Fix for additional labels for falco-exporter servicemonitor

[rcompos]

Describe the bug

When deploying falco-exporter Helm chart with servicemonitor.additionallabels in values.yaml, the chart fails unless the value is a string, in which case the label is not created.

How to reproduce it

Edit values.yaml and add some servicemonitor additionallabels as map value(s).

serviceMonitor:
  # Enable the deployment of a Service Monitor for the Prometheus Operator.
  enabled: true
  additionalLabels:
    release: prom

⇒ helm upgrade --install falco-exporter . -f values.yaml -n falco
Error: UPGRADE FAILED: YAML parse error on falco-exporter/templates/servicemonitor.yaml: error converting YAML to JSON: yaml: line 10: mapping values are not allowed in this context

Expected behaviour

The additionallables should be created in the servicemonitor. In this case "release: prom".

⇒ kctl -n falco get servicemonitors falco-exporter -o yaml
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
...
  labels:
  ...
    release: prom
  ...

Screenshots

N/A

Environment

• Falco version:
  Falco version: 0.24.0
  Driver version: 85c88952b018fdbce2464222c3303229f5bfcfad

• System info:

• Cloud provider or hardware configuration:
  GCP GKE Kubernetes v1.16.12

• OS:
  "machine": "x86_64",
  "nodename": "gke-yolo-infra-dev-default-node-pool-4754cdf8-1s69",
  "release": "4.19.112+",
  "sysname": "Linux",
  "version": "Pull falco chart from helm/charts #1 SMP Thu May 21 12:32:38 PDT 2020"

• Installation method:
  Helm chart

Additional context

Here is the fix:

File: falco-exporter/templates/servicemonitor.yaml
see lines 8-10 under metadata.labels.

{{ if .Values.serviceMonitor.enabled }}
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
  name: {{ include "falco-exporter.fullname" . }}
  labels:
    {{- include "falco-exporter.labels" . | nindent 4 }}
    {{- range $key, $value := .Values.serviceMonitor.additionalLabels }}
    {{ $key }}: {{ $value | quote }}
    {{- end }}
  namespace: {{ .Release.Namespace }}
spec:
  endpoints:
  - port: metrics
    {{- if .Values.serviceMonitor.interval }}
    interval: {{ .Values.serviceMonitor.interval }}
    {{- end }}
    {{- if .Values.serviceMonitor.scrapeTimeout }}
    scrapeTimeout: {{ .Values.serviceMonitor.scrapeTimeout }}
    {{- end }}
  selector:
    matchLabels:
      {{- include "falco-exporter.selectorLabels" . | nindent 6 }}
{{- end }}

[leogr]

Hi @rcompos

Good catch!

Could you open a PR to fix it?

[rcompos]

I tried to open a PR but I don't have the privileges. Thanks!