Namespaces and Names

Working with Namespaces and Names

The Namespace can be set for all Resources in a project by adding the namespace entry to the kustomization.yaml file. Consistent naming conventions can be applied to Resource Names in a project with the namePrefix and nameSuffix fields.

Working with Namespaces

namespace sets the Namespace for all namespaced Resources in a project. This sets the Namespace for both generated Resources (e.g. ConfigMaps and Secrets) and non-generated Resources. This will override Namespace values that already exist.

Add Namespace

Here is an example of how to set the Namespace of a Deployment and a generated ConfigMap. The ConfigMap is generated with configMapGenerator.

  1. Create a Kustomization file.
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namespace: my-namespace

configMapGenerator:
- name: my-config
  literals:
  - FOO=BAR

resources:
- deploy.yaml
  1. Create a Deployment manifest.
# deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: example
  1. Add Namespace with kustomize build.
kustomize build .

The output shows that the namespace field is used to set the Namespace of the Deployment and the generated ConfigMap.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: example
  namespace: my-namespace
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: my-config-m2mg5mb749
  namespace: my-namespace
data:
  FOO: BAR

Working with Names

A prefix or suffix can be set for all Resources in a project with the namePrefix and nameSuffix fields. This sets a name prefix and suffix for both generated Resources (e.g. ConfigMaps and Secrets) and non-generated Resources.

Resources such as Deployments and StatefulSets may reference other Resources such as ConfigMaps and Secrets in the Pod Spec. The name prefix and suffix will also propagate to Resource references in a project. Typical uses cases include Service reference from a StatefulSet, ConfigMap reference from a Pod Spec, and Secret reference from a Pod Spec.

Add Name Prefix

namePrefix can be used to add a prefix to the name of all Resources in a project.

Here is an example of how to add a prefix to a Deployment.

  1. Create a Kustomization file.
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namePrefix: foo-

resources:
- deploy.yaml
  1. Create a Deployment manifest.
# deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: example
  1. Add name prefix with kustomize build.
kustomize build .

The output shows that the namePrefix field is used to add a prefix to the name of the Deployment.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: foo-example

Add Name Suffix

nameSuffix can be used to add a suffix to the name of all Resources in a project.

Here is an example of how to add a suffix to the name of a Deployment and a generated ConfigMap. The ConfigMap is generated with configMapGenerator.

  1. Create a Kustomization file.
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
nameSuffix: -bar

configMapGenerator:
- name: my-config
  literals:
  - FOO=BAR

resources:
- deploy.yaml
  1. Create a Deployment manifest.
# deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: example
  1. Add name suffix with kustomize build.
kustomize build .

The output shows that the nameSuffix field is used to add a suffix to the name of the Deployment and the generated ConfigMap.

kind: ConfigMap
apiVersion: v1
metadata:
  name: my-config-bar-m2mg5mb749
data:
  FOO: BAR
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: example-bar

Propagate Name Prefix to Resource Reference

namePrefix and nameSuffix propagate Resources name changes to Resource references in a project.

Here is an example of how the name prefix of a generated ConfigMap is propagated to the Pod Spec of a Deployment that references the ConfigMap to set a container environment variable.

  1. Create a Kustomization file.
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namePrefix: foo-

configMapGenerator:
- name: special-config
  literals:
  - special.how=very

resources:
- deploy.yaml
  1. Create a Deployment manifest. This Deployment is configured to set an environment variable in the busybox container using data from the generated ConfigMap.
# deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: example
  name: example
spec:
  replicas: 1
  selector:
    matchLabels:
      app: example
  template:
    metadata:
      labels:
        app: example
    spec:
      containers:
      - image: registry.k8s.io/busybox
        name: busybox
        command: [ "/bin/sh", "-c", "env" ]
        env:
          - name: SPECIAL_LEVEL_KEY
            valueFrom:
              configMapKeyRef:
                name: special-config
                key: special.how
  1. Add name prefix with kustomize build.
kustomize build .

The output shows that the name prefix is propagated to the ConfigMap name reference in the Deployment Pod Spec.

kind: ConfigMap
apiVersion: v1
metadata:
  name: foo-special-config-9k6fhm8659
data:
  special.how: very
---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: example
  name: foo-example
spec:
  replicas: 1
  selector:
    matchLabels:
      app: example
  template:
    metadata:
      labels:
        app: example
    spec:
      containers:
      - command:
        - /bin/sh
        - -c
        - env
        env:
        - name: SPECIAL_LEVEL_KEY
          valueFrom:
            configMapKeyRef:
              key: special.how
              name: foo-special-config-9k6fhm8659
        image: registry.k8s.io/busybox
        name: busybox

Last modified November 25, 2023: Add common Tasks to documentation (#5383) (bfb00ecb)