KubeOps - Kubernetes Operators in .NET

Build Kubernetes Operators in .NET with Ease

KubeOps is a Kubernetes Operator SDK designed for .NET developers. It allows you to leverage your C# skills and the rich .NET ecosystem to build powerful Kubernetes controllers that automate the management of complex applications. KubeOps simplifies operator development by providing high-level abstractions, code generators, and helper utilities.

For comprehensive documentation, tutorials, and API references, please visit the official KubeOps Documentation Site.

The documentation is also provided within the code itself (description of methods and classes), and each package contains a README with further information.

Key Features

• Define CRDs in C#: Model your Custom Resource Definitions (CRDs) using plain C# classes and attributes.
• Controller Logic: Implement reconciliation logic using the IEntityController<TEntity> interface.
• Finalizers: Easily add cleanup logic before resource deletion with IEntityFinalizer<TEntity>.
• Webhooks: Create Admission (validating/mutating) and Conversion webhooks integrated with ASP.NET Core.
• Code Generation: Includes Roslyn source generators and a CLI tool (dotnet kubeops) to automate boilerplate code for CRDs, controllers, and RBAC rules.
• Enhanced Kubernetes Client: Provides convenience methods built on top of the official client library.
• Leader Election: Automatic handling for high-availability operator deployments.

Getting Started

There are two ways to start building an operator with KubeOps:

1. Using the normal dotnet console template:

   # Create a new console project
   dotnet new console -n MyOperator
   cd MyOperator
   
   # Add the KubeOps.Operator package
   dotnet add package KubeOps.Operator

2. Using the project templates:

   # Install the templates
   dotnet new install KubeOps.Templates
   
   # Create a new operator project
   dotnet new operator -n MyOperator
   cd MyOperator

Both methods generate a basic operator structure with a sample custom resource, controller, and finalizer. The template approach is simpler and more direct, while the CLI provides additional commands for generating CRDs, RBAC rules, and more.

For detailed tutorials and guides, visit the KubeOps Documentation Site.

Packages

All packages target .NET 8.0 and .NET 9.0, leveraging modern C# features. The underlying Kubernetes client library (KubernetesClient.Official) also follows this versioning strategy.

The SDK is designed to be modular. You can include only the packages you need:

Package	Description
KubeOps.Abstractions	Defines core interfaces, attributes (like [KubernetesEntity]), and base classes used across the SDK. Essential for defining your custom resources and controllers.
KubeOps.Cli	A .NET Tool providing commands for scaffolding projects, generating Custom Resource Definitions (CRDs), and more.
KubeOps.Generator	Contains Roslyn Source Generators to automate boilerplate code generation for CRDs and controllers based on your definitions.
KubeOps.KubernetesClient	Provides an enhanced client for interacting with the Kubernetes API, built on top of the official KubernetesClient library. Offers convenience methods for common operator tasks.
KubeOps.Operator	The main engine of the SDK. Handles reconciling resources, watching for changes, and managing the operator lifecycle. This is the primary package needed to run an operator.
KubeOps.Operator.Web	Integrates the operator with ASP.NET Core to expose endpoints for features like Admission Webhooks.
KubeOps.Transpiler	Utilities for converting .NET type definitions into Kubernetes YAML manifests, specifically for CRDs and RBAC rules.
KubeOps.Templates	Project templates for creating new operator projects. Provides a quick start with pre-configured project structure and sample resources.

Examples

You can find various example operators demonstrating different features in the examples/ directory of this repository.

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details. This license applies to all packages in the KubeOps SDK.

Governance

KubeOps is maintained by the repository collaborators and maintainers. We welcome community contributions and aim to foster an open and collaborative development process. Decision-making primarily occurs through GitHub issues and pull requests.

Contribution

If you want to contribute, feel free to open a pull request or write issues :-) Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.

Read more about contribution (especially for setting up your local environment) in the CONTRIBUTING file.

In short:

• Check out the code
• Develop on KubeOps
• Use some Kubernetes to run the test operator against
• Create tests
• Build the whole solution (lint warnings will result in an error)
• Open PR

Motivation

KubeOps aims to provide a first-class experience for developing Kubernetes operators within the .NET ecosystem, offering an alternative to Go-based SDKs like Kubebuilder and Operator SDK, while embracing familiar C# patterns and tooling.

Why choose KubeOps?

• Leverage your .NET Skills: Build operators using C#, a language you already know, with access to the extensive .NET Base Class Library and NuGet ecosystem.
• Strong Typing & IDE Support: Benefit from compile-time checks and rich IDE features like IntelliSense and debugging.
• Simplified Abstractions: Focus on your reconciliation logic, not Kubernetes API boilerplate.
• Code Generation: Reduce manual effort with generators for CRDs, RBAC, and controller/webhook registrations.