From 2bdebd9014979064a1578b0128555bbccd7df7fa Mon Sep 17 00:00:00 2001 From: Gabriel Radureau Date: Sun, 29 Sep 2024 17:54:23 +0200 Subject: [PATCH] add helm chart with readiness endpoint --- .gitea/workflows/dockerimage.yaml | 2 +- README.md | 2 +- chart/.helmignore | 23 +++++ chart/Chart.yaml | 24 +++++ chart/templates/NOTES.txt | 22 ++++ chart/templates/_helpers.tpl | 62 ++++++++++++ chart/templates/config.yaml | 8 ++ chart/templates/deployment.yaml | 71 +++++++++++++ chart/templates/hpa.yaml | 32 ++++++ chart/templates/ingress.yaml | 61 +++++++++++ chart/templates/service.yaml | 15 +++ chart/templates/serviceaccount.yaml | 13 +++ chart/templates/tests/test-connection.yaml | 15 +++ chart/values.yaml | 111 +++++++++++++++++++++ main.go | 32 +++++- 15 files changed, 488 insertions(+), 5 deletions(-) create mode 100644 chart/.helmignore create mode 100644 chart/Chart.yaml create mode 100644 chart/templates/NOTES.txt create mode 100644 chart/templates/_helpers.tpl create mode 100644 chart/templates/config.yaml create mode 100644 chart/templates/deployment.yaml create mode 100644 chart/templates/hpa.yaml create mode 100644 chart/templates/ingress.yaml create mode 100644 chart/templates/service.yaml create mode 100644 chart/templates/serviceaccount.yaml create mode 100644 chart/templates/tests/test-connection.yaml create mode 100644 chart/values.yaml diff --git a/.gitea/workflows/dockerimage.yaml b/.gitea/workflows/dockerimage.yaml index 6cb3128..c46725b 100644 --- a/.gitea/workflows/dockerimage.yaml +++ b/.gitea/workflows/dockerimage.yaml @@ -8,7 +8,7 @@ on: - main paths-ignore: - 'README.md' - - 'argocd/**' + - 'chart/**' # cancel any previously-started, yet still active runs of this workflow on the same branch concurrency: group: ${{ github.ref }}-${{ github.workflow }} diff --git a/README.md b/README.md index 2275899..b8c84ab 100644 --- a/README.md +++ b/README.md @@ -6,5 +6,5 @@ return 42 + the number in input > [!NOTE] > code generated with chat gpt -- [ ] Connect through pgbouncer +- [x] Connect through pgbouncer - [ ] Credentials generated with Hashicorp Vault \ No newline at end of file diff --git a/chart/.helmignore b/chart/.helmignore new file mode 100644 index 0000000..0e8a0eb --- /dev/null +++ b/chart/.helmignore @@ -0,0 +1,23 @@ +# Patterns to ignore when building packages. +# This supports shell glob matching, relative path matching, and +# negation (prefixed with !). Only one pattern per line. +.DS_Store +# Common VCS dirs +.git/ +.gitignore +.bzr/ +.bzrignore +.hg/ +.hgignore +.svn/ +# Common backup files +*.swp +*.bak +*.tmp +*.orig +*~ +# Various IDEs +.project +.idea/ +*.tmproj +.vscode/ diff --git a/chart/Chart.yaml b/chart/Chart.yaml new file mode 100644 index 0000000..ab53ee3 --- /dev/null +++ b/chart/Chart.yaml @@ -0,0 +1,24 @@ +apiVersion: v2 +name: webapp +description: A Helm chart for Kubernetes + +# A chart can be either an 'application' or a 'library' chart. +# +# Application charts are a collection of templates that can be packaged into versioned archives +# to be deployed. +# +# Library charts provide useful utilities or functions for the chart developer. They're included as +# a dependency of application charts to inject those utilities and functions into the rendering +# pipeline. Library charts do not define any templates and therefore cannot be deployed. +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: 0.1.0 + +# This is the version number of the application being deployed. This version number should be +# incremented each time you make changes to the application. Versions are not expected to +# follow Semantic Versioning. They should reflect the version the application is using. +# It is recommended to use it with quotes. +appVersion: "latest" diff --git a/chart/templates/NOTES.txt b/chart/templates/NOTES.txt new file mode 100644 index 0000000..16ff3a5 --- /dev/null +++ b/chart/templates/NOTES.txt @@ -0,0 +1,22 @@ +1. Get