private static async Task <Response[]> ExecServicesAsync(ITAPServices svc, UserId uid, Request[] requests)
{
Task <Response>[] responseTasks = new Task <Response> [requests.Length];
Session session;
try
{
session = await svc.LoginAsync(uid);
}
catch
{
//throw illegal user exception
throw;
}
for (int i = 0; i < requests.Length; i++)
{
try
{
responseTasks[i] = svc.ExecServiceAsync(session, requests[i]);
}
catch
{
//on server too busy exception
responseTasks[i] = null;
}
}
await Task.WhenAll(responseTasks);
await svc.LogoutAsync(session);
return(responseTasks.Select(task => task.Result).ToArray());
}
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));
}
/// <summary>
/// Versão original (promove o bloqueio de threads),
/// acabando por ser equivalente a um aversão síncrona
/// </summary>
/// <param name="svc"></param>
/// <param name="uid"></param>
/// <param name="requests"></param>
/// <returns></returns>
public static Task <Response[]> ExecServicesOldAsync(ITAPServices svc, UserID uid, Request[] requests)
{
return(Task.Run(() => {
Session session = svc.LoginAsync(uid).Result;
try {
Response[] responses = new Response[requests.Length];
for (int i = 0; i < requests.Length; i++)
{
responses[i] = svc.ExecServiceAsync(session, requests[i]).Result;
}
return responses;
}
finally { try { svc.LogoutAsync(session).Wait(); } catch { } }
}));
}
/// <summary>
/// Versão que optimiza o paralelismo potencial
/// </summary>
/// <param name="svc"></param>
/// <param name="uid"></param>
/// <param name="requests"></param>
/// <returns></returns>
public static async Task <Response[]> ExecServicesAsync(ITAPServices svc,
UserID uid, Request[] requests)
{
Session session = await svc.LoginAsync(uid);
try {
Task <Response>[] tasks = new Task <Response> [requests.Length];
for (int i = 0; i < requests.Length; i++)
{
tasks[i] = svc.ExecServiceAsync(session, requests[i]);
}
return(await Task.WhenAll(tasks));
}
finally { try { await svc.LogoutAsync(session); } catch { } }
}
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);
}