23 | 稳定性实践：容量规划之压测系统建设

// k6-test.js
import http from 'k6/http';
import { check, sleep } from 'k6';
import { Trend, Rate, Counter } from 'k6/metrics';

// 自定义指标
const responseTime = new Trend('http_req_duration_custom');
const errorRate = new Rate('errors');
const requestCount = new Counter('requests');

// 测试配置
export const options = {
  stages: [
    { duration: '2m', target: 100 },   // 预热：逐步到100并发
    { duration: '5m', target: 500 },   // 加压：到500并发
    { duration: '10m', target: 1000 }, // 高峰：保持1000并发
    { duration: '3m', target: 100 },   // 恢复：降到100并发
  ],
  thresholds: {
    http_req_duration: ['p(95)<500', 'p(99)<1000'],  // P95<500ms, P99<1s
    errors: ['rate<0.01'],                             // 错误率<1%
    http_reqs: ['count>10000'],                        // 总请求数>1万
  },
};

// 输出集成：k6 指标可通过 --out 导出到 InfluxDB/Prometheus 远程写入，再由 Grafana 展示
export function setup() {
  return { testStartTime: new Date().toISOString() };
}

export default function (data) {
  const payload = JSON.stringify({
    user_id: `user_${__VU}`,
    product_id: `prod_${Math.floor(Math.random() * 1000)}`,
    quantity: Math.floor(Math.random() * 5) + 1,
    timestamp: Date.now(),
  });

  const params = {
    headers: {
      'Content-Type': 'application/json',
      'X-Load-Test': 'true',
      'X-Test-Scenario': 'order-create',
    },
  };

  const res = http.post('http://order-service:8080/api/v1/orders', payload, params);

  check(res, {
    'status is 201': (r) => r.status === 201,
    'response time < 500ms': (r) => r.timings.duration < 500,
    'has order_id': (r) => JSON.parse(r.body).order_id !== undefined,
  }) || errorRate.add(1);

  responseTime.add(res.timings.duration);
  requestCount.add(1);

  sleep(Math.random() * 2);  // 模拟用户思考时间
}

# Istio VirtualService: 流量镜像用于压测
apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: order-service-vs
  namespace: production
spec:
  hosts:
  - order-service
  http:
  - match:
    - headers:
        x-load-test:
          exact: "true"
    route:
    - destination:
        host: order-service-canary
        subset: v2
      weight: 100
  - route:
    - destination:
        host: order-service
        subset: v1
      weight: 90
    - destination:
        host: order-service
        subset: canary
      weight: 10
    mirror:
      host: order-service-canary
      subset: v2
    mirrorPercentage:
      value: 100.0

# Chaos Toolkit: 全链路压测 + 故障注入组合实验
version: 1.0.0
title: Full-chain Load Test with Fault Injection
steady-state-hypothesis:
  title: System handles load under fault conditions
  probes:
  - name: order-success-rate
    type: probe
    tolerance: 200  # 校验Prometheus查询接口返回HTTP 200；对响应体中的指标值断言需配合自定义provider处理
    provider:
      type: http
      timeout: 5
      url: http://prometheus:9090/api/v1/query?query=sum(rate(http_requests_total{job="order-service",code!~"5.."}[1m]))/sum(rate(http_requests_total{job="order-service"}[1m]))
method:
- type: action
  name: start-load-test
  provider:
    type: process
    path: k6
    arguments:
    - run
    - --out
    - influxdb=http://influxdb:8086/k6data
    - tests/full-chain-test.js