helm: add custom labels for loki ingress (#10009)

**What this PR does / why we need it**:

Custom labels for ingresses are usually addressed from values files, so
we need this feature.

**Which issue(s) this PR fixes**:

**Special notes for your reviewer**:

**Checklist**
- [x] Reviewed the
[`CONTRIBUTING.md`](https://github.com/grafana/loki/blob/main/CONTRIBUTING.md)
guide (**required**)
- [x] Documentation added
- [x] Tests updated
- [x] `CHANGELOG.md` updated
- [x] If the change is worth mentioning in the release notes, add
`add-to-release-notes` label
- [x] Changes that require user attention or interaction to upgrade are
documented in `docs/sources/upgrading/_index.md`
- [x] For Helm chart changes bump the Helm chart version in
`production/helm/loki/Chart.yaml` and update
`production/helm/loki/CHANGELOG.md` and
`production/helm/loki/README.md`. [Example
PR](d10549e)

production/helm/loki/CHANGELOG.md

@@ -13,6 +13,10 @@ Entries should include a reference to the pull request that introduced the chang
 
 [//]: # (<AUTOMATED_UPDATES_LOCATOR> : do not remove this line. This locator is used by the CI pipeline to automatically create a changelog entry for each new Loki release. Add other chart versions and respective changelog entries bellow this line.)
 
+## 5.9.2
+
+- [ENHANCEMENT] Add custom labels value for loki ingress
+
 ## 5.9.1
 
 - [BUGFIX] Fix loki helm chart helper function for loki.host to explicitly include gateway port

production/helm/loki/Chart.yaml

@@ -3,7 +3,7 @@ name: loki
 description: Helm chart for Grafana Loki in simple, scalable mode
 type: application
 appVersion: 2.8.3
-version: 5.9.1
+version: 5.9.2
 home: https://grafana.github.io/helm-charts
 sources:
   - https://github.com/grafana/loki

production/helm/loki/README.md

@@ -1,6 +1,6 @@
 # loki
 
-![Version: 5.9.1](https://img.shields.io/badge/Version-5.9.1-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square) ![AppVersion: 2.8.3](https://img.shields.io/badge/AppVersion-2.8.3-informational?style=flat-square)
+![Version: 5.9.2](https://img.shields.io/badge/Version-5.9.2-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square) ![AppVersion: 2.8.3](https://img.shields.io/badge/AppVersion-2.8.3-informational?style=flat-square)
 
 Helm chart for Grafana Loki in simple, scalable mode
 

production/helm/loki/templates/ingress.yaml

@@ -7,6 +7,9 @@ metadata:
   namespace: {{ $.Release.Namespace }}
   labels:
     {{- include "loki.labels" . | nindent 4 }}
+    {{- with .Values.ingress.labels }}
+    {{- toYaml . | nindent 4 }}
+    {{- end }}
   {{- with .Values.ingress.annotations }}
   annotations:
     {{- toYaml . | nindent 4 }}

production/helm/loki/values.yaml

@@ -1130,6 +1130,8 @@ ingress:
   #    nginx.ingress.kubernetes.io/auth-secret-type: auth-map
   #    nginx.ingress.kubernetes.io/configuration-snippet: |
   #      proxy_set_header X-Scope-OrgID $remote_user;
+  labels: {}
+  #    blackbox.monitoring.exclude: "true"
   paths:
     write:
       - /api/prom/push