[Helm Chart] Learning Helm on Kubernetes in 60 minutes!!

Contents

Anh em cần coi clip của anh này là master helm liền.

https://www.youtube.com/watch?v=LWW8_S0dbG8

Không hiểu sao nó không hiện video. Rất hay các bạn tự click nhé.

Intall helm cli on linux

install helm trên ubuntu:

curl https://baltocdn.com/helm/signing.asc | sudo apt-key add -
sudo apt-get install apt-transport-https --yes
echo "deb https://baltocdn.com/helm/stable/debian/ all main" | sudo tee /etc/apt/sources.list.d/helm-stable-debian.list
sudo apt-get update
sudo apt-get install helm

Install helm cli on windows

https://www.youtube.com/watch?v=L3iNhrjQILM

Access this link: https://github.com/helm/helm/releases/

thế là ok.

Tạo ra 1 chart mẫu

helm create fullname-override

Câu lệnh ví dụ:

helm template generic/ --values /root/value_helm_tiki.yaml

gen ra 1 package helm

helm package ./tikici-helm-charts/common -d tikici-helm-charts/generic/charts/

Đánh index để public helm chart trên github

helm repo index ./

Các xuất file value.yaml của helm-chart

helm repo add rancher-latest https://releases.rancher.com/server-charts/latest
-->"rancher-latest" has been added to your repositories

helm search repo rancher-latest
>>output
NAME                  	CHART VERSION	APP VERSION	DESCRIPTION                                       
rancher-latest/rancher	2.6.0        	v2.6.0     	Install Rancher Server to manage Kuberne

helm show values rancher-latest/rancher > rancher.yaml
>>Lúc này chúng ta thấy file value được xuất ra
root@work-space-u20:~/mylab-helm-chart/value-helm# ls
rancher.yaml

Nếu bạn gõ:
helm install cron-test ./ --values ./value_helm.yaml

mà gặp lỗi này: Error: cannot re-use a name that is still in use

helm ls -n <namespaces> helm delete -n my-namespace my-release

Cách để print helm chart ra từng file.

helm search repo spinnaker
helm pull opsmx/spinnaker --untar
mkdir rendering

helm template --dry-run spinnaker <folder_helm-chart> | awk -vout=<folder_manifest-yaml> -F": " '$0~/^# Source: /{file=out"/"$2; print "Creating "file; system ("mkdir -p $(dirname "file"); echo -n "" > "file)} $0!~/^#/ && $0!="---"{print $0 >> file}'

example:
helm template --dry-run spinnaker ./spinnaker | awk -vout=./rendering -F": " '$0~/^# Source: /{file=out"/"$2; print "Creating "file; system ("mkdir -p $(dirname "file"); echo -n "" > "file)} $0!~/^#/ && $0!="---"{print $0 >> file}'

https://github.com/helm/helm/issues/4680#issuecomment-613201032

get manifest/value of helm that is installed on k8s

PS C:\Users\thang.tran> helm.exe list -A
NAME                            NAMESPACE       REVISION        UPDATED                                 STATUS          CHART                                   APP VERSION
aws-load-balancer-controller    kube-system     1               2022-06-02 12:42:38.33274549 +0000 UTC  deployed        aws-load-balancer-controller-1.3.2      v2.3.0

PS C:\Users\thang.tran> helm -n kube-system get values aws-load-balancer-controller
USER-SUPPLIED VALUES:
clusterName: mdc-platf-dev-fed
image:
  tag: v2.3.0
serviceAccount:
  create: false
  name: aws-load-balancer-controller

>>> In order to get manifest(deploy, service, ingress,...)
helm get manifest aws-load-balancer-controller -n kube-system

Use Golang language in Helm chart

mình sử dụng printf trong helm chart
cài này nó hao hao giống code golang còn trong helm chart nó gọi là:
https://helm.sh/docs/chart_template_guide/function_list/

image: "{{ .Values.linux.image.repository }}:{{ .Values.linux.image.tag | default (printf "prod-linux-%s" .Chart.AppVersion) }}"