Add Helm chart for calibre-web deployment

This commit introduces a new Helm chart for deploying calibre-web
on Kubernetes. The chart includes essential templates for
deployment, service, ingress, and persistent volume claims, along
with default values configured in a `values.yaml` file.

The addition of the Helm chart enables easier deployment and
management of calibre-web, allowing users to customize settings
like the replica count, image settings, service type, and storage
options through the `values.yaml`. A GitHub Actions workflow
(`build-chart-calibre-web.yml`) is also included to automate the
packaging and uploading of the Helm chart upon updates to the
main branch.

The structure and organization of the templates adhere to Helm
best practices, ensuring compatibility and ease of use. There are no
breaking changes associated with this addition, but users should
review the `values.yaml` for configurable options.

charts/cailbre-web/templates/NOTES.txt

@@ -0,0 +1,18 @@
+1. Get the application URL by running these commands:
+{{- if .Values.ingress.enabled }}
+{{- range $host := .Values.ingress.hosts }}
+{{- end }}
+{{- else if contains "NodePort" .Values.service.type }}
+  export NODE_PORT=$(kubectl get --namespace {{ .Release.Namespace }} -o jsonpath="{.spec.ports[0].nodePort}" services {{ include "calibre-web.fullname" . }})
+  export NODE_IP=$(kubectl get nodes --namespace {{ .Release.Namespace }} -o jsonpath="{.items[0].status.addresses[0].address}")
+  echo http://$NODE_IP:$NODE_PORT
+{{- else if contains "LoadBalancer" .Values.service.type }}
+     NOTE: It may take a few minutes for the LoadBalancer IP to be available.
+           You can watch the status of by running 'kubectl get --namespace {{ .Release.Namespace }} svc -w {{ include "calibre-web.fullname" . }}'
+  export SERVICE_IP=$(kubectl get svc --namespace {{ .Release.Namespace }} {{ include "calibre-web.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 "calibre-web.name" . }},app.kubernetes.io/instance={{ .Release.Name }}" -o jsonpath="{.items[0].metadata.name}")
+  echo "Visit http://127.0.0.1:8080 to use your application"
+  kubectl --namespace {{ .Release.Namespace }} port-forward $POD_NAME 8080:80
+{{- end }}

charts/cailbre-web/templates/_helpers.tpl

@@ -0,0 +1,63 @@
+{{/* vim: set filetype=mustache: */}}
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "calibre-web.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 "calibre-web.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 "calibre-web.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" -}}
+{{- end -}}
+
+{{/*
+Common labels
+*/}}
+{{- define "calibre-web.labels" -}}
+helm.sh/chart: {{ include "calibre-web.chart" . }}
+{{ include "calibre-web.selectorLabels" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end -}}
+
+{{/*
+Selector labels
+*/}}
+{{- define "calibre-web.selectorLabels" -}}
+app.kubernetes.io/name: {{ include "calibre-web.name" . }}
+app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end -}}
+
+{{/*
+Create the name of the service account to use
+*/}}
+{{- define "calibre-web.serviceAccountName" -}}
+{{- if .Values.serviceAccount.create -}}
+    {{ default (include "calibre-web.fullname" .) .Values.serviceAccount.name }}
+{{- else -}}
+    {{ default "default" .Values.serviceAccount.name }}
+{{- end -}}
+{{- end -}}

