README.md

KubeOps Generator

This is a C# source generator for KubeOps and operators. It is used to generate convenience functions to help registering resources within an operator.

Usage

The generator is automatically used when the KubeOps.Generator package is referenced.

dotnet add package KubeOps.Generator

which results in the following csproj reference:

<ItemGroup>
    <PackageReference Include="KubeOps.Generator" Version="..." />
</ItemGroup>

Generated Sources

The generator will automatically generate functions for the IOperatorBuilder.

Entity Metadata / Entity Definitions

The generator creates a file in the root namespace called EntityDefinitions.g.cs. This file contains all entities that are annotated with the KubernetesEntityAttribute. The static class contains the EntityMetadata for the entities as well as a function to register all entities within the IOperatorBuilder.

Example

using KubeOps.Abstractions.Builder;
using KubeOps.Abstractions.Entities;

public static class EntityDefinitions
{
    public static readonly EntityMetadata V1TestEntity = new("TestEntity", "v1", "testing.dev", null);
    public static IOperatorBuilder RegisterEntities(this IOperatorBuilder builder)
    {
        builder.AddEntity<global::Operator.Entities.V1TestEntity>(V1TestEntity);
        return builder;
    }
}

Entity Initializer

All entities must have their Kind and ApiVersion fields set. To achieve this, the generator creates an initializer file for each entity that is annotated with the KubernetesEntityAttribute.

For each partial class that does not contain a default constructor, the generator will create a default constructor that sets the Kind and ApiVersion fields.

For each non partial class, a method extension is created that sets the Kind and ApiVersion fields.

Note

Setting your class partial is crucial for the generator to create the constructor. Also, if some default constructor is already present, the generator uses the method extension fallback.

Example

namespace Operator.Entities;

[KubernetesEntity(Group = "testing.dev", ApiVersion = "v1", Kind = "TestEntity")]
public partial class V1TestEntity : CustomKubernetesEntity
{
}

The partial defined entity above will generate the following V1TestEntity.init.g.cs file:

namespace Operator.Entities;
public partial class V1TestEntity
{
    public V1TestEntity()
    {
        ApiVersion = "testing.dev/v1";
        Kind = "TestEntity";
    }
}

The non partial defined entity below:

namespace Operator.Entities;

[KubernetesEntity(Group = "testing.dev", ApiVersion = "v1", Kind = "TestEntity")]
public class V1TestEntity : CustomKubernetesEntity
{
}

will generate a static method extension in EntityInitializer.g.cs for the entity to initialize the fields:

public static class EntityInitializer
{
    public static global::Operator.Entities.V1ClusterTestEntity Initialize(this global::Operator.Entities.V1ClusterTestEntity entity)
    {
        entity.ApiVersion = "testing.dev/v1";
        entity.Kind = "ClusterTestEntity";
        return entity;
    }
}

Controller Registrations

The generator creates a file in the root namespace called ControllerRegistrations.g.cs. This file contains a function to register all found controllers (i.e. classes that implement the IEntityController<T> interface).

Example

using KubeOps.Abstractions.Builder;

public static class ControllerRegistrations
{
    public static IOperatorBuilder RegisterControllers(this IOperatorBuilder builder)
    {
        builder.AddController<global::Operator.Controller.V1TestEntityController, global::Operator.Entities.V1TestEntity>();
        return builder;
    }
}

Finalizer Registrations

The generator creates a file in the root namespace called FinalizerRegistrations.g.cs. This file contains all finalizers with generated finalizer-identifiers. Further, a function to register all finalizers is generated.

Example

using KubeOps.Abstractions.Builder;

public static class FinalizerRegistrations
{
    public const string FinalizerOneIdentifier = "testing.dev/finalizeronefinalizer";
    public const string FinalizerTwoIdentifier = "testing.dev/finalizertwofinalizer";
    public static IOperatorBuilder RegisterFinalizers(this IOperatorBuilder builder)
    {
        builder.AddFinalizer<global::Operator.Finalizer.FinalizerOne, global::Operator.Entities.V1TestEntity>(FinalizerOneIdentifier);
        builder.AddFinalizer<global::Operator.Finalizer.FinalizerTwo, global::Operator.Entities.V1TestEntity>(FinalizerTwoIdentifier);
        return builder;
    }
}

General Operator Extensions

The generator creates a file in the root namespace called OperatorExtensions.g.cs. It contains convenience functions to register all generated sources.

Example

using KubeOps.Abstractions.Builder;

public static class OperatorBuilderExtensions
{
    public static IOperatorBuilder RegisterComponents(this IOperatorBuilder builder)
    {
        builder.RegisterEntities();
        builder.RegisterControllers();
        builder.RegisterFinalizers();
        return builder;
    }
}