Shell-operator is a tool for running event-driven scripts in a Kubernetes cluster.

This operator is not an operator for a particular software product such as prometheus-operator or kafka-operator. Shell-operator provides an integration layer between Kubernetes cluster events and shell scripts by treating scripts as hooks triggered by events. Think of it as an operator-sdk but for scripts.

Shell-operator is used as a base for more advanced addon-operator that supports Helm charts and value storages.

Shell-operator provides:

• Ease of management of a Kubernetes cluster: use the tools that Ops are familiar with. It can be bash, python, kubectl, etc.
• Kubernetes object events: hook can be triggered by add, update or delete events. Learn more about hooks.
• Object selector and properties filter: shell-operator can monitor a particular set of objects and detect changes in their properties.
• Simple configuration: hook binding definition is a JSON or YAML document on script's stdout.
• Validating webhook machinery: hook can handle validating for Kubernetes resources.
• Conversion webhook machinery: hook can handle version conversion for Kubernetes resources.

Documentation

Please see the docs for more in-depth information and supported features.

Examples and notable users

More examples of how you can use shell-operator are available in the examples directory.

Prominent shell-operator use cases include:

• Deckhouse Kubernetes platform where both projects, shell-operator and addon-operator, are used as the core technology to configure & extend K8s features;
• KubeSphere Kubernetes platform's installer;
• Kafka DevOps solution from Confluent.

Please find out & share more examples in Show & tell discussions.

Articles & talks

Shell-operator has been presented during KubeCon + CloudNativeCon Europe 2020 Virtual (Aug'20). Here is the talk called "Go? Bash! Meet the shell-operator":

• YouTube video;
• text summary;
• slides.

Official publications on shell-operator:

• "shell-operator v1.0.0: the long-awaited release of our tool to create Kubernetes operators" (Apr'21);
• "shell-operator & addon-operator news: hooks as admission webhooks, Helm 3, OpenAPI, Go hooks, and more!" (Feb'21);
• "Kubernetes operators made easy with shell-operator: project status & news" (Jul'20);
• "Announcing shell-operator to simplify creating of Kubernetes operators" (May'19).

Other languages:

• Chinese: "介绍一个不太小的工具：Shell Operator"; "使用shell-operator实现Operator";
• Dutch: "Een operator om te automatiseren – Hoe pak je dat aan?";
• Russian: "shell-operator v1.0.0: долгожданный релиз нашего проекта для Kubernetes-операторов"; "Представляем shell-operator: создавать операторы для Kubernetes стало ещё проще".

Community

Please feel free to reach developers/maintainers and users via GitHub Discussions for any questions regarding shell-operator.

You're also welcome to follow @flant_com to stay informed about all our Open Source initiatives.

License

Apache License 2.0, see LICENSE.