public void TestTaskHelper()
{
TaskHelper.GetUnderlyingType(typeof(Task <int>), out bool isTask).ShouldBe(typeof(int));
isTask.ShouldBe(true);
TaskHelper.GetUnderlyingType(typeof(Task), out isTask).ShouldBe(null);
isTask.ShouldBe(true);
TaskHelper.GetUnderlyingType(typeof(int), out isTask).ShouldBe(typeof(int));
isTask.ShouldBe(false);
TaskHelper.ConvertToGeneric(typeof(int), Task.FromResult <object>(1)).ShouldBeAssignableTo(typeof(Task <int>));
TaskHelper.GetResult(Task.FromResult(1)).ShouldBe(1);
TaskHelper.GetResult(Task.CompletedTask).ShouldBe(null);
}
private object ExecuteAsync(Type returnType, CobServiceDescription desc, Func <ServiceInfo, Task> action, MethodInfo method = null, Dictionary <string, object> parameters = null)
{
var retry = new ServiceTaskRetryContainer(_loggerFactory, _selector, desc.RetryTimes, desc.RetryExceptionTypes);
var taskResult = retry.RunForResult(action).ContinueWith(t => {
foreach (var item in t.Result)
{
if (item.Service != null)
{
//set exception,超过阈值后熔断
if (item.Exception != null)
{
_selector.MarkServiceFailed(item.Service, false);
}
else if (item.Duration.HasValue)
{
_selector.MarkServiceHealthy(item.Service, item.Duration.Value);
}
}
}
if (t.Result.All(i => i.Exception != null))
{
var ex = t.Result.First().Exception.GetInnerException();
//failover
//降级 fallback
if (desc.FallbackHandler != null)
{
_logger.LogInformation("使用缺省值处理类返回");
var handler = _fallbackHandlers.GetOrAdd(desc.FallbackHandler, k => Activator.CreateInstance(k) as ICobFallbackHandler);
return(handler?.GetValue(new CobFallbackHandlerContext {
ReturnType = returnType, Exception = ex, ServiceName = desc.ServiceName, Path = desc.Path, Method = method, Parameters = parameters
}));
}
else if (!string.IsNullOrWhiteSpace(desc.FallbackValue))
{
_logger.LogInformation("使用缺省值返回");
return(_scripts.GetOrAdd(desc.FallbackValue, k => CSharpScript.EvaluateAsync(k).ConfigureAwait(false).GetAwaiter().GetResult()));//todo:处理是否为Task
}
//没有缺省值时，抛出异常
throw ex;
}
return(t.Result.FirstOrDefault(i => i.Exception == null)?.Result);
});
var realType = TaskHelper.GetUnderlyingType(returnType, out bool isTask);
//匹配返回的类型
if (isTask)
{
return(TaskHelper.ConvertToGeneric(realType, taskResult));
}
else if (realType != null)
{
return(taskResult.ConfigureAwait(false).GetAwaiter().GetResult());//todo:在beforeRequest时抛出异常，这里就会一直等待？
}
return(null);//todo:change to default(T) ??
}