Define a first-in-first-out queue: items are added to the back (enqueue) and taken from the front (dequeue). This is the shape which si-funciona's queueManager / queueTimeout expect of a queue.
Take the item from the front of the queue.
The item, or null when the queue is empty
Check whether the queue has no items.
Add an item to the back of the queue.
The item to add
Look at the item at the front of the queue, without removing it.
Count the items in the queue.
Define a first-in-first-out queue: items are added to the back (enqueue) and taken from the front (dequeue). This is the shape which si-funciona's queueManager / queueTimeout expect of a queue.