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| # Helm Operator (Flux) vs Helm | ||
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| In this document you can read about findings about [helm 3](https://helm.sh/docs/) pros and cons in comparision with the [helm operator](https://docs.fluxcd.io/projects/helm-operator/en/latest/). | ||
| In this document you can read about findings about the [Helm 3](https://helm.sh/docs/) in comparision with the [Helm operator](https://docs.fluxcd.io/projects/helm-operator/en/latest/). | ||
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| ## Helm 3 features | ||
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| The Helm 3 has numerous new features, but a few deserve highlighting here: | ||
| The new version of Helm has numerous new features, but a few deserve highlighting here: | ||
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| - Releases are stored in a new format | ||
| - Releases are stored in a new format (in secrets, not like before in the config maps) | ||
| - There is no in-cluster (Tiller) component | ||
| - Helm 3 includes support for a new version of Helm charts (Charts v2) | ||
| - Helm 3 also supports library charts -- charts that are used primarily as a resource for other charts. | ||
| - Experimental support for storing Helm charts in OCI registries (e.g. Docker Distribution) is available for testing. | ||
| - A 3-way strategic merge patch is now applied when upgrading Kubernetes resources. | ||
| - New version of [Helm charts](https://helm.sh/docs/topics/charts/) | ||
| - [Library charts](https://helm.sh/docs/topics/library_charts/) - charts that are used primarily as a resource for other charts | ||
| - Experimental support for storing Helm charts in OCI registries is available for testing | ||
| - A 3-way strategic merge patch is now applied when upgrading Kubernetes resources | ||
| - A chart's supplied values can now be validated against a JSON schema | ||
| - A number of small improvements have been made to make Helm more secure, usable, and robust. | ||
| - A number of small improvements have been made to make Helm more secure, usable, and robust | ||
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| ## Helm Operator features | ||
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| The Helm operator is a [Flux](https://github.com/fluxcd/flux) extension which automates Helm Charts in a GitOps manner. | ||
| The Helm operator is a [FluxCD](https://github.com/fluxcd/flux) extension which automates Helm Charts in a GitOps manner. | ||
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| See the features it provides: | ||
| - Declarative helm install/upgrade/delete of charts | ||
| - Pulls charts from public or private Helm repositories over HTTPS | ||
| - Pulls charts from public or private Git repositories over SSH | ||
| - Chart release values can be specified inline in the HelmRelease object or via secrets, configmaps or URLs | ||
| - Automated chart upgrades based on container image tag policies (requires Flux) | ||
| - Automatic purging on chart install failures | ||
| - Automatic rollback on chart upgrade failures | ||
| - Declarative install, upgrade, and delete of HelmRelease CR | ||
| - Pulls chart from any chart source: | ||
| - Public or private Helm repositories over HTTP/S | ||
| - Public or private Git repositories over HTTPS or SSH | ||
| - Any other public or private chart source using one of the available Helm downloader plugins | ||
| - Allows Helm values to be specified: | ||
| - In-line in the HelmRelease resource | ||
| - In (external) sources, e.g. ConfigMap and Secret resources, or a (local) URL | ||
| - Automated purging on release install failures | ||
| - Automated (optional) rollback on upgrade failures | ||
| - Automated image upgrades (Flux) | ||
| - Automated (configurable) chart dependency updates for Helm charts from Git sources on install or upgrade (Flux) | ||
| - Detection and recovery from Helm storage mutations (e.g. a manual Helm release that was made but conflicts with the declared configuration for the release) | ||
| - Parallel and scalable processing of different HelmRelease resources using workers | ||
| - Supports both Helm 2 and 3 | ||
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| ## Pros and cons | ||
| ## Implementation | ||
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| The Helm Operator beyond the Helm features like managing the charts provides also a lot of features for the Github. | ||
| Read below sections for more about implementation details in Helm Broker. | ||
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| With actual implementation of the Helm Broker, implementing the Helm Operator or Helm 3 should be similar. | ||
| ### Helm 3 | ||
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| In Helm Broker we use go-getter library which help us to store AddOns in the Github repositories, that approach can be improved easily with the Helm Operator features. | ||
| The Helm 3 provides a support for `v2` charts, so it shouldn't be a problem to implement it in the Helm Broker. Even without adjusting the AddOns itself. | ||
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| If possible we should migrate to Helm Operator when the first use-case for it will show up. | ||
| To download the Helm 3 binary, use the following command: | ||
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| ## For future | ||
| ``` | ||
| curl https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3 | bash | ||
| ``` | ||
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| We should remember about features that Helm Operator provides, and track the issues which are blocking us from migration to it. | ||
| ### Helm Operator | ||
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| The Helm Operator will support Helm 3 after implementing this [issue](https://github.com/fluxcd/helm-operator/issues/8) | ||
| In order to use Helm Operator approach, we may need to provide the following dependencies to your cluster: | ||
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| - [Helm Operator](https://github.com/fluxcd/helm-operator/tree/v1.1.0/chart/helm-operator) | ||
| - [HelmRelease CR](https://raw.githubusercontent.com/fluxcd/helm-operator/1.1.0/deploy/crds.yaml) | ||
| - **Optional** [FluxCD](https://github.com/fluxcd/helm-operator/tree/master/chart/helm-operator) | ||
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| >**NOTE:** When working with FluxCD use [FluxCTL](https://github.com/fluxcd/flux/releases/tag/1.19.0). | ||
| With this solution the Helm Broker would need to create a HelmRelease CR in the provisioning process. It wouldn't need the Helm client anymore. | ||
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| The Helm Operator beyond the Helm features like managing the charts provides also a lot of features for the Github, but most of them can be used only when FluxCD is configured and installed on the cluster. | ||
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| ### Migration | ||
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| The Helm 3 provides a migration [CLI](https://github.com/helm/helm-2to3) along with the [documentation](https://helm.sh/docs/topics/v2_v3_migration/). | ||
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| ## Links | ||
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| Explore the following links to expand your knowledge about above things: | ||
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| - [Example app deploy with Helm 3](https://www.civo.com/learn/guide-to-helm-3-with-an-express-js-microservice) | ||
| - [Example app automation with Helm Operator and Flux](https://www.civo.com/learn/gitops-using-helm3-and-flux-for-an-node-js-and-express-js-microservice) | ||
| - [Explanation of the Helm 3 features](https://thenewstack.io/helm-3-is-almost-boring-and-thats-a-great-sign-of-maturity/) |