add autoscaler for nginx (#249)

* add autoscaler for nginx

Signed-off-by: Kevin Labesse <[email protected]>

* typo

Signed-off-by: Kevin Labesse <[email protected]>

Author: eraac

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## master / unreleased
 
+* [FEATURE] Add autoscaler for nginx #249
 * [BUGFIX] Fix nil pointer evaluation when using `ruler.dictonaries` option #242
 * [DEPENDENCY] Update Helm release memcached to v5.15.5 #241
 * [DEPENDENCY] Update Helm release memcached to v5.15.8 #247

README.md

@@ -502,6 +502,12 @@ Kubernetes: `^1.19.0-0`
 | memcached.​resources | object | `{}` |  |
 | nginx.​affinity | object | `{}` |  |
 | nginx.​annotations | object | `{}` |  |
+| nginx.​autoscaling.​behavior | object | `{}` | Ref: https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/#support-for-configurable-scaling-behavior |
+| nginx.​autoscaling.​enabled | bool | `false` | Creates a HorizontalPodAutoscaler for the nginx pods. |
+| nginx.​autoscaling.​maxReplicas | int | `30` |  |
+| nginx.​autoscaling.​minReplicas | int | `2` |  |
+| nginx.​autoscaling.​targetCPUUtilizationPercentage | int | `80` |  |
+| nginx.​autoscaling.​targetMemoryUtilizationPercentage | int | `0` |  |
 | nginx.​config.​auth_orgs | list | `[]` | (optional) List of [auth tenants](https://cortexmetrics.io/docs/guides/auth/) to set in the nginx config |
 | nginx.&ZeroWidthSpace;config.&ZeroWidthSpace;basicAuthSecretName | string | `""` | (optional) Name of basic auth secret. In order to use this option, a secret with htpasswd formatted contents at the key ".htpasswd" must exist. For example:   apiVersion: v1   kind: Secret   metadata:     name: my-secret     namespace: <same as cortex installation>   stringData:     .htpasswd: |       user1:$apr1$/woC1jnP$KAh0SsVn5qeSMjTtn0E9Q0       user2:$apr1$QdR8fNLT$vbCEEzDj7LyqCMyNpSoBh/ Please note that the use of basic auth will not identify organizations the way X-Scope-OrgID does. Thus, the use of basic auth alone will not prevent one tenant from viewing the metrics of another. To ensure tenants are scoped appropriately, explicitly set the `X-Scope-OrgID` header in the nginx config. Example   setHeaders:     X-Scope-Org-Id: $remote_user |
 | nginx.&ZeroWidthSpace;config.&ZeroWidthSpace;client_max_body_size | string | `"1M"` |  |

ci/test-values.yaml

@@ -69,6 +69,8 @@ querier:
     enabled: true
 nginx:
   replicas: 1
+  autoscaling:
+    enabled: true
   config:
     httpSnippet: |-
       # http snippet

templates/nginx/nginx-dep.yaml

@@ -9,7 +9,9 @@ metadata:
   annotations:
     {{- toYaml .Values.nginx.annotations | nindent 4 }}
 spec:
+  {{- if not .Values.nginx.autoscaling.enabled }}
   replicas: {{ .Values.nginx.replicas }}
+  {{- end }}
   selector:
     matchLabels:
       {{- include "cortex.nginxSelectorLabels" . | nindent 6 }}

templates/nginx/nginx-hpa.yaml

@@ -0,0 +1,39 @@
+{{- with .Values.nginx.autoscaling -}}
+{{- if .enabled }}
+apiVersion: autoscaling/v2beta2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "cortex.nginxFullname" $ }}
+  namespace: {{ $.Release.Namespace }}
+  labels:
+    {{- include "cortex.nginxLabels" $ | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: {{ include "cortex.nginxFullname" $ }}
+  minReplicas: {{ .minReplicas }}
+  maxReplicas: {{ .maxReplicas }}
+  metrics:
+  {{- with .targetCPUUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: {{ . }}
+  {{- end }}
+  {{- with .targetMemoryUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: memory
+        target:
+          type: Utilization
+          averageUtilization: {{ . }}
+  {{- end }}
+  {{- with .behavior }}
+  behavior:
+    {{- toYaml . | nindent 4 }}
+  {{- end }}
+{{- end }}
+{{- end }}

values.yaml

@@ -1295,6 +1295,16 @@ nginx:
   extraPorts: []
   env: []
 
+  autoscaling:
+    # -- Creates a HorizontalPodAutoscaler for the nginx pods.
+    enabled: false
+    minReplicas: 2
+    maxReplicas: 30
+    targetCPUUtilizationPercentage: 80
+    targetMemoryUtilizationPercentage: 0  # 80
+    # -- Ref: https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/#support-for-configurable-scaling-behavior
+    behavior: {}
+
 store_gateway:
   replicas: 1