common/README.md

Getting Started

Adding Repository

The following command allows you to download and install all the charts from our repository:

$ helm repo add hahow oci://cr.grachevko.ru/helm/chart

Adding Dependency

To use the library chart, common should be listed in dependencies field in your Chart.yaml:

dependencies:
  - name: common
    version: 0.4.1
    repository: oci://cr.grachevko.ru/helm/chart

Once you have defined dependencies, you should run the following command to download this chart into your charts/ directory:

$ helm dep build

Using Starter

The best way to get started is to use the create script to generate a new chart.

You can fetch that script, and then execute it locally:

$ curl https://git.grachevko.ru/helm/common/raw/branch/master/create.sh | bash -s -- mychart

Now, there is a chart in ./mychart. You can edit it and create your own templates.

Partial Objects

When writing Kubernetes resources, you may find the following helpers useful to construct parts of the spec.

common.chart

The common.chart helper prints the chart name and version, escaped to be legal in a Kubernetes label field.

Example template:

helm.sh/chart: { { include "common.chart" . } }

For the chart foo with version 1.2.3-beta.55+1234, this will render:

helm.sh/chart: foo-1.2.3-beta.55_1234

(Note that + is an illegal character in label values)

common.fullname

The common.fullname template generates a name suitable for the name: field in Kubernetes metadata. It is used like this:

name: { { include "common.fullname" . } }

This prints the value of {{ .Release.Name }}-{{ .Chart.Name }} by default, but can be overridden with .Values. fullnameOverride:

fullnameOverride: some-name

Example output:

---
# with the values above
name: some-name

---
# the default, for release "release-name" and chart "mychart"
name: release-name-mychart

Output of this function is truncated at 63 characters, which is the maximum length of name.

common.labels

common.selectorLabels prints the standard set of labels.

Example usage:

{{ include "common.labels" . }}

Example output:

app.kubernetes.io/instance: release-name
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/name: mychart
app.kubernetes.io/version: 1.16.0
helm.sh/chart: mychart-0.1.0

common.metadata

The common.metadata helper generates value for the metadata: section of a Kubernetes resource.

This takes a list of two values:

• $top, the top context
• [optional] the template name of the overrides

It generates standard labels and a name field.

Example template:

metadata: { { - include "common.metadata" (list .) | nindent 2 } }
## The following is the same as above:
# metadata:
#   {{- include "common.metadata" (list . "mychart.metadata") | nindent 2 }}
# {{- define "mychart.metadata" -}}
# {{- end }}

Example output:

metadata:
  labels:
    app.kubernetes.io/instance: release-name
    app.kubernetes.io/managed-by: Helm
    app.kubernetes.io/name: mychart
    app.kubernetes.io/version: 1.16.0
    helm.sh/chart: mychart-0.1.0
  name: release-name-mychart

Most of the common templates that define a resource type (e.g. common.configMap or common.cronJob) use this to generate the metadata, which means they inherit the same labels and name fields.

common.name

The common.name template generates a name suitable for the app.kubernetes.io/name label. It is used like this:

app.kubernetes.io/name: { { include "common.name" . } }

This prints the value of {{ .Chart.Name }} by default, but can be overridden with .Values.nameOverride:

nameOverride: some-name

Example output:

---
# with the values above
app.kubernetes.io/name: some-name

---
# the default, for chart "mychart"
app.kubernetes.io/name: mychart

Output of this function is truncated at 63 characters, which is the maximum length of name.

common.selectorLabels

common.selectorLabels prints the standard set of selector labels.

Example usage:

{{ include "common.selectorLabels" . }}

Example output:

app.kubernetes.io/instance: release-name
app.kubernetes.io/name: mychart