Merge pull request #147 from Peefy/kcl-operator-guide

feat: add kcl operator documents

Author: Peefy

docs/user_docs/guides/working-with-k8s/3-mutate-manifests/6-kcl-operator.md

@@ -0,0 +1,92 @@
+---
+title: "KCL Operator"
+sidebar_position: 6
+---
+
+## Introduction
+
+[KCL Operator](https://github.com/kcl-lang/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` resource 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.
++ **Validate** all KRM resources using KCL schema.
++ Use an abstract model to **generate** KRM resources.
+
+## Prerequisites
+
++ Install Kubectl
++ Prepare a Kubernetes cluster
+
+## Quick Start
+
+Let’s write a KCL function which add annotation `managed-by=kcl-operator` only to Pod resources at runtime.
+
+### 1. Install KCL Operator
+
+```bash
+kubectl apply -f https://raw.githubusercontent.com/kcl-lang/kcl-operator/main/config/all.yaml
+```
+
+Use the following command to watch and wait the pod status is Running.
+
+```shell
+kubectl get po
+```
+
+### 2. Deploy the KCL source
+
+```bash
+kubectl apply -f- << EOF
+apiVersion: krm.kcl.dev/v1alpha1
+kind: KCLRun
+metadata:
+  name: set-annotation
+spec:
+  source: |
+    items = [item | {
+        metadata.annotations: {
+            "managed-by" = "kcl-operator"
+        }
+    } for item in option("items")]
+EOF
+```
+
+### 3. Validate the result
+
+Validate the mutation result by creating a nginx Pod YAML.
+
+```shell
+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
+```
+
+The output is
+
+```shell
+    managed-by: kcl-operator
+```
+
+## Guides for Developing KCL
+
+Here's what you can do in the KCL code:
+
++ Read resources from `option("resource_list")`. The `option("resource_list")` complies with the [KRM Functions Specification](https://kpt.dev/book/05-developing-functions/01-functions-specification). You can read the input resources from `option("items")` and the params from `option("params")`.
++ Return a KPM list for output resources.
++ Return an error using `assert {condition}, {error_message}`.
+
+## More Documents and Examples
+
++ [KRM KCL Spec](https://github.com/kcl-lang/krm-kcl)

versioned_docs/version-0.5.5/user_docs/guides/working-with-k8s/3-mutate-manifests/6-kcl-operator.md

@@ -0,0 +1,92 @@
+---
+title: "KCL Operator"
+sidebar_position: 6
+---
+
+## Introduction
+
+[KCL Operator](https://github.com/kcl-lang/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` resource 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.
++ **Validate** all KRM resources using KCL schema.
++ Use an abstract model to **generate** KRM resources.
+
+## Prerequisites
+
++ Install Kubectl
++ Prepare a Kubernetes cluster
+
+## Quick Start
+
+Let’s write a KCL function which add annotation `managed-by=kcl-operator` only to Pod resources at runtime.
+
+### 1. Install KCL Operator
+
+```bash
+kubectl apply -f https://raw.githubusercontent.com/kcl-lang/kcl-operator/main/config/all.yaml
+```
+
+Use the following command to watch and wait the pod status is Running.
+
+```shell
+kubectl get po
+```
+
+### 2. Deploy the KCL source
+
+```bash
+kubectl apply -f- << EOF
+apiVersion: krm.kcl.dev/v1alpha1
+kind: KCLRun
+metadata:
+  name: set-annotation
+spec:
+  source: |
+    items = [item | {
+        metadata.annotations: {
+            "managed-by" = "kcl-operator"
+        }
+    } for item in option("items")]
+EOF
+```
+
+### 3. Validate the result
+
+Validate the mutation result by creating a nginx Pod YAML.
+
+```shell
+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
+```
+
+The output is
+
+```shell
+    managed-by: kcl-operator
+```
+
+## Guides for Developing KCL
+
+Here's what you can do in the KCL code:
+
++ Read resources from `option("resource_list")`. The `option("resource_list")` complies with the [KRM Functions Specification](https://kpt.dev/book/05-developing-functions/01-functions-specification). You can read the input resources from `option("items")` and the params from `option("params")`.
++ Return a KPM list for output resources.
++ Return an error using `assert {condition}, {error_message}`.
+
+## More Documents and Examples
+
++ [KRM KCL Spec](https://github.com/kcl-lang/krm-kcl)