asp.net – 调用HttpClient.GetAsync时出错：基础连接已关闭

我有一个asp.net MVC网站,它正在消耗一个休息的api来接收它的数据.我正在使用异步任务执行请求,因为每个页面上可能有很多.经过一段时间的正常运行时间,网站在尝试接收数据时一直抛出以下错误.

基础连接已关闭：发送时发生意外错误.

我读到这可能是由于web.config上的最大连接设置,但增加这似乎并没有太大的区别.

我也使用缓存来减少api的负载.任务被缓存,结果可以在以后使用.

我发现解决这个问题的唯一方法是回收应用程序池.任何帮助将不胜感激.

/* Code from page_load */

var currenciesTask = ApiClient.GetAsync<CurrencyListWrapper>("currencies");
var blogArticleTask = ApiClient.GetAsync<BlogArticleListWrapper>("blog/articles","limit=10");
var SEOPageTask = ApiClient.GetAsync<SEOPageListWrapper>("SEOpages");

await Task.WhenAll(currenciesTask,blogArticleTask,SEOPageTask);


/* Code from data access later */

public class ApiClient : HttpClient
{
  public static Task<T> GetAsync<T>(string operation,string query = null,bool cache = true)
  {
    // Check if task is in cache
    string cacheName = null;

    if (cache)
    {
      cacheName = String.Format("{0}_{1}_{2}",operation,query ?? String.Empty,App.GetLanguage());

      var cachedTask = HttpRuntime.Cache[cacheName];

      if (cachedTask != null)
      {
        return (Task<T>)cachedTask;
      }

    }

    // Get data task
    var task = GetAsyncData<T>(operation,query);

    // Add to cache if required
    if (task != null && cache)
    {
      App.AddToCache(cacheName,task);
    }

    return task;
  }

  public static async Task<T> GetAsyncData<T>(string operation,string query = null)
  {
    using (ApiClient client = new ApiClient())
    {
      string url;

      if (query != null)
      {
        url = String.Format("{0}?{1}",query);
      }
      else
      {
        url = String.Format("{0}",operation);
      }

      var response = await client.GetAsync(url);

      return (await response.Content.ReadAsAsync<T>());
    }
  }
}

解决方法

The task is cached so the result can be used later.

你应该缓存结果,而不是任务.在第一次执行结束时,您的HttpClient关闭,当您尝试检索缓存任务时,它将无法正常工作.

public class ApiClient : HttpClient
{
  public static async Task<T> GetAsync<T>(string operation,App.GetLanguage());

      T cachedResult = (T)HttpRuntime.Cache[cacheName];

      if (cachedResult!= null)
      {
        return Task.FromResult(cachedResult);
      }

    }

    // Get data task
    var result = await GetAsyncData<T>(operation,query);

    // Add to cache if required
    if (result != null && cache)
    {
      App.AddToCache(cacheName,result);
    }

    return result;
  }

  public static async Task<T> GetAsyncData<T>(string operation,operation);
      }

      var response = await client.GetAsync(url);

      return (await response.Content.ReadAsAsync<T>());
    }
  }
}

（编辑：安卓应用网）

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