charts/cailbre-web/templates/deployment.yaml

@@ -0,0 +1,91 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "calibre-web.fullname" . }}
+  labels:
+    {{- include "calibre-web.labels" . | nindent 4 }}
+  {{- with .Values.annotations }}
+  annotations:
+      {{- toYaml . | nindent 4 }}
+  {{- end }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "calibre-web.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      labels:
+        {{- include "calibre-web.selectorLabels" . | nindent 8 }}
+      {{- with .Values.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+    spec:
+    {{- with .Values.imagePullSecrets }}
+      imagePullSecrets:
+        {{- toYaml . | nindent 8 }}
+    {{- end }}
+      serviceAccountName: {{ include "calibre-web.serviceAccountName" . }}
+      securityContext:
+        {{- toYaml .Values.podSecurityContext | nindent 8 }}
+      containers:
+        - name: {{ .Chart.Name }}
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
+          image: "{{ .Values.image.repository }}:{{ .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          env:
+            {{ toYaml .Values.env | nindent 12 }}
+          ports:
+            - name: http
+              containerPort: 8083
+              protocol: TCP
+          startupProbe:
+            httpGet:
+              path: /
+              port: http
+            failureThreshold: 30
+            periodSeconds: 5
+          livenessProbe:
+            httpGet:
+              path: /
+              port: http
+          readinessProbe:
+            httpGet:
+              path: /
+              port: http
+          volumeMounts:
+          - name: data
+            mountPath: /books
+          - name: config
+            mountPath: /config
+          resources:
+            {{- toYaml .Values.resources | nindent 12 }}
+      volumes:
+      - name: data
+        persistentVolumeClaim:
+    {{- if .Values.persistence.data.claimName }}
+          claimName: "{{ .Values.persistence.data.claimName }}"
+    {{- else }}
+          claimName: "{{ template "calibre-web.fullname" . }}-data"
+    {{- end }}
+      - name: config
+        persistentVolumeClaim:
+    {{- if .Values.persistence.config.claimName }}
+          claimName: "{{ .Values.persistence.config.claimName }}"
+    {{- else }}
+          claimName: "{{ template "calibre-web.fullname" . }}-config"
+    {{- 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 }}

charts/cailbre-web/templates/ingress.yaml

@@ -0,0 +1,64 @@
+{{- if .Values.ingress.enabled }}
+{{- $fullName := "calibre-web" -}}
+{{- $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:
+    app.kubernetes.io/name: excalidraw
+    app.kubernetes.io/instance: {{ .Release.Name | quote }}
+    app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+    app.kubernetes.io/managed-by: {{ .Release.Service | quote }}
+  {{- 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 }}

charts/cailbre-web/templates/service.yaml

@@ -0,0 +1,15 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ include "calibre-web.fullname" . }}
+  labels:
+    {{- include "calibre-web.labels" . | nindent 4 }}
+spec:
+  type: {{ .Values.service.type }}
+  ports:
+    - port: {{ .Values.service.port }}
+      targetPort: http
+      protocol: TCP
+      name: http
+  selector:
+    {{- include "calibre-web.selectorLabels" . | nindent 4 }}

charts/cailbre-web/templates/serviceaccount.yaml

@@ -0,0 +1,8 @@
+{{- if .Values.serviceAccount.create -}}
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: {{ include "calibre-web.serviceAccountName" . }}
+  labels:
+{{ include "calibre-web.labels" . | nindent 4 }}
+{{- end -}}

charts/cailbre-web/templates/tests/test-connection.yaml

@@ -0,0 +1,15 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: "{{ include "calibre-web.fullname" . }}-test-connection"
+  labels:
+{{ include "calibre-web.labels" . | nindent 4 }}
+  annotations:
+    "helm.sh/hook": test-success
+spec:
+  containers:
+    - name: wget
+      image: busybox
+      command: ['wget']
+      args:  ['{{ include "calibre-web.fullname" . }}:{{ .Values.service.port }}']
+  restartPolicy: Never

charts/cailbre-web/templates/volumes.yaml

@@ -0,0 +1,44 @@
+{{- if not .Values.persistence.config.claimName }}
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: {{ template "calibre-web.fullname" . }}-config
+  labels:
+    app: {{ template "calibre-web.name" . }}
+    chart: {{ .Chart.Name }}-{{ .Chart.Version | replace "+" "_" }}
+    release: {{ .Release.Name }}
+    heritage: {{ .Release.Service }}
+    component: config
+spec:
+  accessModes:
+  - ReadWriteMany
+  resources:
+    requests:
+      storage: {{ .Values.persistence.config.size | quote }}
+{{- if .Values.persistence.config.storageClass }}
+  storageClassName: {{ .Values.persistence.config.storageClass | quote }}
+{{- end }}
+---
+{{- end }}
+{{- if not .Values.persistence.data.claimName }}
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: {{ template "calibre-web.fullname" . }}-data
+  labels:
+    app: {{ template "calibre-web.name" . }}
+    chart: {{ .Chart.Name }}-{{ .Chart.Version | replace "+" "_" }}
+    release: {{ .Release.Name }}
+    heritage: {{ .Release.Service }}
+    component: data
+spec:
+  accessModes:
+  - ReadWriteMany
+  resources:
+    requests:
+      storage: {{ .Values.persistence.data.size | quote }}
+{{- if .Values.persistence.data.storageClass }}
+  storageClassName: {{ .Values.persistence.data.storageClass | quote }}
+{{- end }}
+---
+{{- end }}