public async void Reuses_MessageSender_ForTheSameQueueName_OnConcurrentTasks()
{
// prepare
const string queueName = "test-queue";
int taskCount = 5;
IMessageSender[] messageSenders = new IMessageSender[taskCount];
Task[] tasks = new Task[taskCount];
for (int i = 0; i < taskCount; i++)
{
var y = i; // CLOSURE - we dont want to capture i as it is changing outside of the delegate!!!
tasks[i] = Task.Run(
() => messageSenders[y] = _messageSenderFactory.GetMessageSender(queueName));
}
// execute
await Task.WhenAll(tasks);
// test
foreach (var ms in messageSenders)
{
Assert.NotNull(ms);
}
// each message sender is for the same queue
var groupedByPath = messageSenders.GroupBy(x => x.Path);
Assert.Single(groupedByPath);
// each message sender has the same client Id
var groupedByClientId = messageSenders.GroupBy(x => x.ClientId);
Assert.Single(groupedByClientId);
// finally check that each message sender is indeed the same object
var firstMs = messageSenders[0];
for (int i = 1; i < taskCount; i++)
{
Assert.True(object.ReferenceEquals(firstMs, messageSenders[i]));
}
}
public async void Reuses_MessageSenders_ForMultipleQueueNames_OnConcurrentTasks()
{
// prepare
const string queueName0 = "test-queue-0";
const string queueName1 = "test-queue-1";
int taskCount = 6;
IMessageSender[] messageSenders = new IMessageSender[taskCount];
Task[] tasks = new Task[taskCount];
for (int i = 0; i < taskCount; i++)
{
var y = i; // CLOSURE - we dont want to capture i as it is changing outside of the delegate!!!
tasks[i] = Task.Run(
() => {
// each "even" message sender gets test-queue-0
// each "odd" message sender gets test-queue-1
var suffix = y % 2 == 0 ? 0 : 1;
messageSenders[y] = _messageSenderFactory.GetMessageSender($"test-queue-{suffix}");
});
}
// execute
await Task.WhenAll(tasks);
// test
foreach (var ms in messageSenders)
{
Assert.NotNull(ms);
}
// each message sender is for the same queue
var groupedByPath = messageSenders.GroupBy(x => x.Path);
Assert.Equal(2, groupedByPath.Count());
// check all even senders are the same object
var evenSenders = messageSenders.Where(s => s.Path.Equals(queueName0)).ToList();
var evenSender0 = evenSenders[0];
Assert.True(object.ReferenceEquals(evenSender0, evenSenders[1]));
Assert.True(object.ReferenceEquals(evenSender0, evenSenders[2]));
// check all odd senders are the same object
var oddSenders = messageSenders.Where(s => s.Path.Equals(queueName1)).ToList();
var oddSender0 = oddSenders[0];
Assert.True(object.ReferenceEquals(oddSender0, oddSenders[1]));
Assert.True(object.ReferenceEquals(oddSender0, oddSenders[2]));
// check odd and even senders are different objects
Assert.False(object.ReferenceEquals(evenSender0, oddSender0));
}