the application URL by running these commands: +{{- if .Values.ingress.enabled }} +{{- range $host := .Values.ingress.hosts }} + {{- range .paths }} + http{{ if $.Values.ingress.tls }}s{{ end }}://{{ $host.host }}{{ .path }} + {{- end }} +{{- end }} +{{- else if contains "NodePort" .Values.service.type }} + export NODE_PORT=$(kubectl get --namespace {{ .Release.Namespace }} -o jsonpath="{.spec.ports[0].nodePort}" services {{ include "webapp.fullname" . }}) + export NODE_IP=$(kubectl get nodes --namespace {{ .Release.Namespace }} -o jsonpath="{.items[0].status.addresses[0].address}") + echo http://$NODE_IP:$NODE_PORT +{{- else if contains "LoadBalancer" .Values.service.type }} + NOTE: It may take a few minutes for the LoadBalancer IP to be available. + You can watch its status by running 'kubectl get --namespace {{ .Release.Namespace }} svc -w {{ include "webapp.fullname" . }}' + export SERVICE_IP=$(kubectl get svc --namespace {{ .Release.Namespace }} {{ include "webapp.fullname" . }} --template "{{"{{ range (index .status.loadBalancer.ingress 0) }}{{.}}{{ end }}"}}") + echo http://$SERVICE_IP:{{ .Values.service.port }} +{{- else if contains "ClusterIP" .Values.service.type }} + export POD_NAME=$(kubectl get pods --namespace {{ .Release.Namespace }} -l "app.kubernetes.io/name={{ include "webapp.name" . }},app.kubernetes.io/instance={{ .Release.Name }}" -o jsonpath="{.items[0].metadata.name}") + export CONTAINER_PORT=$(kubectl get pod --namespace {{ .Release.Namespace }} $POD_NAME -o jsonpath="{.spec.containers[0].ports[0].containerPort}") + echo "Visit http://127.0.0.1:8080 to use your application" + kubectl --namespace {{ .Release.Namespace }} port-forward $POD_NAME 8080:$CONTAINER_PORT +{{- end }} diff --git a/chart/templates/_helpers.tpl b/chart/templates/_helpers.tpl new file mode 100644 index 0000000..db550e5 --- /dev/null +++ b/chart/templates/_helpers.tpl @@ -0,0 +1,62 @@ +{{/* +Expand the name of the chart. +*/}} +{{- define "webapp.name" -}} +{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }} +{{- end }} + +{{/* +Create a default fully qualified app name. +We truncate at 63 chars because some Kubernetes name fields are limited to this (by the DNS naming spec). +If release name contains chart name it will be used as a full name. +*/}} +{{- define "webapp.fullname" -}} +{{- if .Values.fullnameOverride }} +{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }} +{{- else }} +{{- $name := default .Chart.Name .Values.nameOverride }} +{{- if contains $name .Release.Name }} +{{- .Release.Name | trunc 63 | trimSuffix "-" }} +{{- else }} +{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }} +{{- end }} +{{- end }} +{{- end }} + +{{/* +Create chart name and version as used by the chart label. +*/}} +{{- define "webapp.chart" -}} +{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }} +{{- end }} + +{{/* +Common labels +*/}} +{{- define "webapp.labels" -}} +helm.sh/chart: {{ include "webapp.chart" . }} +{{ include "webapp.selectorLabels" . }} +{{- if .Chart.AppVersion }} +app.kubernetes.io/version: {{ .Chart.AppVersion | quote }} +{{- end }} +app.kubernetes.io/managed-by: {{ .Release.Service }} +{{- end }} + +{{/* +Selector labels +*/}} +{{- define "webapp.selectorLabels" -}} +app.kubernetes.io/name: {{ include "webapp.name" . }} +app.kubernetes.io/instance: {{ .Release.Name }} +{{- end }} + +{{/* +Create the name of the service account to use +*/}} +{{- define "webapp.serviceAccountName" -}} +{{- if .Values.serviceAccount.create }} +{{- default (include "webapp.fullname" .) .Values.serviceAccount.name }} +{{- else }} +{{- default "default" .Values.serviceAccount.name }} +{{- end }} +{{- end }} diff --git a/chart/templates/config.yaml b/chart/templates/config.yaml new file mode 100644 index 0000000..71f5d50 --- /dev/null +++ b/chart/templates/config.yaml @@ -0,0 +1,8 @@ +apiVersion: v1 +kind: ConfigMap +metadata: + name: {{ include "webapp.name" . }}-config + namespace: {{ .Release.Namespace }} +data: + DATABASE_URL: postgres://pgbouncer_auth:pgbouncer_auth@pgbouncer.tools/postgres?sslmode=disable +# DATABASE_URL: postgres://username:password@localhost/dbname?sslmode=disable \ No newline at end of file diff --git a/chart/templates/deployment.yaml b/chart/templates/deployment.yaml new file mode 100644 index 0000000..fb3ec0b --- /dev/null +++ b/chart/templates/deployment.yaml @@ -0,0 +1,71 @@ +apiVersion: apps/v1 +kind: Deployment +metadata: + name: {{ include "webapp.fullname" . }} + labels: + {{- include "webapp.labels" . | nindent 4 }} +spec: + {{- if not .Values.autoscaling.enabled }} + replicas: {{ .Values.replicaCount }} + {{- end }} + selector: + matchLabels: + {{- include "webapp.selectorLabels" . | nindent 6 }} + template: + metadata: + {{- with .Values.podAnnotations }} + annotations: + {{- toYaml . | nindent 8 }} + {{- end }} + labels: + {{- include "webapp.labels" . | nindent 8 }} + {{- with .Values.podLabels }} + {{- toYaml . | nindent 8 }} + {{- end }} + spec: + {{- with .Values.imagePullSecrets }} + imagePullSecrets: + {{- toYaml . | nindent 8 }} + {{- end }} + serviceAccountName: {{ include "webapp.serviceAccountName" . }} + securityContext: + {{- toYaml .Values.podSecurityContext | nindent 8 }} + containers: + - name: {{ .Chart.Name }} + securityContext: + {{- toYaml .Values.securityContext | nindent 12 }} + image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}" + imagePullPolicy: {{ .Values.image.pullPolicy }} + envFrom: + - configMapRef: + name: {{ include "webapp.name" . }}-config + ports: + - name: http + containerPort: {{ .Values.service.port }} + protocol: TCP + livenessProbe: + {{- toYaml .Values.livenessProbe | nindent 12 }} + readinessProbe: + {{- toYaml .Values.readinessProbe | nindent 12 }} + resources: + {{- toYaml .Values.resources | nindent 12 }} + {{- with .Values.volumeMounts }} + volumeMounts: + {{- toYaml . | nindent 12 }} + {{- end }} + {{- with .Values.volumes }} + volumes: + {{- toYaml . | nindent 8 }} + {{- end }} + {{- with .Values.nodeSelector }} + nodeSelector: + {{- toYaml . | nindent 8 }} + {{- end }} + {{- with .Values.affinity }} + affinity: + {{- toYaml . | nindent 8 }} + {{- end }} + {{- with .Values.tolerations }} + tolerations: + {{- toYaml . | nindent 8 }} + {{- end }} diff --git a/chart/templates/hpa.yaml b/chart/templates/hpa.yaml new file mode 100644 index 0000000..7a67db9 --- /dev/null +++ b/chart/templates/hpa.yaml @@ -0,0 +1,32 @@ +{{- if .Values.autoscaling.enabled }} +apiVersion: autoscaling/v2 +kind: HorizontalPodAutoscaler +metadata: + name: {{ include "webapp.fullname" . }} + labels: + {{- include "webapp.labels" . | nindent 4 }} +spec: + scaleTargetRef: + apiVersion: apps/v1 + kind: Deployment + name: {{ include "webapp.fullname" . }} + minReplicas: {{ .Values.autoscaling.minReplicas }} + maxReplicas: {{ .Values.autoscaling.maxReplicas }} + metrics: + {{- if .Values.autoscaling.targetCPUUtilizationPercentage }} + - type: Resource + resource: + name: cpu + target: + type: Utilization + averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }} + {{- end }} + {{- if .Values.autoscaling.targetMemoryUtilizationPercentage }} + - type: Resource + resource: + name: memory + target: + type: Utilization + averageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }} + {{- end }} +{{- end }} diff --git a/chart/templates/ingress.yaml b/chart/templates/ingress.yaml new file mode 100644 index 0000000..389bb8f --- /dev/null +++ b/chart/templates/ingress.yaml @@ -0,0 +1,61 @@ +{{- if .Values.ingress.enabled -}} +{{- $fullName := include "webapp.fullname" . -}} +{{- $svcPort := .Values.service.port -}} +{{- if and .Values.ingress.className (not (semverCompare ">=1.18-0" .Capabilities.KubeVersion.GitVersion)) }} + {{- if not (hasKey .Values.ingress.annotations "kubernetes.io/ingress.class") }} + {{- $_ := set .Values.ingress.annotations "kubernetes.io/ingress.class" .Values.ingress.className}} + {{- end }} +{{- end }} +{{- if semverCompare ">=1.19-0" .Capabilities.KubeVersion.GitVersion -}} +apiVersion: networking.k8s.io/v1 +{{- else if semverCompare ">=1.14-0" .Capabilities.KubeVersion.GitVersion -}} +apiVersion: networking.k8s.io/v1beta1 +{{- else -}} +apiVersion: extensions/v1beta1 +{{- end }} +kind: Ingress +metadata: + name: {{ $fullName }} + labels: + {{- include "webapp.labels" . | nindent 4 }} + {{- with .Values.ingress.annotations }} + annotations: + {{- toYaml . | nindent 4 }} + {{- end }} +spec: + {{- if and .Values.ingress.className (semverCompare ">=1.18-0" .Capabilities.KubeVersion.GitVersion) }} + ingressClassName: {{ .Values.ingress.className }} + {{- end }} + {{- if .Values.ingress.tls }} + tls: + {{- range .Values.ingress.tls }} + - hosts: + {{- range .hosts }} + - {{ . | quote }} + {{- end }} + secretName: {{ .secretName }} + {{- end }} + {{- end }} + rules: + {{- range .Values.ingress.hosts }} + - host: {{ .host | quote }} + http: + paths: + {{- range .paths }} + - path: {{ .path }} + {{- if and .pathType (semverCompare ">=1.18-0" $.Capabilities.KubeVersion.GitVersion) }} + pathType: {{ .pathType }} + {{- end }} + backend: + {{- if semverCompare ">=1.19-0" $.Capabilities.KubeVersion.GitVersion }} + service: + name: {{ $fullName }} + port: + number: {{ $svcPort }} + {{- else }} + serviceName: {{ $fullName }} + servicePort: {{ $svcPort }} + {{- end }} + {{- end }} + {{- end }} +{{- end }} diff --git a/chart/templates/service.yaml b/chart/templates/service.yaml new file mode 100644 index 0000000..4ede09a --- /dev/null +++ b/chart/templates/service.yaml @@ -0,0 +1,15 @@ +apiVersion: v1 +kind: Service +metadata: + name: {{ include "webapp.fullname" . }} + labels: + {{- include "webapp.labels" . | nindent 4 }} +spec: + type: {{ .Values.service.type }} + ports: + - port: {{ .Values.service.port }} + targetPort: http + protocol: TCP + name: http + selector: + {{- include "webapp.selectorLabels" . | nindent 4 }} diff --git a/chart/templates/serviceaccount.yaml b/chart/templates/serviceaccount.yaml new file mode 100644 index 0000000..5e83f35 --- /dev/null +++ b/chart/templates/serviceaccount.yaml @@ -0,0 +1,13 @@ +{{- if .Values.serviceAccount.create -}} +apiVersion: v1 +kind: ServiceAccount +metadata: + name: {{ include "webapp.serviceAccountName" . }} + labels: + {{- include "webapp.labels" . | nindent 4 }} + {{- with .Values.serviceAccount.annotations }} + annotations: + {{- toYaml . | nindent 4 }} + {{- end }} +automountServiceAccountToken: {{ .Values.serviceAccount.automount }} +{{- end }} diff --git a/chart/templates/tests/test-connection.yaml b/chart/templates/tests/test-connection.yaml new file mode 100644 index 0000000..1bd5720 --- /dev/null +++ b/chart/templates/tests/test-connection.yaml @@ -0,0 +1,15 @@ +apiVersion: v1 +kind: Pod +metadata: + name: "{{ include "webapp.fullname" . }}-test-connection" + labels: + {{- include "webapp.labels" . | nindent 4 }} + annotations: + "helm.sh/hook": test +spec: + containers: + - name: wget + image: busybox + command: ['wget'] + args: ['{{ include "webapp.fullname" . }}:{{ .Values.service.port }}'] + restartPolicy: Never diff --git a/chart/values.yaml b/chart/values.yaml new file mode 100644 index 0000000..f5acb04 --- /dev/null +++ b/chart/values.yaml @@ -0,0 +1,111 @@ +# Default values for webapp. +# This is a YAML-formatted file. +# Declare variables to be passed into your templates. + +replicaCount: 1 + +image: + repository: gitea.arcodange.duckdns.org/arcodange-org/webapp + pullPolicy: IfNotPresent + # Overrides the image tag whose default is the chart appVersion. + tag: "" + +imagePullSecrets: [] +nameOverride: "" +fullnameOverride: "" + +serviceAccount: + # Specifies whether a service account should be created + create: false + # Automatically mount a ServiceAccount's API credentials? + automount: true + # Annotations to add to the service account + annotations: {} + # The name of the service account to use. + # If not set and create is true, a name is generated using the fullname template + name: "" + +podAnnotations: {} +podLabels: {} + +podSecurityContext: {} + # fsGroup: 2000 + +securityContext: {} + # capabilities: + # drop: + # - ALL + # readOnlyRootFilesystem: true + # runAsNonRoot: true + # runAsUser: 1000 + +service: + type: ClusterIP + port: 8080 + +ingress: + enabled: true + className: "" + annotations: + traefik.ingress.kubernetes.io/router.entrypoints: websecure + traefik.ingress.kubernetes.io/router.tls: "true" + traefik.ingress.kubernetes.io/router.tls.certresolver: letsencrypt + traefik.ingress.kubernetes.io/router.tls.domains.0.main: arcodange.duckdns.org + traefik.ingress.kubernetes.io/router.tls.domains.0.sans: webapp.arcodange.duckdns.org + traefik.ingress.kubernetes.io/router.middlewares: localIp@file + hosts: + - host: webapp.arcodange.duckdns.org + paths: + - path: / + pathType: Prefix + tls: [] + # - secretName: chart-example-tls + # hosts: + # - chart-example.local + +resources: {} + # We usually recommend not to specify default resources and to leave this as a conscious + # choice for the user. This also increases chances charts run on environments with little + # resources, such as Minikube. If you do want to specify resources, uncomment the following + # lines, adjust them as necessary, and remove the curly braces after 'resources:'. + # limits: + # cpu: 100m + # memory: 128Mi + # requests: + # cpu: 100m + # memory: 128Mi + +livenessProbe: + httpGet: + path: /liveness + port: http +readinessProbe: + httpGet: + path: /readiness + port: http + +autoscaling: + enabled: false + minReplicas: 1 + maxReplicas: 100 + targetCPUUtilizationPercentage: 80 + # targetMemoryUtilizationPercentage: 80 + +# Additional volumes on the output Deployment definition. +volumes: [] +# - name: foo +# secret: +# secretName: mysecret +# optional: false + +# Additional volumeMounts on the output Deployment definition. +volumeMounts: [] +# - name: foo +# mountPath: "/etc/foo" +# readOnly: true + +nodeSelector: {} + +tolerations: [] + +affinity: {} diff --git a/main.go b/main.go index a7aa587..ea22264 100644 --- a/main.go +++ b/main.go @@ -3,7 +3,6 @@ package main import ( "database/sql" "fmt" - "html/template" "log" "net/http" "os" @@ -20,6 +19,28 @@ func dbConnection() (*sql.DB, error) { return sql.Open("postgres", connStr) } +// livenessHandler is used by Kubernetes to check if the app is alive. +func livenessHandler(w http.ResponseWriter, r *http.Request) { + w.WriteHeader(http.StatusOK) + fmt.Fprintf(w, "OK") +} + +// readinessHandler is used by Kubernetes to check if the app is ready to serve traffic. +func readinessHandler(w http.ResponseWriter, r *http.Request) { + // Check if the database connection is alive + err := db.Ping() + if err != nil { + log.Printf("Readiness probe failed: Database connection error: %v", err) + w.WriteHeader(http.StatusServiceUnavailable) + fmt.Fprintf(w, "NOT READY") + return + } + + // If the database is reachable, return 200 OK + w.WriteHeader(http.StatusOK) + fmt.Fprintf(w, "OK") +} + // indexHandler serves the HTML form for the query. func indexHandler(w http.ResponseWriter, r *http.Request) { tmpl := ` @@ -70,8 +91,7 @@ func indexHandler(w http.ResponseWriter, r *http.Request) { ` - t := template.Must(template.New("form").Parse(tmpl)) - t.Execute(w, nil) + fmt.Fprintf(w, tmpl) } // selectHandler handles HTTP requests and executes a SQL query. @@ -122,6 +142,12 @@ func main() { // Define the handler for the `/query` route (executes SQL query) http.HandleFunc("/query", selectHandler) + // Define the handler for the `/liveness` probe + http.HandleFunc("/liveness", livenessHandler) + + // Define the handler for the `/readiness` probe + http.HandleFunc("/readiness", readinessHandler) + // Start the HTTP server port := ":8080" log.Printf("Server starting on port %s\n", port)