TaskQueue | A Task Queue Class developed in Swift

Your understanding is quite correct, and you are right that setTimeout(fn, 0) may not always fire after a "related" event: it is indeed very possible that these events are fired from two different tasks, very unlikely they'll use the timer task sources, and you correctly identified the bit that would make the event loop "possibly" select a task from an other task source.

However in this exact case, you are safe.

The submit event and the formdata one are fired from the same "task"*.

If you look at the form submit algorithm, you can see that the submit event is directly fired at step 6.5, instead of being wrapped in a task that would get queued like it's often the case.

Let shouldContinue be the result of firing an event named submit at form [...]

Then in the same algorithm, without any in parallel or anything implying asynchronicity, we have the step 8 that says

Let entry list be the result of constructing the entry list with form, submitter, and encoding.

And in this constructing the entry list algorithm, at the step 7, we have the call to

Fire an event named formdata at form [...]

once again without any asynchronicity allowed.

So we can be sure that these events will fire without anything else in between (apart microtasks), and that your timer callback from the submit event will fire after the formdata callback, even two requestAnimationFrame callbacks scheduled in the same frame (that are also "synchronous" for the event loop) won't be able to interleave there:

I'd recommend using select! instead of interruptible futures to detect one of 3 conditions in your loop:

• download task is finished
• the data is outdated signal
• data expired timeout signal

"The data is outdated" signal can be conveyed using a dedicated channel.

select! allows waiting for futures (like downloading and timeouts), and reading from channels at the same time. See the tutorial for examples of that.

Solution sketch:

I'd like to know by what criteria implementors run? How do they evaluate the "important-ness" of queues?

That's basically their call, a design choice made from years of experience looking at how their tool is being used and what should be prioritized (and also probably a good part of common sense).

The WHATWG indeed doesn't define at all how this task prioritization should be implemented. All they do is to define various task-sources (not even task-queues), to ensure that two tasks queued in the same source will get executed in the correct order.

The closest we have of defining some sort of prioritization is the incoming Prioritized Task Scheduling API which will give us, web-authors, the mean to post prioritized tasks, with three priority levels: "user-blocking", "user-visible" and "background".

To check what browsers actually implement, you'd have to go through their source-code and inspect it thoroughly.
I myself already spent a couple hours in there and all I can tell you about it is that you better be motivated if you want to get the full picture.
A few points that may interest you:

• All browsers don't expose the same behavior at all.
• In Chrome, setTimeout() still has a minimum delay of 1ms (https://crbug.com/402694)
• In Firefox, because Chrome's 1ms delay was producing different results on some web-pages, they create a special very-low-priority task-queue only for the timers scheduled before the page load, the ones scheduled after are queued in a normal priority task-queue. (https://bugzil.la/1270059)
• At least in Chrome, each task-queue has a "starvation" protection, which prevents said queue to flood the event-loop with its own task, by letting the queues with lower priority also execute some of their tasks, after some time (not sure how much).

And in the end I'd like to see an example that shows the order of these queues, if it is possible.

As hinted before, that's quite complicated, since there is no "one" order.

Your own example though is quite a good test, which in my Chrome browser does show correctly that the UI task-queue has an higher priority than the timer one (the while loop takes care of the 1ms minimum delay I talked about). But for the DOMContentLoaded though, I must admit I'm not entirely sure it shows anything significant: The HTML parser is also blocked by the while loop and thus the task to fire the event will only get posted after the whole script is executed.

But given this task is posted on the DOM Manipulation task source, we can check it's priority by forcing a other task that uses this task source, e.g script.onerror.
So here is an update to your snippet, with a few more task sources, called in reverse order of what my Chrome's prioritization seems to be:

Twilio developer evangelist here.

The structure of your form and the data within it seem relatively arbitrary. I know it is based on whatever data that you get from the TaskRouter API, which will likely not change, but you do still have to render lists of form items. To that end I wrote up a quick experiment to see how you could solve this for any object that you can give a component. Hopefully this is helpful and you can apply it to your application.

React's model is that data is sent down and actions bubble up, so in this case you want to store your form's state in the top level component, which also handles the form's submit event, and send that state down to the child components. The child components should then send up change events that update the state.

Then, when the form is submitted, you can send the full state to the endpoint (side note here, we recommend that you implement calls to the Twilio API on the server side, not in the client, so that you don't embed your API credentials in the front-end where they can be taken). I note that your application doesn't currently have a

The previous paragraph is the easy part, the harder part is keeping the state up to date. If you run your code as you have it, where a number of the inputs have a value attribute but not an onChange handler, you'll find React telling you that you need to do something about it.

So, you need to implement an onChange handler that updates the state in the top level component. I had a go at implementing this myself, for an arbitrary object full of data. I created a handleUpdate function that could be passed to any input as an onChange handler. When the handleUpdate function is triggered, it is passed an event which points to the DOM element that triggered it. You can use this to get the value of the element to update your state:

This is usually done by specifying a shard parameter for each task and reusing the same queue. As noted in your example, the entire java object is serialized with DeferredTask. So you can simply pass in any values you want in a constructor. E.g.

Yes, the JMS consumers are polling. By default Camel uses Spring's DefaultMessageListenerContainer under the hood.

The Spring-Listener itself uses the JMS API directly.

Spring uses a default timeout of 1 second to pull messages. I don't know if you really can change this with Camel's receiveTimeout option.

I'm not sure but i think you dont can route traffic from the host to containers on mac osx.

https://docs.docker.com/desktop/mac/networking/

You have explicitly named the task "add_trades_to_database"

The answer lies in what is happening if this code executes while there is nothing in the queue.

var workItem = await TaskQueue.DequeueAsync(stoppingToken);

The answer is that nothing is happening. This line of code doesn't execute over and over again until something is dequeued. That's why there's no need for a delay.

It also doesn't block until something is dequeued.

What happens is that the thread executing the method is freed to do something else. No thread is dedicated to the execution of DequeueAsync. (See this excellent post - There Is No Thread.)

When and if an item appears in the queue to be dequeued, then an available thread is assigned to resume execution of the method.

DequeueAsync only throws an exception if

• the cancellation token is canceled
• the queue's Complete method is called and the queue is empty, which means that you're no longer expecting anything to appear in the queue.