SpinKubeでWASMアプリをKubernetesにデプロイする

# Kubernetes関連
- kubectl（Kubernetes CLI）
- Helm v3（Kubernetesパッケージマネージャー）

# 開発ツール
- Docker / Colima
- k3d または Kind（ローカルKubernetesクラスター用）

# Spinツール
- spin CLI（Spinアプリケーション開発用）
- Rust toolchain（Rustアプリケーション開発時）

% brew install kubectl helm k3d

# Docker / Colima
% brew install --cask docker
# or 
% brew install colima

# Spin CLI
% curl -fsSL https://developer.fermyon.com/downloads/install.sh | bash
% sudo mv spin /usr/local/bin/

# Rust（Spinアプリ開発用）
% curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

% K3D_FIX_DNS=0 k3d cluster create spinkube-cluster \
  --port "8081:80@loadbalancer" \
  --agents 2

# cert-managerのインストール
% kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.14.5/cert-manager.yaml

# cert-managerが起動するまで待機
% kubectl wait --for=condition=ready --timeout=300s -n cert-manager pod --all

# RuntimeClassの適用
# containerd-shim-spinを指定
% kubectl apply -f https://github.com/spinkube/containerd-shim-spin/releases/download/v0.19.0/runtime-class-manager.yaml

# CRDsの適用
% kubectl apply -f https://github.com/spinkube/spin-operator/releases/download/v0.5.0/spin-operator.crds.yaml

# Spin Operatorのインストール
% helm install spin-operator \
  oci://ghcr.io/spinkube/charts/spin-operator \
  --namespace spin-operator \
  --create-namespace \
  --version 0.5.0 \
  --wait

apiVersion: core.spinkube.dev/v1alpha1
kind: SpinAppExecutor
metadata:
  name: spintainer
spec:
  createDeployment: true
  deploymentConfig:
    installDefaultCACerts: true
    spinImage: ghcr.io/fermyon/spin:v3.0.0

% kubectl apply -f spintainer-executor.yaml

% spin plugins install kube --yes

% spin new -t http-rust hello-spinkube --accept-defaults

use spin_sdk::http::{IntoResponse, Request, Response};
use spin_sdk::http_component;

#[http_component]
fn handle_hello_spinkube(req: Request) -> anyhow::Result<impl IntoResponse> {
    let path = req.uri().path();
    
    let response = match path {
        "/" => "Welcome to SpinKube!",
        "/hello" => "Hello from WebAssembly running on Kubernetes!",
        "/health" => "OK",
        _ => "Not Found",
    };
    
    Ok(Response::builder()
        .status(200)
        .header("content-type", "text/plain")
        .body(response)
        .build())
}

# WASMターゲットの追加（初回のみ）
% rustup target add wasm32-wasip1

# Build
% spin build

# OCI registryへのプッシュ（ttl.shは1h有効なレジストリ）
% export IMAGE_NAME=ttl.sh/hello-spinkube-$(uuidgen):1h
% spin registry push $IMAGE_NAME

% spin kube scaffold --from $IMAGE_NAME > spinapp.yaml

apiVersion: core.spinkube.dev/v1alpha1
kind: SpinApp
metadata:
  name: hello-spinkube
spec:
  image: "ttl.sh/hello-spinkube-xxx:1h"  # 実際のイメージ名に置き換え
  executor: spintainer  # containerd-shim-spin から変更
  replicas: 2

% spin up --listen 127.0.0.1:3000

% curl http://127.0.0.1:3000/

Welcome to SpinKube!

% curl http://127.0.0.1:3000/hello

Hello from WebAssembly running on Kubernetes!

% curl http://127.0.0.1:3000/health
OK

# SpinAppのデプロイ
% kubectl apply -f spinapp.yaml

% kubectl get spinapp
% kubectl get pods -l core.spinkube.dev/app-name=hello-spinkube

% kubectl wait --for=condition=ready pod -l \
core.spinkube.dev/app-name=hello-spinkube --timeout=120s

# ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: hello-spinkube
  annotations:
    ingress.kubernetes.io/ssl-redirect: "false"
spec:
  rules:
  - host: hello-spinkube.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: hello-spinkube
            port:
              number: 80

% kubectl apply -f ingress.yaml

% curl -H "Host: hello-spinkube.local" http://localhost:8081/

Welcome to SpinKube! Your WebAssembly app is running on Kubernetes!