fix: PodMonitor doesn't honor sonarWebContext and fails to monitor SonarQube

[wwsean08]

Hello,

Currently if you set the sonarWebContext and enable the PodMonitor via prometheusMonitoring.podMonitor.enabled, then it will fail to monitor, this is because while it is hard coded to poll /api/monitoring/metrics, SonarQube is listening at (as an example) /sonarqube/api/monitoring/metrics.

As a note, this change is based on how the readiness and liveness probes work, seen here for determining the URL.

Testing:

Validate SonarQube DCE with the podmonitor enabled but the sonar web context blank via the helm template command

---
# Source: sonarqube-dce/templates/prometheus-podmonitor.yaml
apiVersion: monitoring.coreos.com/v1
kind: PodMonitor
metadata:
  name: sonarqube-dce
  namespace: "default"
  labels:
    app: sonarqube-dce
spec:
  namespaceSelector:
    matchNames:
    - default
  selector:
    matchLabels:
      app: sonarqube-dce
  podMetricsEndpoints:
  - port: http
    path: /api/monitoring/metrics
    scheme: http
    interval: 30s
    bearerTokenSecret:
      name: sonarqube-dce-sonarqube-dce-monitoring-passcode
      key: SONAR_WEB_SYSTEMPASSCODE

Validate SonarQube DCE with the podmonitor enabled but the sonar web context /sonarqube via the helm template command

---
# Source: sonarqube-dce/templates/prometheus-podmonitor.yaml
apiVersion: monitoring.coreos.com/v1
kind: PodMonitor
metadata:
  name: sonarqube-dce
  namespace: "default"
  labels:
    app: sonarqube-dce
spec:
  namespaceSelector:
    matchNames:
    - default
  selector:
    matchLabels:
      app: sonarqube-dce
  podMetricsEndpoints:
  - port: http
    path: /sonarqube/api/monitoring/metrics
    scheme: http
    interval: 30s
    bearerTokenSecret:
      name: sonarqube-dce-sonarqube-dce-monitoring-passcode
      key: SONAR_WEB_SYSTEMPASSCODE

Validate SonarQube with the podmonitor enabled but the sonar web context blank via the helm template command

---
# Source: sonarqube/templates/prometheus-podmonitor.yaml
apiVersion: monitoring.coreos.com/v1
kind: PodMonitor
metadata:
  name: sonarqube
  namespace: "default"
  labels:
    app: sonarqube
spec:
  namespaceSelector:
    matchNames:
    - default
  selector:
    matchLabels:
      app: sonarqube
  podMetricsEndpoints:
  - port: http
    path: /api/monitoring/metrics
    scheme: http
    interval: 30s
    bearerTokenSecret:
      name: sonarqube-sonarqube-monitoring-passcode
      key: SONAR_WEB_SYSTEMPASSCODE

Validate SonarQube with the podmonitor enabled but the sonar web context /sonarqube via the helm template command

---
# Source: sonarqube/templates/prometheus-podmonitor.yaml
apiVersion: monitoring.coreos.com/v1
kind: PodMonitor
metadata:
  name: sonarqube
  namespace: "default"
  labels:
    app: sonarqube
spec:
  namespaceSelector:
    matchNames:
    - default
  selector:
    matchLabels:
      app: sonarqube
  podMetricsEndpoints:
  - port: http
    path: /sonarqube/api/monitoring/metrics
    scheme: http
    interval: 30s
    bearerTokenSecret:
      name: sonarqube-sonarqube-monitoring-passcode
      key: SONAR_WEB_SYSTEMPASSCODE

Please ensure your pull request adheres to the following guidelines:

• explain your motives to contribute this change: what problem you are trying to fix, what improvement you are trying to make
• Document your Changes in the CHANGELOG.md file of the respected chart as well as the Chart.yaml

[wwsean08]

Hey @davividal, just checking in on this, anything I can do to help you review this change?

[carminevassallo]

Dear @wwsean08,

Thanks for contributing to our helm chart!

Your suggestion is correct; we don't consider the sonarWebContext when setting the Prometheus-native endpoint in our PodMonitor. I just tested your proposed changes locally, and they work as expected. Kudos 👏

Given that we recently pushed some changes related to the monitoring part, could you please integrate those changes quickly and solve the small conflicts in the change descriptions?

[wwsean08]

Hey @carminevassallo, thanks for taking a look, I've rebased this based on main and have resolved the merge conflicts, hopefully it's good to go now.

[carminevassallo]

Thanks, it looks all good to me 🎊