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Learning the example analysis of helmchart in K8s series on mac, I believe that many inexperienced people don't know what to do about it. Therefore, this article summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

Similar to php's composer, go's go vendor, linux's yum, helm are management tools for K8s application deployment.

How to use it on mac?

Brew install helm

It should be noted that helm2 has changed a lot compared with hlm3.

There is a layer of proxy tiller between helm2 and K8s, but RBAC is enabled by default since kubernetes 1.6. This is an important feature of Kubernetes security / enterprise availability. But when RBAC is turned on, it becomes very complex to manage and configure Tiller. In order to simplify the trial cost of helm, we give a default configuration that does not need to care about security rules. However, this can cause some users to accidentally gain permissions that they do not need. Also, the administrator / SRE needs to learn a lot of additional knowledge to deploy Tiller to a multi-tenant K8S cluster in a security-focused production environment and make it work.

After understanding the common usage scenarios of community members, we found that Tiller's release management system does not need to rely on Operator in the cluster to maintain state or act as a central hub for Helm publishing information. Instead, we can simply get the information from the Kubernetes API server, render the Charts client, and store the installation record in Kubernetes.

Helm2 requires tiller to be installed

Helm init-client-only-stable-repo-url https://aliacs-app-catalog.oss-cn-hangzhou.aliyuncs.com/charts/

Helm3 has removed the init command

The package managed by helm, called chart, creates a chart

% helm create mychart Creating mychart

Take a look at what is in chart?

% cd mychart% tree. | _ Chart.yaml | _ charts | _ templates | | _ deployment.yaml | | _ NOTES.txt | | _ ingress.yaml | | _ tests | | | _ test-connection.yaml | | _ service.yaml | | _ hpa.yaml | | _ serviceaccount.yaml | | _ helpers.tpl | _ values.yaml

The values filled in the YAML file template (go template syntax) under the Templates directory are defined in values.yaml by default, such as the container image defined in deployment.yaml:

% cat mychart/values.yaml | grep repository repository: nginx

The above variable values are the default values automatically generated during create chart, and you can modify them according to the actual situation.

Write an introduction to the application

Mychart/Chart.yaml

Write application specific deployment information

Edit mychart/values.yaml, which will deploy a Nginx in Kubernetes by default. The following is the contents of the values.yaml file for the mychart application

# check whether dependencies and templates are configured correctly

% helm lint mychart== > Linting mychart [ERROR] Chart.yaml: unable to parse YAML error converting YAML to JSON: yaml: line 27: could not find expected':'[ERROR] templates/: cannot load Chart.yaml: error converting YAML to JSON: yaml: line 27: could not find expected':'[ERROR]: unable to load chart cannot load Chart.yaml: error converting YAML to JSON: yaml: line 27: could not find expected':'

Error: 1 chart (s) linted, 1 chart (s) failed

% helm lint mychart== > Linting mychart [INFO] Chart.yaml: icon is recommended

1 chart (s) linted, 0 chart (s) failed

Packaged application

% helm package mychart / / package the application Successfully packaged chart and saved it to: / Users/xiazemin/go/src/github.com/xiazemin/helm_learn/mychart-0.1.0.tgz

The mychart directory will be packaged into a mychart-0.1.0.tgz format zip file, which will be placed in the current directory.

If you want to see more detailed output, you can add the-- debug parameter to view the packaged output.

Offline deployment

Note: if ~ / .kube / config does not exist, use helm-- kubeconfig to specify the configuration file.

# method 1$ helm install demo-test. / mychart

# you can install according to different configurations. The default is values.yaml# helm install demo-test. / mychart-f. / mychart/values-prod.yaml

# method II $helm install demo-test. / mychart-0.1.0.tgz

$helm list

# upgrade # $helm upgrade demo-test. / mychart-0.2.0.tgzhelm install demo-test. / mychartNAME: demo-testLAST DEPLOYED: Sun Apr 4 16:53:14 2021NAMESPACE: defaultSTATUS: deployedREVISION: 1NOTES:1. Get the application URL by running these commands: export POD_NAME=$ (kubectl get pods-- namespace default-l "app.kubernetes.io/name=mychart App.kubernetes.io/instance=demo-test "- o jsonpath=" {.items [0] .metadata.name} ") export CONTAINER_PORT=$ (kubectl get pod-- namespace default $POD_NAME-o jsonpath=" {.spec.containers [0] .ports [0] .contain erPort} ") echo" Visit items to use your application "kubectl-namespace default port-forward $POD_NAME 8080 to use your application Port% helm listNAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSIONdemo-test default 1 2021-04-04 16 purl 53 14.890414 + 0800 CST deployed mychart-0.1.0 1.16.0

Publish the application to Repository

Harbor1.6+ supports storage of helm charts, where helm is used to install harbor

In order to simplify the test operation here, I turned off the mount of the data volume and used NodePort to access it.

After reading the above, have you mastered the method of learning the sample analysis of helmchart in the K8s series on mac? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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