几次重试策略.Net Core后更改失败的域

Question

我有这段代码，我正在使用 Polly 处理失败的网络请求，我想知道是否有办法在使用 polly 进行几次故障转移后将域从 https://www.api1.com 更改为 https://www.api2.com，

var logger = new LoggerConfiguration()
    .MinimumLevel.Verbose()
    .Enrich.FromLogContext()
    .WriteTo.ColoredConsole()
    .CreateLogger();

var httpClient = new HttpClient();
var response = await Policy
    .HandleResult<HttpResponseMessage>(message => !message.IsSuccessStatusCode)
    .WaitAndRetryAsync(3, i => TimeSpan.FromSeconds(2), (result, timeSpan, retryCount, context) =>
    {
        logger.Warning($"Request failed with {result.Result.StatusCode}. Waiting {timeSpan} before 
                         next retry. Retry attempt {retryCount}");
    })
    .ExecuteAsync(() => httpClient.GetAsync("https://www.api1.com"));

if (response.IsSuccessStatusCode)
    logger.Informa`enter code here`tion("Response was successful.");
else
    logger.Error($"Response failed. Status code {response.StatusCode}");

提前谢谢你！

Answer 1

忽略任何其他概念或其他问题。一种方法是简单地更改 WaitAndRetryAsync

中的 url

随之而来的是低技术方法

var url1 = "https://postman-echo.com/status/500";
var url2 = "https://postman-echo.com/status/200";

var currentUrl = url1;

var httpClient = new HttpClient();

var response = await Policy
   .HandleResult<HttpResponseMessage>(message => !message.IsSuccessStatusCode)
   .WaitAndRetryAsync(3, i => TimeSpan.FromSeconds(2), (result, timeSpan, retryCount, context) =>
   {
      Console.WriteLine($"Request failed with {result.Result.StatusCode}. Waiting {timeSpan} before next retry.Retry attempt { retryCount}");
      if (retryCount > 2)
      {
         currentUrl = url2;
         Console.WriteLine("Changing to " + currentUrl);
      }
   })
   .ExecuteAsync(() =>
   {
      Console.WriteLine(currentUrl);
      return httpClient.GetAsync(currentUrl);
   });

输出

https://postman-echo.com/status/500
Request failed with InternalServerError. Waiting 00:00:02 before next retry.Retry attempt 1
https://postman-echo.com/status/500
Request failed with InternalServerError. Waiting 00:00:02 before next retry.Retry attempt 2
https://postman-echo.com/status/500
Request failed with InternalServerError. Waiting 00:00:02 before next retry.Retry attempt 3
Changing to https://postman-echo.com/status/200
https://postman-echo.com/status/200

_{免责声明：这并不是完美代码或完整解决方案的堡垒。加入胡椒和盐调味，并尽职尽责。 ¯\_(ツ)_/¯}