Instalamos helm desde https://github.com/helm/helm/releases/
Inicialmente aparece el repositorio
kubernetes-charts.storage.googleapis.com, que como se nos advierte,
está obsoleto:
helm repo list
WARNING: "kubernetes-charts.storage.googleapis.com" is deprecated for "stable" and will be deleted Nov. 13, 2020.
WARNING: You should switch to "https://charts.helm.sh/stable" via:
WARNING: helm repo add "stable" "https://charts.helm.sh/stable" --force-update
NAME URL
stable https://kubernetes-charts.storage.googleapis.com
Así, que actualizmos a https://charts.helm.sh/stable, tal como se
recomienda:
helm repo add "stable" "https://charts.helm.sh/stable" --force-update
Y ahora el repositorio stable corresponde a charts.helm.sh/stable:
helm repo list
NAME URL
stable https://charts.helm.sh/stable
Buscamos una aplicación en el hub de helm, por ejemplo redis:
helm search hub redis
URL CHART VERSION APP VERSION DESCRIPTION
https://hub.helm.sh/charts/drycc-canary/redis 1.0.0 A Redis database for use inside a Kubernetes cl...
https://hub.helm.sh/charts/groundhog2k/redis 0.1.2 6.0.9 A Helm chart for Redis on Kubernetes
https://hub.helm.sh/charts/wener/redis 12.1.1 6.0.9 Open source, advanced key-value store. It is of...
https://hub.helm.sh/charts/hephy/redis 2.4.2 A Redis database for use inside a Kubernetes cl...
https://hub.helm.sh/charts/drycc/redis 1.1.0 A Redis database for use inside a Kubernetes cl...
https://hub.helm.sh/charts/bitnami/redis 12.1.1 6.0.9 Open source, advanced key-value store. It is of...
https://hub.helm.sh/charts/choerodon/redis 0.2.5 0.2.5 redis for Choerodon
https://hub.helm.sh/charts/inspur/redis-cluster 0.0.2 5.0.6 Highly available Kubernetes implementation of R...
https://hub.helm.sh/charts/hkube/redis-ha 3.6.1005 5.0.5 Highly available Kubernetes implementation of R...
https://hub.helm.sh/charts/dandydeveloper/redis-ha 4.10.5 6.0.7 Highly available Kubernetes implementation of R...
https://hub.helm.sh/charts/softonic/redis-sharded 0.3.0 6.0.6 A Helm chart for sharded redis
https://hub.helm.sh/charts/bitnami/redis-cluster 4.0.1 6.0.9 Open source, advanced key-value store. It is of...
https://hub.helm.sh/charts/kfirfer/redis-commander 0.0.2 latest A Helm chart for redis-commander
https://hub.helm.sh/charts/prometheus-community... 3.7.0 1.11.1 Prometheus exporter for Redis metrics
https://hub.helm.sh/charts/hmdmph/redis-pod-lab... 1.0.2 1.0.0 Labelling redis pods as master/slave periodical...
https://hub.helm.sh/charts/wyrihaximusnet/redis... 1.0.2 v1.0.1 Redis Database Assignment Operator
https://hub.helm.sh/charts/enapter/keydb 0.16.2 6.0.16 A Helm chart for KeyDB multimaster setup
https://hub.helm.sh/charts/pozetron/keydb 0.5.1 v5.3.3 A Helm chart for multimaster KeyDB optionally w...
Se puede obtener información sobre un chart concreto con:
helm show all bitnami/redis-cluster
annotations:
category: Database
apiVersion: v2
appVersion: 6.0.9
dependencies:
- name: common
repository: https://charts.bitnami.com/bitnami
tags:
- bitnami-common
version: 1.x.x
description: Open source, advanced key-value store. It is often referred to as a data
structure server since keys can contain strings, hashes, lists, sets and sorted
sets.
home: https://github.com/bitnami/charts/tree/master/bitnami/redis-cluster
icon: https://bitnami.com/assets/stacks/redis/img/redis-stack-220x234.png
keywords:
- redis
- keyvalue
- database
maintainers:
- email: containers@bitnami.com
name: Bitnami
name: redis-cluster
sources:
- https://github.com/bitnami/bitnami-docker-redis
- http://redis.io/
version: 4.0.1
---
## Global Docker image parameters
## Please, note that this will override the image parameters, including dependencies, configured to use the global value
## Current available global Docker image parameters: imageRegistry and imagePullSecrets
##
global:
# imageRegistry: myRegistryName
# imagePullSecrets:
# - myRegistryKeySecretName
# storageClass: myStorageClass
redis: {}
## Bitnami Redis image version
## ref: https://hub.docker.com/r/bitnami/redis/tags/
##
image:
registry: docker.io
repository: bitnami/redis-cluster
## Bitnami Redis image tag
## ref: https://github.com/bitnami/bitnami-docker-redis#supported-tags-and-respective-dockerfile-links
##
tag: 6.0.9-debian-10-r13
## Specify a imagePullPolicy
## Defaults to 'Always' if image tag is 'latest', else set to 'IfNotPresent'
## ref: http://kubernetes.io/docs/user-guide/images/#pre-pulling-images
Alternativamente podemos hacer la búsqueda en la web https://artifacthub.io/:
https://artifacthub.io/packages/search?page=1&ts_query_web=redis&kind=0
En la que podemos seleccionar la opción que queremos y nos da detalles sobre el chart y los parámetros que podemos utilizar en la instalación.
helm repo add bitnami https://charts.bitnami.com/bitnami
helm install my-redis bitnami/redis-cluster
Probamos que accedemos a la aplicación siguiendo las instrucciones y una vez que queramos eliminarla, lo hacemos con:
helm delete my-redis
Un chart tiene una estructura básica que podemos obtener con:
helm create chart
Creating chart1
cd chart1/ && ls
charts Chart.yaml templates values.yaml
La estructura principal del Chart se define en Chart.yaml, los
objetos de k8s se definen en el directorio templates y los valores
que queremos asignar a dichos objetos en values.yml
Vamos a probar la utilización de un chart muy sencillo que permite hacer un despliegue de nginx con el número de réplicas que se defina, utilizar un servicio de tipo ClusterIP o NodePort a elección del usuario y opcionalmente definir el nombre del servicio para accder a través de ingress.
Editamos el fichero mynginx/values.yaml y ajustamos el valor del
host a la dirección de nuestro cluster de minikube. Luego creamos una
instancia del chart:
helm install prueba mynginx/
Y comprobamos que se puede acceder al despliegue.