k8s-yaml-connect

# Kubernetes YAML Connect Skill This skill enables connection to Kubernetes clusters using YAML configuration files as input. It provides tools to apply, validate, and manage Kubernetes resources through kubectl commands. ## When to Use Use this skill when: - You have Kubernetes YAML configuration files that need to be applied to a cluster - You need to validate YAML syntax before deployment - You want to create or update kubeconfig from YAML input - You need to switch between Kubernetes contexts - You want to check cluster status and resources ## Prerequisites ### Required - `kubectl` must be installed and available in PATH - Kubernetes cluster accessible (local or remote) - Appropriate permissions for the target cluster ### Installing kubectl If kubectl is not installed, you can install it using: **macOS:** ```bash # Using Homebrew brew install kubectl # Or download directly curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/darwin/amd64/kubectl" chmod +x kubectl sudo mv kubectl /usr/local/bin/ ``` **Linux:** ```bash # Using package manager (Ubuntu/Debian) sudo apt-get update sudo apt-get install -y kubectl # Or download directly curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl" chmod +x kubectl sudo mv kubectl /usr/local/bin/ ``` **Windows:** ```powershell # Using Chocolatey choco install kubernetes-cli # Or download from official release ``` **Verify installation:** ```bash kubectl version --client ``` ## Core Workflow ### 1. Validate YAML Syntax Before applying any YAML, always validate the syntax: ```bash kubectl apply --dry-run=client -f - <<'EOF' [YAML_CONTENT] EOF ``` ### 2. Apply YAML to Cluster Apply validated YAML to the current context: ```bash kubectl apply -f - <<'EOF' [YAML_CONTENT] EOF ``` ### 3. Create/Update Kubeconfig from YAML If you have kubeconfig YAML, save it and update context: ```bash # Save kubeconfig cat > /tmp/kubeconfig.yaml <<'EOF' [KUBECONFIG_YAML] EOF # Set KUBECONFIG environment variable export KUBECONFIG=/tmp/kubeconfig.yaml # Verify connection kubectl cluster-info ``` ### 4. Context Management List and switch contexts: ```bash # List available contexts kubectl config get-contexts # Switch to specific context kubectl config use-context [CONTEXT_NAME] # Get current context kubectl config current-context ``` ## Common Operations ### Deploy a Deployment ```yaml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-deployment spec: replicas: 3 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:1.14.2 ports: - containerPort: 80 ``` ### Create a Service ```yaml apiVersion: v1 kind: Service metadata: name: nginx-service spec: selector: app: nginx ports: - protocol: TCP port: 80 targetPort: 80 type: LoadBalancer ``` ### Create a ConfigMap ```yaml apiVersion: v1 kind: ConfigMap metadata: name: app-config data: APP_ENV: "production" LOG_LEVEL: "info" ``` ## Error Handling ### Check for Common Issues ```bash # Check if kubectl is installed command -v kubectl # Check cluster connectivity kubectl version --short # Check if context is set kubectl config view --minify ``` ### Validate YAML Before Applying Always use dry-run first to catch errors: ```bash kubectl apply --dry-run=client -f [FILE_OR_STDIN] ``` ## Security Considerations 1. **Never commit sensitive data** in YAML files (use Secrets or external config) 2. **Validate YAML from untrusted sources** before applying 3. **Use namespaces** to isolate resources 4. **Apply least privilege** RBAC permissions ## Examples ### Example 1: Apply Simple Deployment ```bash # YAML content as variable YAML_CONTENT=$(cat <<'EOF' apiVersion: apps/v1 kind: Deployment metadata: name: test-deployment spec: replicas: 2 selector: matchLabels: app: test template: metadata: labels: app: test spec: containers: - name: test image: nginx:alpine EOF ) # Apply to cluster kubectl apply -f - <<< "$YAML_CONTENT" ``` ### Example 2: Multi-resource YAML ```bash kubectl apply -f - <<'EOF' --- apiVersion: v1 kind: ConfigMap metadata: name: app-config data: key: value --- apiVersion: apps/v1 kind: Deployment metadata: name: app-deployment spec: replicas: 2 selector: matchLabels: app: myapp template: metadata: labels: app: myapp spec: containers: - name: app image: myapp:latest envFrom: - configMapRef: name: app-config EOF ``` ## References For more detailed information, see: - [Kubernetes Official Documentation](https://kubernetes.io/docs/) - [kubectl Cheat Sheet](https://kubernetes.io/docs/reference/kubectl/cheatsheet/) - [YAML Best Practices](https://kubernetes.io/docs/concepts/configuration/overview/) ## Troubleshooting ### Common Issues 1. **Connection refused**: Check if cluster is running and accessible 2. **Unauthorized**: Verify kubeconfig and permissions 3. **YAML syntax error**: Validate YAML with `kubectl apply --dry-run` 4. **Resource already exists**: Use `kubectl apply` for updates or `kubectl replace` for forced updates ### Debug Commands ```bash # Get detailed error information kubectl describe [RESOURCE_TYPE] [RESOURCE_NAME] # Check events kubectl get events --sort-by='.lastTimestamp' # Check pod logs kubectl logs [POD_NAME] ``` Remember: Always test YAML in a non-production environment first when possible.