HelmYS is a Kubernetes Helm "post renderer" that lets you write your Helm chart templates with YAMLScript.
YAMLScript can be used in combination with Helm's standard Go template syntax or it can replace it entirely.
When YAMLScript is used exclusively, the Helm chart templates are not only simpler and more concise, but they are also valid YAML files (just like the Chart.yaml and values.yaml files). That means they can be processed with any YAML tools, such as being validated with a YAML linter like yamllint.
Template File Comparisons
This is a side by side comparison of the Helm chart template YAML files created by helm create <chart-name> and then converted to use YAMLScript. The left side is the YAMLScript version and the right side is the original Go template version.
ys-chart/templates/serviceaccount.yaml
| go-chart/templates/serviceaccount.yaml
|
--- !yamlscript/v0:
:when Values.serviceAccount.create:
apiVersion: v1
kind: ServiceAccount
metadata:
name:: serviceAccountName
labels:: chart-labels
:when+ Values.serviceAccount.annotations.?::
annotations:: _
automountServiceAccountToken::
Values.serviceAccount.automount
| {{- if .Values.serviceAccount.create -}}
apiVersion: v1
kind: ServiceAccount
metadata:
name: {{ include "go-chart.serviceAccountName" . }}
labels:
{{- include "go-chart.labels" . | nindent 4 }}
{{- with .Values.serviceAccount.annotations }}
annotations:
{{- toYaml . | nindent 4 }}
{{- end }}
automountServiceAccountToken: {{ .Values.serviceAccount.automount }}
{{- end }}
|
| |
ys-chart/templates/service.yaml
| go-chart/templates/service.yaml
|
--- !yamlscript/v0:
apiVersion: v1
kind: Service
metadata:
name:: chart-fullname
labels:: chart-labels
spec:
type:: Values.service.type
ports:
- port:: Values.service.port
targetPort: http
protocol: TCP
name: http
selector:: selectorLabels
| apiVersion: v1
kind: Service
metadata:
name: {{ include "go-chart.fullname" . }}
labels:
{{- include "go-chart.labels" . | nindent 4 }}
spec:
type: {{ .Values.service.type }}
ports:
- port: {{ .Values.service.port }}
targetPort: http
protocol: TCP
name: http
selector:
{{- include "go-chart.selectorLabels" . | nindent 4 }}
|
| |
ys-chart/templates/deployment.yaml
| go-chart/templates/deployment.yaml
|
--- !yamlscript/v0:
apiVersion: apps/v1
kind: Deployment
metadata:
name:: chart-fullname
labels:: chart-labels
spec:
:when-not Values.autoscaling.enabled.?::
replicas:: Values.replicaCount
selector:
matchLabels:: selectorLabels
template:
metadata:
:when+ Values.podAnnotations.?::
annotations:: _
labels:: chart-labels
spec:
:when+ Values.imagePullSecrets.?::
imagePullSecrets:: _
serviceAccountName:: serviceAccountName
securityContext:: Values.podSecurityContext
containers:
- name:: Chart.name
securityContext:: Values.securityContext
image::
"$(Values.image.repository):\
$(Values.image.tag ||| Chart.appVersion)"
imagePullPolicy:: Values.image.pullPolicy
ports:
- name: http
containerPort:: Values.service.port
protocol: TCP
livenessProbe:: Values.livenessProbe
readinessProbe:: Values.readinessProbe
resources:: Values.resources
:when+ Values.volumeMounts.?::
volumeMounts:: _
:when+ Values.volumes.?:: {volumes:: _}
:when+ Values.nodeSelector.?:: {nodeSelector:: _}
:when+ Values.affinity.?:: {affinity:: _}
:when+ Values.tolerations.?:: {tolerations:: _}
| apiVersion: apps/v1
kind: Deployment
metadata:
name: {{ include "go-chart.fullname" . }}
labels:
{{- include "go-chart.labels" . | nindent 4 }}
spec:
{{- if not .Values.autoscaling.enabled }}
replicas: {{ .Values.replicaCount }}
{{- end }}
selector:
matchLabels:
{{- include "go-chart.selectorLabels" . | nindent 6 }}
template:
metadata:
{{- with .Values.podAnnotations }}
annotations:
{{- toYaml . | nindent 8 }}
{{- end }}
labels:
{{- include "go-chart.labels" . | nindent 8 }}
{{- with .Values.podLabels }}
{{- toYaml . | nindent 8 }}
{{- end }}
spec:
{{- with .Values.imagePullSecrets }}
imagePullSecrets:
{{- toYaml . | nindent 8 }}
{{- end }}
serviceAccountName: {{ include "go-chart.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 }}
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 }}
|
| |
ys-chart/templates/helpers.yaml
| go-chart/templates/_helpers.tpl
|
--- !yamlscript/v0
defn trunc(s): take(63 s).str(*).replace(/-$/)
chart-name =:
trunc: Values.nameOverride ||| Chart.name
chart-fullname =:
if Values.fullnameOverride.?:
trunc: Values.fullnameOverride
else:
name =: Values.nameOverride ||| Chart.name
if name.has?(Release.Name):
trunc: Release.Name
format "%s-%s": Release.Name name
selectorLabels =::
app.kubernetes.io/name:: Chart.name
app.kubernetes.io/instance:: Release.Name
chart-labels =::
helm.sh/chart:: "$(Chart.name)-$(Chart.version)"
:: selectorLabels
app.kubernetes.io/version:: Chart.appVersion
app.kubernetes.io/managed-by:: Release.Service
serviceAccountName =:
Values.serviceAccount.name |||:
if Values.serviceAccount.create:
chart-fullname
'default'
| {{/*
Expand the name of the chart.
*/}}
{{- define "go-chart.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 "go-chart.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 "go-chart.chart" -}}
{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 |
trimSuffix "-" }}
{{- end }}
{{/*
Common labels
*/}}
{{- define "go-chart.labels" -}}
helm.sh/chart: {{ include "go-chart.chart" . }}
{{ include "go-chart.selectorLabels" . }}
{{- if .Chart.AppVersion }}
app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
{{- end }}
app.kubernetes.io/managed-by: {{ .Release.Service }}
{{- end }}
{{/*
Selector labels
*/}}
{{- define "go-chart.selectorLabels" -}}
app.kubernetes.io/name: {{ include "go-chart.name" . }}
app.kubernetes.io/instance: {{ .Release.Name }}
{{- end }}
{{/*
Create the name of the service account to use
*/}}
{{- define "go-chart.serviceAccountName" -}}
{{- if .Values.serviceAccount.create }}
{{- default (include "go-chart.fullname" .) .Values.serviceAccount.name }}
{{- else }}
{{- default "default" .Values.serviceAccount.name }}
{{- end }}
{{- end }}
|
