feat: automatically roll deployments

The following patch extends the chart to automatically roll the deployment, when
one of the configurations, stored in a config map or secret, has been changed.

The implementation add annotations which triggers `helm update` or ArgoCD to
roll the deployment. Further information can be found on the official helm
website:

  https://helm.sh/docs/howto/charts_tips_and_tricks/#automatically-roll-deployments

Chart.yaml

@@ -2,7 +2,6 @@ apiVersion: v2
 name: prometheus-fail2ban-exporter
 description: Prometheus metric exporter for Fail2Ban
 type: application
-kubeVersion: ">=1.20.0"
 version: "0.1.0"
 appVersion: "0.1.1"
 

templates/prometheus-fail2ban-exporter/_pod.tpl

@@ -4,6 +4,21 @@
 
 {{- define "prometheus-fail2ban-exporter.pod.annotations" -}}
 {{ include "prometheus-fail2ban-exporter.annotations" . }}
+
+# The following annotations are required to trigger a rolling update. Further information can be found in the official
+# documentation of helm:
+#
+#   https://helm.sh/docs/howto/charts_tips_and_tricks/#automatically-roll-deployments
+#
+
+{{/* web config */}}
+{{- if and .Values.config.webConfig.existingSecret.enabled .Values.config.webConfig.existingSecret.secretName }}
+{{- $secret := default (dict "data" (dict)) (lookup "v1" "Secret" .Release.Namespace .Values.config.webConfig.existingSecret.secretName ) }}
+checksum/secret-web-config: {{ print $secret.spec | sha256sum }}
+{{- else }}
+checksum/secret-web-config: {{ include (print $.Template.BasePath "/prometheus-fail2ban-exporter/secretWebConfig.yaml") . | sha256sum }}
+{{- end }}
+
 {{- end }}
 
 {{/* labels */}}

templates/prometheus-fail2ban-exporter/daemonSet.yaml

@@ -17,6 +17,8 @@ spec:
       {{- include "prometheus-fail2ban-exporter.pod.selectorLabels" . | nindent 6 }}
   template:
     metadata:
+      annotations:
+        {{- include "prometheus-fail2ban-exporter.pod.annotations" . | nindent 8 }}
       labels:
         {{- include "prometheus-fail2ban-exporter.pod.labels" . | nindent 8 }}
     spec:

