Add a helm chart for fast-cs IOCs

.github/workflows/_helm.yml

@@ -0,0 +1,32 @@
+name: Package helm charts
+
+on:
+  workflow_call:
+
+env:
+  HELM_VERSION_TO_INSTALL: 3.14.3
+
+jobs:
+  package-helm-charts:
+    name: Test helm chart packaging
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Install helm
+        uses: Azure/setup-helm@v3
+        with:
+          version: ${{ env.HELM_VERSION_TO_INSTALL }}
+
+      - name: Package helm charts
+        run: |
+          ./package-helm-chart.sh
+
+      - name: Upload helm charts as artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: charts
+          path: charts

.github/workflows/_release.yml

@@ -20,6 +20,17 @@ jobs:
             rm -rf $GITHUB_REF_NAME
           fi
 
+      - name: Push tagged helm chart to registry
+        run: |
+          set -x
+
+          echo "${{ secrets.GITHUB_TOKEN }}" | helm registry login ghcr.io/${{ github.repository_owner }} --username ${{ github.repository_owner }} --password-stdin
+
+          IFS='@' read -r NAME VERSION <<< "${GITHUB_REF_NAME}"
+          REGISTRY=oci://ghcr.io/diamondlightsource
+
+          helm push "${NAME}-${VERSION}.tgz" ${REGISTRY}
+
       - name: Create GitHub Release
         # We pin to the SHA, not the tag, for security reasons.
         # https://docs.github.com/en/actions/learn-github-actions/security-hardening-for-github-actions#using-third-party-actions

.github/workflows/ci.yml

@@ -51,9 +51,12 @@ jobs:
     permissions:
       id-token: write
 
+  helm:
+    uses: ./.github/workflows/_helm.yml
+
   release:
     if: github.ref_type == 'tag'
-    needs: [dist, docs]
+    needs: [dist, docs, helm]
     uses: ./.github/workflows/_release.yml
     permissions:
       contents: write

.pre-commit-config.yaml

@@ -1,9 +1,10 @@
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.5.0
+    rev: v5.0.0
     hooks:
       - id: check-added-large-files
       - id: check-yaml
+        exclude: ^helm/templates/
       - id: check-merge-conflict
       - id: end-of-file-fixer
 

helm/.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/

helm/Chart.yaml

@@ -0,0 +1,24 @@
+apiVersion: v2
+name: fastcs-instance
+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: "1.16.0"

helm/templates/_helpers.tpl

@@ -0,0 +1,62 @@
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "fastcs.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 "fastcs.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 "fastcs.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Common labels
+*/}}
+{{- define "fastcs.labels" -}}
+helm.sh/chart: {{ include "fastcs.chart" . }}
+{{ include "fastcs.selectorLabels" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}
+
+{{/*
+Selector labels
+*/}}
+{{- define "fastcs.selectorLabels" -}}
+app.kubernetes.io/name: {{ include "fastcs.name" . }}
+app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}
+
+{{/*
+Create the name of the service account to use
+*/}}
+{{- define "fastcs.serviceAccountName" -}}
+{{- if .Values.serviceAccount.create }}
+{{- default (include "fastcs.fullname" .) .Values.serviceAccount.name }}
+{{- else }}
+{{- default "default" .Values.serviceAccount.name }}
+{{- end }}
+{{- end }}

helm/templates/clusterIP.tpl

@@ -0,0 +1,73 @@
+
+{{- define "allocateIpFromName" -}}
+  {{- $name := printf "%s.%s" .name .namespace -}}
+  {{- $baseIpWithCIDR := .baseIp -}}
+
+  {{- $startIp := .startIp | int -}}
+  {{- $conversion := atoi (adler32sum $name) -}}
+
+  {{- $baseIpParts := split "/" $baseIpWithCIDR -}}
+  {{- $baseIp := index $baseIpParts "_0" -}}
+  {{- $cidrRange := index $baseIpParts "_1" | int -}}
+
+  {{- $octets := split "." $baseIp -}}
+  {{- $firstOctet := index $octets "_0" | int -}}
+  {{- $secondOctet := index $octets "_1" | int -}}
+  {{- $thirdOctet := index $octets "_2" | int -}}
+  {{- $fourthOctet := index $octets "_3" | int -}}
+
+
+  {{- $totalIps := 1 }}
+  {{- $loopcnt:= sub 32 $cidrRange -}}
+  {{- range $i,$k := until ($loopcnt | int) }}
+    {{- $totalIps = mul $totalIps 2 }}
+  {{- end }}
+
+  {{- $ipSuffix := add $startIp (mod $conversion $totalIps) -}}
+
+  {{- $secondOctet := add $secondOctet (div $ipSuffix 65536) -}}
+  {{- $ipSuffix = mod $ipSuffix 65536 -}}
+  {{- $thirdOctet := add $thirdOctet (div $ipSuffix 256) -}}
+  {{- $fourthOctet := mod $ipSuffix 256 -}}
+
+  {{- if gt $fourthOctet 255 }}
+    {{- $fourthOctet = mod $fourthOctet 256 -}}
+  {{- end }}
+  {{- if gt $thirdOctet 255 }}
+    {{- $thirdOctet = mod $thirdOctet 256 -}}
+    {{- $secondOctet = add $secondOctet 1 -}}
+  {{- end }}
+  {{- if gt $secondOctet 255 }}
+    {{- $secondOctet = mod $secondOctet 256 -}}
+  {{- end }}
+
+  {{- printf "%d.%d.%d.%d" $firstOctet $secondOctet $thirdOctet $fourthOctet -}}
+{{- end -}}
+
+
+{{- define "allocateIpFromNames" -}}
+  {{- $name := printf "%s.%s" .name .namespace -}}
+  {{- $baseIpWithCIDR := .baseIp -}}
+
+  {{- $startIp := .startIp | int -}}
+  {{- $conversion := atoi (adler32sum $name) -}}
+
+  {{- $baseIpParts := split "/" $baseIpWithCIDR -}}
+  {{- $baseIp := index $baseIpParts "_0" -}}
+  {{- $cidrRange := index $baseIpParts "_1" | int -}}
+
+  {{- $octets := split "." $baseIp -}}
+  {{- $firstOctet := index $octets "_0" | int -}}
+  {{- $secondOctet := index $octets "_1" | int -}}
+  {{- $thirdOctet := index $octets "_2" | int -}}
+  {{- $fourthOctet := index $octets "_3" | int -}}
+
+  {{- $totalIps := 1 }}
+  {{- $loopcnt:= sub 32 $cidrRange -}}
+  {{- range $i,$k := until ($loopcnt | int) }}
+    {{- $totalIps = mul $totalIps 2 }}
+  {{- end }}
+  {{- printf "CIDR %d IPs %d" $cidrRange $totalIps -}}
+
+
+{{- end -}}