public async Task <R> ExecOnNearServerAsync_4 <S, R>(ITAPServices <S, R> svc, Uri[] servers, S service)
{
Task <Uri>[] tasks = new Task <Uri> [servers.Length];
for (int i = 0; i < servers.Length; ++i)
{
tasks[i] = svc.PingServerAsync(servers[i]);
}
Task.Factory.ContinueWhenAll(tasks, (antecedents) => {
try { Task.WaitAll(antecedents); } catch { /*** log any thrown exceptions ***/ }
});
return(await svc.ExecServiceAsync(await Task.WhenAny(tasks).Result, service));
}
public Task <R> ExecOnNearServerAsync <S, R>(ITAPServices <S, R> svc, Uri[] servers, S service)
{
Task <Uri>[] pingTasks = new Task <Uri> [servers.Length];
for (int i = 0; i < servers.Length; ++i)
{
pingTasks[i] = svc.PingServerAsync(servers[i]);
}
return(Task.Factory.ContinueWhenAny(pingTasks, (ant) =>
{
pingTasks = pingTasks.Where(t => t != ant).ToArray();
Task.Factory.ContinueWhenAll(pingTasks, (ant2) =>
{
try
{
Task.WaitAll(ant2);
}
catch { }
});
return svc.ExecServiceAsync(ant.Result, service);
}).Unwrap());
}
public async Task <R> ExecOnNearServerAsync_5 <S, R>(ITAPServices <S, R> svc, Uri[] servers, S service)
{
Task <Uri>[] pingTasks = new Task <Uri> [servers.Length];
for (int i = 0; i < servers.Length; ++i)
{
pingTasks[i] = svc.PingServerAsync(servers[i]);
}
do
{
Task <Uri> pingTask = await Task.WhenAny(pingTasks);
pingTasks = pingTasks.Where(t => t != pingTask).ToArray();
try
{
Uri uri = pingTask.Result;
Task.Factory.ContinueWhenAll(pingTasks, (ant) =>
{
try
{
Task.WaitAll(ant);
}
catch
{
}
});
return(await svc.ExecServiceAsync(uri, service));
}
catch (AggregateException ae)
{
if (pingTasks.Length == 0)
{
throw ae.InnerException;
}
}
} while (true);
}
