「架构师训练营」作业：第 7 周

public class StressTesting
{
    private IRestClient _RestClient;
    private ConcurrentQueue<long> _ResponseTime;
    /// <summary>
    /// 并发数
    /// </summary>
    private int _concurrentNumber;
    /// <summary>
    /// 请求数
    /// </summary>
    private int _requestQuantity;
    private string _url;
    public StressTesting(string url,int concurrentNumber,int requestQuantity)
    {
        _url = url;
        _concurrentNumber = concurrentNumber;
        _requestQuantity = requestQuantity;
        _RestClient = new RestClient();           
    }
     /// <summary>
     /// 并发测试
     /// </summary>
     public void DoTest()
     {
         _ResponseTime = new ConcurrentQueue<long>();
         var parallelOptions = new ParallelOptions()
         {
             MaxDegreeOfParallelism = _concurrentNumber
         };
         Parallel.For(0, _requestQuantity, parallelOptions, (i) =>
          {
              DoRequest();
          });
          ShowResult();
      }
      /// <summary>
      /// 一次请求
      /// </summary>
      private void DoRequest()
      {
          var stopwatch = new Stopwatch();
          var request = new RestRequest(_url, Method.GET);
          stopwatch.Start();
          _RestClient.Execute(request);
          stopwatch.Stop();
          _ResponseTime.Enqueue(stopwatch.ElapsedMilliseconds);
     }
     /// <summary>
     /// 展示结果
     /// </summary>
     private void ShowResult()
     {
         double avgTime = _ResponseTime.Average();
         double avg95Time = Calculate95Avg();
          Console.WriteLine(_url);
          Console.WriteLine("并发：{0}",_concurrentNumber);
          Console.WriteLine("请求次数：{0}",_requestQuantity);
          Console.WriteLine("结果：");
          Console.WriteLine("平均响应时间：{0}", avgTime);
          Console.WriteLine("95%响应时间：{0}", avg95Time);
      }
      /// <summary>
      /// 计算 95% 响应时间
      /// </summary>
      /// <returns></returns>
      private double Calculate95Avg()
      {
          double result = 0;
          long[] values = _ResponseTime.ToArray();
            
          double stdDev = 0;
          double avg = values.Average();
          double sum = values.Sum(d => Math.Pow(d - avg, 2));
          stdDev = Math.Sqrt(sum / values.Count());
          result = avg + (-stdDev) * 1.96 / Math.Sqrt(values.Count());
          return result;
      }
}

class Program
{
    static void Main(string[] args)
    {
        try
        {
            var test = new StressTesting("https://www.baidu.com/",10,100);
            test.DoTest();
         }
         catch (Exception ex)
         {
             Console.WriteLine(ex.ToString());
         }
         Console.WriteLine("---------------- End ---------------------");
         Console.ReadLine();
    }
}