Skip to main content

· 5 min read

KCL is an open-source, constraint-based record and functional language that enhances the writing of complex configurations, including those for cloud-native scenarios. With its advanced programming language technology and practices, KCL is dedicated to promoting better modularity, scalability, and stability for configurations. It enables simpler logic writing and offers ease of automation APIs and integration with homegrown systems.

This section will update the KCL language community's latest developments every two weeks, including features, website updates, and the latest community news, helping everyone better understand the KCL community!

KCL Website: https://kcl-lang.io

Overview​

Thank you to all contributors for their outstanding work over the past two weeks (08.10-08.23 2023). Here is an overview of the key content:

🔧 Language and Toolchain Updates

  • KCL Import Tool Updates - Supports exporting JSON/YAML data to KCL configuration.
  • KCL IDE Updates - Supports right-click formatting ability, formatting individual files or parts of KCL code.
  • KCL Documentation Tool Updates - Exported documents support HTML escape.
  • KCL Package Management Tool KPM Updates - kpm run command execution and error message optimization, supports running KCL packages located in local paths.
  • KCL Language Updates - Optimized system package type check error messages and unified error message codes.

📰 Official Website and Use Case Updates

Special Thanks​

The following are listed in no particular order:

  • Thanks to @jakezhu9 for the contribution of converting JSON and YAML configuration data to KCL configuration in the KCL Import Tool 🙌 https://github.com/kcl-lang/kcl-go/pull/141
  • Thanks to @xxmao123 and @starkers for their contributions to the KCL NeoVim and Idea IDE extensions 🙌 https://github.com/kcl-lang/intellij-kcl/pull/12
  • Thanks to @kolloch, @prahaladramji, and others for their valuable feedback and discussions during the use of KCL in the past two weeks 🙌

Congratulations @jakezhu9 for becoming a KCL community Maintainer 🎉

KCL Operator​

KCL Operator provides cluster integration, allowing you to use Access Webhook to generate, mutate, or validate resources based on KCL configuration when apply resources to the cluster. Webhook will capture creation, application, and editing operations, and execute KCLRun on the configuration associated with each operation, and the KCL programming language can be used to

  • Add labels or annotations based on a condition.
  • Inject a sidecar container in all KRM resources that contain a PodTemplate.
  • Validating all KRM resources using KCL Schema, such as constraints on starting containers only in a root mode.
  • Generating KRM resources using an abstract model or combining and using different KRM APIs.

With KCL Operator, you can automate resource configuration management and security validation in a Kubernetes cluster using lightweight KCL code, without the need to develop a webhook server to dynamically mutate and validate configurations at runtime.

Furthermore, leveraging KCL's modeling and abstraction capabilities, we can define functionality abstractions/compositions for different resource APIs and expose them in the form of KCL Schema. We can further generate OpenAPI Schema definitions from KCL Schema for other clients in the cluster to use, without manually maintaining complex OpenAPI Schema definitions for API abstractions/compositions. Here is an example of using KCL Operator to modify resource annotations:

0. Prerequisites​

Prepare a Kubernetes cluster like k3d the kubectl tool.

1. Install KCL Operator​

kubectl apply -f https://raw.githubusercontent.com/kcl-lang/kcl-operator/main/config/all.yaml

Use the following command to observe and wait for the pod status to be Running.

kubectl get po

2. Deploy KCL Annotation Setting Model​

kubectl apply -f- << EOF
apiVersion: krm.kcl.dev/v1alpha1
kind: KCLRun
metadata:
  name: set-annotation
spec:
  # Set dynamic parameters required for the annotation modification model, here we can add the labels we want to modify/add
  params:
    annotations:
      managed-by: kcl-operator
  # Reference the annotation modification model on OCI
  source: oci://ghcr.io/kcl-lang/set-annotation
EOF

3. Deploy a Pod to Verify the Model Result​

Execute the following command to deploy a Pod resource:

kubectl apply -f- << EOF
apiVersion: v1
kind: Pod
metadata:
  name: nginx
  annotations:
    app: nginx
spec:
  containers:
  - name: nginx
    image: nginx:1.14.2
    ports:
    - containerPort: 80
EOF
kubectl get po nginx -o yaml | grep kcl-operator

We can see the following output:

    managed-by: kcl-operator

We can see that the Nginx Pod automatically added the annotation managed-by=kcl-operator.

In addition, besides referencing an existing model for the source field of the KCLRun resource, we can directly set KCL code for the source field to achieve the same effect. For example:

apiVersion: krm.kcl.dev/v1alpha1
kind: KCLRun
metadata:
  name: set-annotation
spec:
  params:
    annotations:
      managed-by: kcl-operator
  # Resource modification can be achieved with just one line of KCL code
  source: |
    items = [item | {metadata.annotations: option("params").annotations} for item in option("items")]

We have provided more than 30 built-in models, and you can find more code examples in the following link: https://github.com/kcl-lang/krm-kcl/tree/main/examples

IDE Extension Updates​

In the past two weeks, we have integrated the KCL language server LSP into NeoVim and Idea, enabling the completion, navigation, and hover features supported by VS Code IDE in NeoVim and IntelliJ IDEA.

  • NeoVim KCL Extension

kcl.nvim

  • IntelliJ Extension

intellij

For more information on downloading, installation, and features of the IDE plugins, please refer to:

Resources​

❤️ Thanks to all KCL users and community members for their valuable feedback and suggestions in the community.

For more resources, please refer to

· 3 min read

News Flash​

jakezhu9

🎉 Recently, the KCL community welcomed a new member as a Maintainer. Congratulations to jakezhu9 on successfully being promoted as a community maintainer.

We would like to express our gratitude for his numerous contributions to the KCL Go SDK and the series of enhanced features he has brought to the KCL Import Tool, providing users with a more convenient and efficient experience in importing data and schemas. Here is a list of his recent significant contributions:

The addition of the new Maintainer not only signifies jakezhu9's outstanding technical performance but also reflects the community's high recognition and trust in him.

Experience​

Here are jakezhu9's reflections on participating in the KCL community:

I feel incredibly fortunate to be a part of the KCL community and contribute to the development and growth of the project. From the initial introduction to the KusionStack and KCL, powerful tools and languages in the cloud-native field, to fixing a simple bug in the project, and gradually designing and developing the conversion and generation aspects of KCL, I have not only improved my technical skills but also gained valuable experience in open-source contributions. I have experienced the joy and sense of accomplishment that comes with continuous progress. Every time I see one of my submitted PRs get merged, I feel a great sense of satisfaction. I am grateful to the KCL community and all the seniors and fellow contributors I have encountered along the way who have provided me with ideas and suggestions that have been incredibly helpful during my development process.

The KCL community is an open, vibrant, and opportune open-source community where developers from different companies and schools with diverse technical backgrounds collaborate and exchange ideas on GitHub and in community meetings. Together, they explore cutting-edge technical solutions and contribute efficient and concise code to the community. Whether you are a novice or an expert in open-source, you can quickly integrate into the community and actively participate. The harmonious and friendly atmosphere in the community makes me feel incredibly welcomed. In the future, I will continue to contribute more to the KCL community, and I warmly welcome interested students to join us and participate in the construction and development of the community together!

Resources​

For more resources, please refer to