Helm Charts

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Getting started ​

Install ​

Add the Helm repository:

shell
helm repo add hosst https://hosstio.github.io/helm-charts
helm repo update

Install with default values:

shell
helm install my-app hosst/standard

Minimal values ​

A minimal values.yaml for a web application:

yaml
nameOverride: my-app

image:
  registry: registry.example.com/
  name: my-app
  tag: "1.0.0"

service:
  ports:
    http:
      port: 80

deployment:
  containers:
    app:
      ports:
        http:
          containerPort: 8080

Install:

shell
helm install my-app hosst/standard -f values.yaml

Install from a source checkout ​

To install from a local clone of the chart instead of the packaged repository (handy when developing the chart, or when reproducing the exact command a CI pipeline runs), point helm at the chart directory:

shell
git clone https://gitlab.com/hosstio/helm-charts
helm install my-app helm-charts/charts/standard -f values.yaml

Values files layer left to right, so shared and environment-specific values can live in separate files:

shell
helm install my-app helm-charts/charts/standard \
  --values values.yaml \
  --values staging.yaml

Preview what an upgrade would change before applying it with the helm-diff plugin (helm plugin install https://github.com/databus23/helm-diff):

shell
helm diff upgrade my-app helm-charts/charts/standard \
  --values values.yaml \
  --values staging.yaml

Render the manifests without a cluster to catch a bad-values or template error:

shell
helm template my-app helm-charts/charts/standard \
  --values values.yaml \
  --values staging.yaml

Post-install notes ​

After helm install (or helm upgrade), the chart prints a summary of the release: the app/chart metadata, any ingress URLs, jobs and cronjobs, plus a handful of useful commands. A release with two ingresses (one without TLS), a job, a cronjob, two variables, a secret, and a mounted file renders like this:

text
📦 Chart "standard"
═══════════════════
A generic application Helm chart for Kubernetes

Status:     installed
App:        my-app
Version:    latest
Chart:      standard-0.1.0
Release:    my-app
Namespace:  default

 ⚠ WARNING: no TLS configured; connections are unencrypted.

🌐 Access
─────────

Open in your browser:

 • http://admin.example.com/dashboard
 • http://admin.example.com/metrics
 • https://app.example.com/
 • https://www.example.com/

📋 Jobs
───────

 • migrate (post-install)

⏰ Scheduled jobs
─────────────────

 • cleanup (@hourly)

🔧 Configuration
────────────────

Environment (ConfigMap `my-app-variables`):
 • DATABASE_HOST: db.internal
 • LOG_LEVEL: info

Secrets (Secret `my-app-secrets`):
 • DATABASE_PASSWORD: ********

Mounted files (ConfigMap `my-app-files`):
 • /etc/app/config.yaml

💻 Useful commands
──────────────────

Logs         $ kubectl logs -f deploy/my-app -n default
Logs (all)   $ kubectl logs -l app.kubernetes.io/instance=my-app -n default
Pods         $ kubectl get pods -l app.kubernetes.io/instance=my-app -n default
Shell        $ kubectl exec -it deploy/my-app -n default -- sh
Rollback     $ helm rollback my-app -n default
Values       $ helm get values my-app -n default

When no ingress is configured, the Access section instead shows a kubectl port-forward command, and the Jobs/Scheduled jobs sections only appear when jobs/cronJobs are set. The ⚠ WARNING line shows only when an ingress is served without TLS.

A Configuration section appears when variables, secrets, sealedSecrets, or any of the mounted*Files are set. It lists the ConfigMap, Secret, and SealedSecret each one produces. variables print their values, truncated at 60 characters; secrets and sealed secrets mask every value to a fixed ********, so nothing about the value (not even its length) is printed; the mounted-file blocks list paths only, since their values are whole file bodies. The values files themselves cannot be listed: helm merges the --values list before templates render and never exposes it to them.

App: is the app.kubernetes.io/name of the workload (driven by nameOverride/chartName), and Version: is the chart's appVersion, not the image tag.

Verify ​

shell
helm get manifest my-app
kubectl get all -l app.kubernetes.io/instance=my-app

Debug rendering ​

Preview what will be generated without deploying:

shell
helm template my-app hosst/standard -f values.yaml
helm template my-app hosst/standard -f values.yaml --set debug=true

Upgrade ​

shell
helm repo update
helm diff upgrade my-app hosst/standard -f values.yaml
helm upgrade my-app hosst/standard -f values.yaml