架构师训练营第 0 期第 7 周作业

// web-stress-testing.go
package stress_testing
import (
	"net/http"
	"sort"
	"sync"
	"time"
)
type StressTestingRunner interface {
	Run(url string, request int, concurrent int) (int64, int64)
}
type WebStressTestingRunner struct {
}
func NewStressTestingRunner() StressTestingRunner {
	return &WebStressTestingRunner{}
}
func (r *WebStressTestingRunner) Run(url string, request int, concurrent int) (int64, int64) {
	elapsedTimes := make([]time.Duration, 0, request)
	for i := 0; i < request/concurrent; i++ {
		elapsedTimes = append(elapsedTimes, r.run(url, concurrent)...)
	}
	if request%concurrent > 0 {
		elapsedTimes = append(elapsedTimes, r.run(url, request%concurrent)...)
	}
	elapsedNanoseconds := make([]int64, request)
	for i, elapsed := range elapsedTimes {
		elapsedNanoseconds[i] = elapsed.Nanoseconds()
	}
	sort.Slice(elapsedNanoseconds, func(i, j int) bool {
		return elapsedNanoseconds[i] < elapsedNanoseconds[j]
	})
	var sum int64
	for _, elapsed := range elapsedNanoseconds {
		sum += elapsed
	}
	p50 := sum / int64(request)
	p95 := elapsedNanoseconds[int(float64(request)*0.95)-1]
	return p50, p95
}
func (r *WebStressTestingRunner) run(url string, request int) []time.Duration {
	wg := sync.WaitGroup{}
	elapsedTimes := make([]time.Duration, 0, request)
	for i := 0; i < request; i++ {
		wg.Add(1)
		go func() {
			start := time.Now()
			// ignore response and error
			http.Get(url)
			elapsedTimes = append(elapsedTimes, time.Since(start))
			wg.Done()
		}()
	}
	wg.Wait()
	return elapsedTimes
}
// web-stress-testing_test.go
package stress_testing
import "testing"
func TestWebStressTestingRunner_Run(t *testing.T) {
	runner := NewStressTestingRunner()
	url := "https://www.baidu.com"
	request := 100
	concurrent := 10
	for i := 0; i < 5; i++ {
		p50, p95 := runner.Run(url, request, concurrent)
		t.Logf("WebStressTesting: url=%s, request=%d, concurrent=%d, p50=%dns, p95=%dns\n", url, request, concurrent, p50, p95)
	}
}
// output
=== RUN   TestWebStressTestingRunner_Run
    TestWebStressTestingRunner_Run: web-stress-testing_test.go:12: WebStressTesting: url=https://www.baidu.com, request=100, concurrent=10, p50=166807071ns, p95=467995313ns
    TestWebStressTestingRunner_Run: web-stress-testing_test.go:12: WebStressTesting: url=https://www.baidu.com, request=100, concurrent=10, p50=386995794ns, p95=1422057192ns
    TestWebStressTestingRunner_Run: web-stress-testing_test.go:12: WebStressTesting: url=https://www.baidu.com, request=100, concurrent=10, p50=106412302ns, p95=151324861ns
    TestWebStressTestingRunner_Run: web-stress-testing_test.go:12: WebStressTesting: url=https://www.baidu.com, request=100, concurrent=10, p50=267705842ns, p95=1020937437ns
    TestWebStressTestingRunner_Run: web-stress-testing_test.go:12: WebStressTesting: url=https://www.baidu.com, request=100, concurrent=10, p50=126596884ns, p95=158419194ns
--- PASS: TestWebStressTestingRunner_Run (14.22s)
PASS
Process finished with exit code 0