.sh`](./update-dashboards.sh) script to add them to Kubernetes as (more persistent) Grafana dashboard `configMap`s
-  - Script uses `$USER-<file name>` as dashboard `configMap` names, overwrites any pre-existing `configMap` with the same name, and _restarts Grafana_ so that it notices `configMap` updates
+  - Script uses `$USER-<file name>` as dashboard `configMap` names, and overwrites any pre-existing `configMap` with the same name
 - Or create your own dashboards based on them
 
 When dashboard is imported to Grafana, you can directly save changes to it, but such dashboards go away if Grafana is removed / re-installed. When dashboard is in `configMap`, Grafana saves its changes to a (selected) file, but you need to re-apply those files to Kubernetes with the script, for your changes to be there when that Grafana dashboard page is reloaded in browser.
 
 Gotchas for dashboard `configMap` script usage:
 
 - If you change dashboard file name, you need to change also its 'uid' field (at end of the file), otherwise Grafana will see multiple `configMap`s for the same dashboard ID
-  - If there's no `uid` specified for the dashboard, Grafana will generate one on `configMap` load. Meaning that dashboard ID, and Grafana URL to it, will change on every reload
-- Script assumes Prometheus / Grafana to be installed according to above instructions. If not, list of `labels` within script need to be updated to match Prometheus / Grafana installation
+- If there's no `uid` specified for the dashboard, Grafana will generate one on `configMap` load. Meaning that dashboard ID, and Grafana URL to it, will change on every reload
+- Script assumes default Prometheus / Grafana install (`monitoring` namespace, `grafana_dasboard=1` label identifying dashboard `configMap`s)
 
 NOTE: Services provide metrics only after they have processed at least one query, before that dashboards can be empty!
 

kubernetes-addons/Observability/update-dashboards.sh

@@ -15,14 +15,15 @@ selector="app.kubernetes.io/name=grafana"
 grafana="kubectl -n $ns get pod --selector $selector --field-selector=status.phase=Running -o name"
 
 # Labels needed in configMap to get (Helm installed) Grafana to load it as dashboard
-labels="grafana_dashboard=1 release=prometheus-stack app=kube-prometheus-stack-grafana"
+labels="grafana_dashboard=1"
 
 error_exit ()
 {
 	name=${0##*/}
 	echo
-	echo "Create/update dashboards specified in given JSON files to Grafana."
-	echo "Names for the created configMaps will be in '$USER-<filename>' format."
+	echo "Create/update dashboards specified in given JSON files for Grafana."
+	echo "Names for the created configMaps will be in '$USER-<filename>' format"
+	echo "and they go to (Grafana) '$ns' namespace."
 	echo
 	echo "usage: $name <JSON files>"
 	echo
@@ -44,11 +45,12 @@ for file in "$@"; do
 	if [ ! -f "$file" ]; then
 		error_exit "JSON file '$file' does not exist"
 	fi
-	# Dashboard 'uid' is optional, but it should have a title...
+	# Dashboard 'uid' is optional as Grafana can generate one...
 	uid=$(jq .uid "$file" | tail -1)
 	if [ -z "$uid" ]; then
 		error_exit "'$file' dashboard has invalid JSON"
 	fi
+	# ...but it should have a title.
 	title=$(jq .title "$file" | tail -1)
 	if [ "$title" = "null" ]; then
 		error_exit "'$file' dashboard has no 'title' field"
@@ -103,22 +105,4 @@ done
 
 rm $tmp
 
-echo
-echo "Restarting Grafana so that it notices updated dashboards..."
-pod=$($grafana)
-echo "kubectl -n $ns delete $pod"
-kubectl -n "$ns" delete "$pod"
-
-echo
-echo "Waiting until new Grafana instance is running..."
-while true; do
-	sleep 2
-	pod=$($grafana)
-	if [ -n "$pod" ]; then
-		break
-	fi
-done
-echo "kubectl -n $ns wait $pod --for=condition=Ready"
-kubectl -n "$ns" wait "$pod" --for=condition=Ready
-
-echo "DONE!"
+echo "DONE! => Dashboard(s) should appear in Grafana after 1 min wait *and* Grafana page reload."