72 lines
2.5 KiB
Markdown
72 lines
2.5 KiB
Markdown
# Django Helm Chart
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A generic Django (plus Celery) Helm chart.
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# Preparing your Django app
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This chart supports a web plus optional celery and beat deployments. Be prepared to extend it as necessary.
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Django settings will be managed by environment variables. `django-environ` works well for this and can parse the DATABASE_URL connection string. This chart expects SECRET_KEY and DATABASE_URL variables.
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Kubernetes works best when it is able to determine application health. You Django app should have a `/_health/` view such as
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```
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def health(request):
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return HttpResponse("ok", content_type="text/plain")
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urlpatterns = [
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path("_health/", health),
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...
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```
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Set the value web.livenessProbe.path and web.readinessProbe.path to change the URL.
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## Run commands
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This helm chart will set a "role" environment variable to web, worker, or beat. Your Docker image could read this variable and run the correct command.
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Alternatively, set the service.command. For example:
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```
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web:
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command:
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- run_it
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```
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# Usage
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1. Add our Helm chart repo `helm repo add django https://burke-software.gitlab.io/django-helm-chart/`
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2. Review our values.yaml. At a minimum you'll need to set env.secret.SECRET_KEY and env.secret.DATABASE_URL.
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3. Install the chart `helm install your-app django/django -f your-values.yml`
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# Tips
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- Do you really need kubernetes? It's very complex.
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- Don't use helm without [helm diff](https://github.com/databus23/helm-diff). One typo will wipe your app without warning otherwise.
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- While supported, I don't suggest running stateful services like PostgreSQL in kubernetes. Upgrades will likely involve downtime or extensive and arcane knowledge.
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- It's fine to use this chart as a reference for your own chart instead of directly using it.
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## Managing environment variables and secrets
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I suggest either
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- Keep them in a values.yml file in a private repo
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- Make use of --reuse-values and --set
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- Keep them in a non helm chart managed service
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## Deploying in CI
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I use lwolf/helm-kubectl-docker with Gitlab CI. [Example](https://gitlab.com/glitchtip/glitchtip-frontend/-/blob/master/.gitlab-ci.yml).
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# Support development
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Maintaining this chart takes time. Considering supporting it by
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- [Donating on liberapay](https://liberapay.com/burke-software/)
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- Check out [GlitchTip](https://glitchtip.com) error tracking, which is where this project started
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Commercial support is available - email info@burkesoftware.com
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# Contributing
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Contributions are welcome. Report bugs on GitLab issues. Please only open feature requests that you'd like to implement yourself or pay for. |