可以直接执行的操作手册

# 第一步：安装工具（Mac）
brew install minikube kubectl

# Windows 用户用这个
# choco install minikube kubernetes-cli

# 第二步：启动本地 K8s 集群
minikube start --cpus=2 --memory=4096

# 验证成功
kubectl get nodes
# 看到这个就对了：
# NAME       STATUS   ROLES           AGE   VERSION
# minikube   Ready    control-plane   1m    v1.28.0

# 第三步：部署你的第一个服务（用现成的 nginx 练手）
kubectl create deployment nginx --image=nginx
kubectl expose deployment nginx --port=80 --type=NodePort

# 访问它
minikube service nginx --url
# 浏览器打开输出的地址，看到 nginx 欢迎页就成功了

# 第四步：看看刚才发生了什么
kubectl get deployments
kubectl get pods
kubectl get services

# app.py
from fastapi import FastAPI
app = FastAPI()

@app.get("/health")
def health():
    return {"status": "ok", "service": "fleet-api"}

@app.get("/vehicles/{vid}")
def get_vehicle(vid: str):
    return {"id": vid, "battery": 85, "online": True}

# Dockerfile
FROM python:3.11-slim
WORKDIR /app
RUN pip install fastapi uvicorn
COPY app.py .
CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "8080"]

# 用 minikube 自带的 Docker（关键！不然镜像找不到）
eval $(minikube docker-env)
docker build -t fleet-api:v1 .

# fleet.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: fleet-api
spec:
  replicas: 2
  selector:
    matchLabels:
      app: fleet-api
  template:
    metadata:
      labels:
        app: fleet-api
    spec:
      containers:
      - name: fleet-api
        image: fleet-api:v1
        imagePullPolicy: Never      # 用本地镜像
        ports:
        - containerPort: 8080
        resources:
          requests:
            memory: "64Mi"
            cpu: "100m"
          limits:
            memory: "128Mi"
            cpu: "200m"
        readinessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 3
---
apiVersion: v1
kind: Service
metadata:
  name: fleet-api
spec:
  selector:
    app: fleet-api
  ports:
  - port: 80
    targetPort: 8080
  type: NodePort

kubectl apply -f fleet.yaml
kubectl get pods                    # 等 STATUS 变成 Running
minikube service fleet-api --url    # 访问你自己的服务
curl <url>/health
curl <url>/vehicles/v001

# config.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: fleet-config
data:
  LOG_LEVEL: "INFO"
  MAX_VEHICLES: "1000"
---
apiVersion: v1
kind: Secret
metadata:
  name: fleet-secret
type: Opaque
stringData:
  DB_PASSWORD: "my-secret-password"

# 在 Deployment 的 containers 里加上：
        env:
        - name: LOG_LEVEL
          valueFrom:
            configMapKeyRef:
              name: fleet-config
              key: LOG_LEVEL
        - name: DB_PASSWORD
          valueFrom:
            secretKeyRef:
              name: fleet-secret
              key: DB_PASSWORD

# 故障一：ImagePullBackOff
# 制造故障
kubectl set image deployment/fleet-api fleet-api=fleet-api:v999
kubectl get pods    # 看到 ImagePullBackOff

# 排查
kubectl describe pod <pod-name>
# 看 Events 段，会看到：
# Failed to pull image "fleet-api:v999": not found

# 恢复
kubectl set image deployment/fleet-api fleet-api=fleet-api:v1

# 故障二：OOMKilled
# 把内存限制改得极小
kubectl set resources deployment/fleet-api \
  --limits=memory=1Mi
kubectl get pods    # 看到 OOMKilled 或 CrashLoopBackOff

# 排查
kubectl describe pod <pod-name>
# 看到：Last State: Terminated, Reason: OOMKilled

# 恢复
kubectl set resources deployment/fleet-api \
  --limits=memory=128Mi

# 故障三：服务不通
# 把 Service 的 selector 改错
kubectl edit service fleet-api
# 把 app: fleet-api 改成 app: wrong-label
kubectl get endpoints fleet-api
# 看到 ENDPOINTS 是 <none>，说明没有 Pod 匹配

# 故障四：手动删 Pod，验证自愈
kubectl delete pod <pod-name>
kubectl get pods -w    # 看到新 Pod 立刻被创建

# 滚动更新
# 修改 app.py，改个返回值，重新构建
eval $(minikube docker-env)
docker build -t fleet-api:v2 .

kubectl set image deployment/fleet-api fleet-api=fleet-api:v2
kubectl rollout status deployment/fleet-api  # 看更新过程
kubectl rollout history deployment/fleet-api # 看版本历史

# 出问题了，回滚
kubectl rollout undo deployment/fleet-api
kubectl rollout status deployment/fleet-api  # 确认回滚完成

# HPA 自动扩缩容
minikube addons enable metrics-server   # 先启用指标采集

kubectl autoscale deployment fleet-api \
  --min=2 --max=10 --cpu-percent=50

kubectl get hpa    # 查看 HPA 状态

✅ 本地搭好 K8s 环境
✅ 把自己写的服务部署上去
✅ 用 ConfigMap/Secret 管理配置
✅ 看到 CrashLoopBackOff / OOMKilled 知道怎么排查
✅ 能做滚动更新和回滚
✅ 理解 HPA 自动扩缩容