private async Task <MultiShardDataReader> ExecAsync(MultiShardConnection conn, MultiShardCommand cmd)
{
cmd.ExecutionPolicy = MultiShardExecutionPolicy.PartialResults;
cmd.ExecutionOptions = MultiShardExecutionOptions.IncludeShardNameColumn;
return(await cmd.ExecuteReaderAsync(CommandBehavior.Default, CancellationToken.None));
}
private static async Task <int> ExecuteReader(MultiShardCommand command)
{
var rows = 0;
using (var reader = await command.ExecuteReaderAsync())
{
while (await reader.ReadAsync())
{
rows++;
}
}
return(rows);
}
public void TestQueryShardsCommandCancellationHandler()
{
List <ShardLocation> cancelledShards = new List <ShardLocation>();
CancellationTokenSource cts = new CancellationTokenSource();
using (MultiShardCommand cmd = _shardConnection.CreateCommand())
{
Barrier barrier = new Barrier(cmd.Connection.Shards.Count() + 1);
// If the threads don't meet the barrier by this time, then give up and fail the test
TimeSpan barrierTimeout = TimeSpan.FromSeconds(10);
cmd.CommandText = "WAITFOR DELAY '00:01:00'";
cmd.CommandTimeoutPerShard = 12;
cmd.ShardExecutionCanceled += (obj, args) =>
{
cancelledShards.Add(args.ShardLocation);
};
cmd.ShardExecutionBegan += (obj, args) =>
{
// If ShardExecutionBegan were only signaled by one thread,
// then this would hang forever.
barrier.SignalAndWait(barrierTimeout);
};
Task cmdTask = cmd.ExecuteReaderAsync(cts.Token);
bool syncronized = barrier.SignalAndWait(barrierTimeout);
Assert.IsTrue(syncronized);
// Cancel the command once execution begins
// Sleeps are bad but this is just to really make sure
// sqlclient has had a chance to begin command execution
// Will not effect the test outcome
Thread.Sleep(TimeSpan.FromSeconds(1));
cts.Cancel();
// Validate that the task was cancelled
AssertExtensions.WaitAndAssertThrows <TaskCanceledException>(cmdTask);
// Validate that the cancellation event was fired for all shards
List <ShardLocation> allShards = _shardConnection.GetShardConnections().Select(l => l.Item1).ToList();
CollectionAssert.AreEquivalent(allShards, cancelledShards, "Expected command canceled event to be fired for all shards!");
}
}
private async Task<MultiShardDataReader> ExecAsync(MultiShardConnection conn, MultiShardCommand cmd)
{
cmd.ExecutionPolicy = MultiShardExecutionPolicy.PartialResults;
cmd.ExecutionOptions = MultiShardExecutionOptions.IncludeShardNameColumn;
return await cmd.ExecuteReaderAsync(CommandBehavior.Default, CancellationToken.None);
}