unittests/daemonset/daemonset.yaml

@@ -7,18 +7,22 @@ release:
   namespace: testing
 templates:
 - templates/prometheus-fail2ban-exporter/daemonSet.yaml
+- templates/prometheus-fail2ban-exporter/secretWebConfig.yaml
 tests:
 - it: Rendering default
   asserts:
   - hasDocuments:
       count: 1
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - containsDocument:
       apiVersion: apps/v1
       kind: DaemonSet
       name: prometheus-fail2ban-exporter-unittest
       namespace: testing
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: metadata.annotations
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: metadata.labels
       value:
@@ -27,15 +31,31 @@ tests:
         app.kubernetes.io/name: prometheus-fail2ban-exporter
         app.kubernetes.io/version: 0.1.0
         helm.sh/chart: prometheus-fail2ban-exporter-0.1.0
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
+  - exists:
+      path: spec.template.metadata.annotations.checksum/secret-web-config
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
+  - equal:
+      path: spec.template.metadata.labels
+      value:
+        app.kubernetes.io/instance: prometheus-fail2ban-exporter-unittest
+        app.kubernetes.io/managed-by: Helm
+        app.kubernetes.io/name: prometheus-fail2ban-exporter
+        app.kubernetes.io/version: 0.1.0
+        helm.sh/chart: prometheus-fail2ban-exporter-0.1.0
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.affinity
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.containers[0].envFrom
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.containers[0].args
       value:
       # - --web.config.file=/etc/prometheus-fail2ban-exporter/config.d/webConfig.yaml
       - --web.listen-address=:9191
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.containers[0].volumeMounts
       value:
@@ -43,6 +63,7 @@ tests:
         name: socket
       - mountPath: /etc/prometheus-fail2ban-exporter/config.d
         name: config-d
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.volumes
       value:
@@ -53,42 +74,59 @@ tests:
       - name: config-d
         secret:
           secretName: prometheus-fail2ban-exporter-unittest-web-config
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.containers[0].image
       value: git.cryptic.systems/volker.raschek/prometheus-fail2ban-exporter:0.1.0
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.containers[0].imagePullPolicy
       value: IfNotPresent
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.containers[0].resources
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.containers[0].securityContext
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.dnsConfig
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.dnsPolicy
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.hostname
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.hostNetwork
       value: false
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.imagePullSecrets
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.nodeSelector
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.priorityClassName
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.restartPolicy
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.subdomain
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.terminationGracePeriodSeconds
       value: 60
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.tolerations
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - notExists:
       path: spec.template.spec.topologySpreadConstraints
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.updateStrategy
       value:
@@ -96,6 +134,7 @@ tests:
           maxSurge: 1
           maxUnavailable: 0
         type: "RollingUpdate"
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test custom affinity
   set:
@@ -122,6 +161,7 @@ tests:
                 values:
                 - antarctica-east1
                 - antarctica-west1
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test additional arguments
   set:
@@ -136,6 +176,7 @@ tests:
       - --web.listen-address=:9191
       - --foo=bar
       - --bar=foo
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test custom imageRegistry and imageRepository
   set:
@@ -145,6 +186,7 @@ tests:
   - equal:
       path: spec.template.spec.containers[0].image
       value: registry.example.local/path/special/prometheus-fail2ban-exporter:0.1.0
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test custom imagePullPolicy
   set:
@@ -153,6 +195,7 @@ tests:
   - equal:
       path: spec.template.spec.containers[0].imagePullPolicy
       value: Always
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test config.webConfig.existingSecret
   set:
@@ -166,6 +209,7 @@ tests:
         name: socket
       - mountPath: /etc/prometheus-fail2ban-exporter/config.d
         name: config-d
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.volumes
       value:
@@ -176,6 +220,7 @@ tests:
       - name: config-d
         secret:
           secretName: web-config-secret
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test custom resource limits and requests
   set:
@@ -195,6 +240,7 @@ tests:
           resourceFieldRef:
             divisor: "1"
             resource: limits.cpu
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.containers[0].resources
       value:
@@ -204,6 +250,7 @@ tests:
         requests:
           cpu: 25m
           memory: 100MB
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test custom securityContext
   set:
@@ -230,6 +277,7 @@ tests:
         readOnlyRootFilesystem: true
         runAsNonRoot: true
         runAsUser: 1000
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test dnsConfig
   set:
@@ -244,6 +292,7 @@ tests:
         nameservers:
         - "8.8.8.8"
         - "8.8.4.4"
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test dnsPolicy
   set:
@@ -252,6 +301,7 @@ tests:
   - equal:
       path: spec.template.spec.dnsPolicy
       value: ClusterFirst
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test hostNetwork, hostname, subdomain
   set:
@@ -262,12 +312,15 @@ tests:
   - equal:
       path: spec.template.spec.hostNetwork
       value: true
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.hostname
       value: pg-exporter
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.subdomain
       value: exporters.internal
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test imagePullSecrets
   set:
@@ -280,6 +333,7 @@ tests:
       value:
       - name: my-pull-secret
       - name: my-special-secret
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test nodeSelector
   set:
@@ -290,6 +344,7 @@ tests:
       path: spec.template.spec.nodeSelector
       value:
         foo: bar
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test priorityClassName
   set:
@@ -298,6 +353,7 @@ tests:
   - equal:
       path: spec.template.spec.priorityClassName
       value: my-priority
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test restartPolicy
   set:
@@ -306,6 +362,7 @@ tests:
   - equal:
       path: spec.template.spec.restartPolicy
       value: Always
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test terminationGracePeriodSeconds
   set:
@@ -314,6 +371,7 @@ tests:
   - equal:
       path: spec.template.spec.terminationGracePeriodSeconds
       value: 120
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test tolerations
   set:
@@ -330,6 +388,7 @@ tests:
         operator: Equal
         value: fail2ban
         effect: NoSchedule
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test topologySpreadConstraints
   set:
@@ -348,6 +407,7 @@ tests:
         labelSelector:
           matchLabels:
             app.kubernetes.io/instance: prometheus-fail2ban-exporter
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
 
 - it: Test additional volumeMounts and volumes
   set:
@@ -366,6 +426,7 @@ tests:
         mountPath: /usr/lib/prometheus-fail2ban-exporter/data
       - name: config-d
         mountPath: /etc/prometheus-fail2ban-exporter/config.d
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml
   - equal:
       path: spec.template.spec.volumes
       value:
@@ -374,4 +435,5 @@ tests:
           path: /usr/lib/prometheus-fail2ban-exporter/data
       - name: config-d
         secret:
-          secretName: prometheus-fail2ban-exporter-unittest-web-config
+          secretName: prometheus-fail2ban-exporter-unittest-web-config
+    template: templates/prometheus-fail2ban-exporter/daemonSet.yaml