# 创建蓝绿环境目录
mkdir -p /opt/bluegreen/{blue,green,conf}

# 蓝环境（当前线上v1）
cat > /opt/bluegreen/blue/index.html << 'EOF'
🔵 蓝环境 v1.0 - 当前线上
EOF

# 绿环境（新版本v2）
cat > /opt/bluegreen/green/index.html << 'EOF'
🟢 绿环境 v2.0 - 新版本
EOF

# Nginx配置——指向蓝环境
cat > /opt/bluegreen/conf/nginx.conf << 'EOF'
upstream active_env {
    server 127.0.0.1:8081;  # blue
}
server {
    listen 80;
    location / {
        proxy_pass http://active_env;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}
EOF

# 切换到绿环境脚本
cat > /opt/bluegreen/switch-to-green.sh << 'SCRIPT'
#!/bin/bash
set -euo pipefail
echo "🟢 切换到绿环境..."
if ! curl -sf http://127.0.0.1:8082/health > /dev/null; then
    echo "❌ 绿环境健康检查失败！"; exit 1
fi
sed -i 's/server 127.0.0.1:8081.*# blue/server 127.0.0.1:8082;  # green/'     /opt/bluegreen/conf/nginx.conf
nginx -t && nginx -s reload
echo "✅ 已切换到绿环境"
SCRIPT
chmod +x /opt/bluegreen/switch-to-green.sh

# 回滚到蓝环境
cat > /opt/bluegreen/switch-to-blue.sh << 'SCRIPT'
#!/bin/bash
sed -i 's/server 127.0.0.1:8082.*# green/server 127.0.0.1:8081;  # blue/'     /opt/bluegreen/conf/nginx.conf
nginx -t && nginx -s reload
echo "✅ 已回滚到蓝环境"
SCRIPT
chmod +x /opt/bluegreen/switch-to-blue.sh

# 蓝环境Deployment
cat > blue-deployment.yaml << 'EOF'
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-blue
  labels:
    app: myapp
    slot: blue
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
      slot: blue
  template:
    metadata:
      labels:
        app: myapp
        slot: blue
    spec:
      containers:
      - name: myapp
        image: myregistry/myapp:v1.0
        ports:
        - containerPort: 8080
        readinessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 10
EOF

# 绿环境Deployment（仅改slot和image）
cat > green-deployment.yaml << 'EOF'
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-green
  labels:
    app: myapp
    slot: green
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
      slot: green
  template:
    metadata:
      labels:
        app: myapp
        slot: green
    spec:
      containers:
      - name: myapp
        image: myregistry/myapp:v2.0
        ports:
        - containerPort: 8080
        readinessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 10
EOF

# Service——通过selector切换
cat > service.yaml << 'EOF'
apiVersion: v1
kind: Service
metadata:
  name: myapp-svc
spec:
  selector:
    app: myapp
    slot: blue    # ← 切换时改为green
  ports:
  - port: 80
    targetPort: 8080
  type: ClusterIP
EOF

kubectl apply -f blue-deployment.yaml
kubectl apply -f green-deployment.yaml
kubectl apply -f service.yaml

# 切换到绿环境
kubectl patch svc myapp-svc -p '{"spec":{"selector":{"slot":"green"}}}'

# 回滚到蓝环境
kubectl patch svc myapp-svc -p '{"spec":{"selector":{"slot":"blue"}}}'

#!/bin/bash
# bluegreen-deploy.sh — 完整蓝绿部署自动化
set -euo pipefail
NAMESPACE="${1:-default}"
APP_NAME="myapp"
IMAGE_TAG="${2:?Usage: $0  }"

log() { echo "[$(date '+%H:%M:%S')] $*"; }

get_active_slot() {
    kubectl get svc myapp-svc -n "$NAMESPACE" -o jsonpath='{.spec.selector.slot}'
}

deploy_inactive() {
    local inactive="$1"
    log "部署 ${APP_NAME}-${inactive} (${IMAGE_TAG})..."
    kubectl set image deployment/"${APP_NAME}-${inactive}"         myapp="myregistry/${APP_NAME}:${IMAGE_TAG}" -n "$NAMESPACE"
    kubectl rollout status deployment/"${APP_NAME}-${inactive}"         -n "$NAMESPACE" --timeout=300s
}

health_check() {
    log "健康检查..."
    for i in $(seq 1 30); do
        if curl -sf "http://myapp-svc.$NAMESPACE.svc.cluster.local/health" > /dev/null 2>&1; then
            log "健康检查通过 ✅"; return 0
        fi
        log "等待就绪... ($i/30)"; sleep 5
    done
    log "❌ 健康检查超时"; return 1
}

switch_traffic() {
    local target="$1"
    log "切换流量到 $target..."
    kubectl patch svc myapp-svc -n "$NAMESPACE"         -p "{"spec":{"selector":{"slot":"${target}"}}}"
    log "流量切换完成 ✅"
}

main() {
    local active=$(get_active_slot)
    local inactive=$([[ "$active" == "blue" ]] && echo "green" || echo "blue")
    log "当前活跃: $active, 部署到: $inactive"
    deploy_inactive "$inactive"
    if ! health_check; then
        log "❌ 失败，保持 $active"; exit 1
    fi
    switch_traffic "$inactive"
    log "✅ 完成！回滚命令：kubectl patch svc myapp-svc -n $NAMESPACE -p '{"spec":{"selector":{"slot":"$active"}}}'"
}
main "$@"