feat: add more predefined triggers. allow for total flexibility (#67)

Author: domdepasquale

charts/application-core/Chart.yaml

@@ -15,7 +15,7 @@ type: application
 # This is the chart version. This version number should be incremented each time you make changes
 # to the chart and its templates, including the app version.
 # Versions are expected to follow Semantic Versioning (https://semver.org/)
-version: 2.0.1
+version: 3.0.0
 
 maintainers:
   - name: Dominic DePasquale

charts/application-core/templates/scaledobject.yaml

@@ -1,4 +1,4 @@
-{{- if and .Values.autoscaling.enabled (eq .Values.autoscaling.type "scaledobject" ) }}
+{{- if and (and .Values.autoscaling.enabled (eq .Values.autoscaling.type "scaledobject" )) (coalesce .Values.autoscaling.targetMemoryUtilizationPercentage .Values.autoscaling.targetCPUUtilizationPercentage .Values.autoscaling.triggers .Values.autoscaling.kafka .Values.autoscaling.prometheus .Values.autoscaling.cron ) }}
 {{- $fullName := include "application-core.fullname" .  -}}
 apiVersion: keda.sh/v1alpha1
 kind: ScaledObject
@@ -16,18 +16,19 @@ spec:
     apiVersion: apps/v1
     kind: Deployment
     name: {{ include "application-core.fullname" . }}
-  pollingInterval: 30
-  cooldownPeriod: 300
+  pollingInterval: {{ default 30 .Values.autoscaling.pollingInterval }}
+  cooldownPeriod: {{ default 300 .Values.autoscaling.cooldownPeriod }}
   minReplicaCount: {{ .Values.autoscaling.minReplicas }}
   maxReplicaCount: {{ .Values.autoscaling.maxReplicas }}
   triggers:
-    {{- if and .Values.autoscaling.targetCPUUtilizationPercentage (not .Values.autoscaling.kafka )}}
+    {{- if not .Values.autoscaling.triggers -}}
+    {{- if .Values.autoscaling.targetCPUUtilizationPercentage}}
     - type: cpu
       metricType: Utilization
       metadata:
         value: {{ .Values.autoscaling.targetCPUUtilizationPercentage | quote }}
     {{- end }}
-    {{- if and .Values.autoscaling.targetMemoryUtilizationPercentage (not .Values.autoscaling.kafka )}}
+    {{- if .Values.autoscaling.targetMemoryUtilizationPercentage}}
     - type: memory
       metricType: Utilization
       metadata:
@@ -52,4 +53,33 @@ spec:
         kind: {{ default "ClusterTriggerAuthentication" .authenticationRefKind }}
       {{- end }}
     {{- end }}
+    {{- if .Values.autoscaling.prometheus }}
+    - type: prometheus
+      metadata:
+      {{- with .Values.autoscaling.prometheus }}
+        serverAddress: {{ .serverAddress }}
+        query: {{ .query }}
+        threshold: {{ .threshold }}
+        activationThreshold: {{ default 0 .activationThreshold | quote }}
+        ignoreNullValues: {{ default "true" .ignoreNullValues | quote }}
+        unsafeSsl: "false"
+      authenticationRef:
+        name: {{ default "keda-prom-creds" .authenticationRef }}
+        kind: {{ default "ClusterTriggerAuthentication" .authenticationRefKind }}
+      {{- end }}
+    {{- end }}
+    {{- if .Values.autoscaling.cron }}
+    - type: cron
+      metadata:
+      {{- with .Values.autoscaling.cron }}
+        timezone: {{ default "UTC" .timezone }}
+        start: {{ .start }}
+        end: {{ .end }}
+        desiredReplicas: {{ .desiredReplicas }}
+      {{- end }}
+    {{- end }}
+    {{- end }}
+    {{- if .Values.autoscaling.triggers }}
+    {{- toYaml .Values.autoscaling.triggers | nindent 4 }}
+    {{- end }}
 {{- end }}

charts/application-core/values.yaml

@@ -132,13 +132,45 @@ autoscaling:
   type: "scaledobject"  # Can be 'hpa'
   minReplicas: 1
   maxReplicas: 10
-  targetCPUUtilizationPercentage: 80
-  targetMemoryUtilizationPercentage: 80
+
+  # targetCPUUtilizationPercentage: 80
+  # targetMemoryUtilizationPercentage: 80
+
   # kafka:
   #   topic: this-topic
   #   bootstrapServers: this.web.address:9092
   #   username: thisusername
 
+  # prometheus:
+  #   serverAddress: http://prometheus.monitoring.svc.cluster.local:9090
+  #   query: |-
+  #     sum(rate(http_requests_total{job="nginx-ingress"}[1m])) by (namespace)
+  #   threshold: 10.3
+
+  # cron:
+  #   timezone: Asia/Kolkata
+  #   start: 30 * * * *
+  #   end: 45 * * * *
+  #   desiredReplicas: "10"
+
+  # Alternatively, just specify the entire trigger list yourself
+
+  # triggers:
+  #   - type: prometheus
+  #     metadata:
+  #       # Required fields:
+  #       serverAddress: http://<prometheus-host>:9090
+  #       query: sum(rate(http_requests_total{deployment="my-deployment"}[2m])) # Note: query must return a vector/scalar single element response
+  #       threshold: '100.50'
+  #       activationThreshold: '5.5'
+  #   - type: cron
+  #     metadata:
+  #       # Required
+  #       timezone: Asia/Kolkata  # The acceptable values would be a value from the IANA Time Zone Database.
+  #       start: 30 * * * *       # Every hour on the 30th minute
+  #       end: 45 * * * *         # Every hour on the 45th minute
+  #       desiredReplicas: "10"
+
 serviceProfile:
   create: false
   routes: