| Debouncing Javascript Methods
Debouncing means to coalesce several temporally close signals into one signal. For example, your computer keyboard does this. Every time you hit a key, the contacts actually bounce a few times, causing several signals to be sent to the circuitry. The circuitry determines that the bouncing has ended when no bounces are detected within a certain period (the “detection period”). Since people can’t really type faster than roughly 10 keys per second, any signals happening within 100 msec of each other, for example, are likely part of the same key press. (In practice, you should at least halve this, so about 50 msec for our keyboard example. I have no idea what keyboards really use, by the way. This is just an illustration.)
Whenever I bring up the concept of debouncing, developers try to cast it as just a means of throttling. But that’s not true at all. Throttling is the reduction in rate of a repeating event. Throttling is good for reducing mousemove events to a lesser, manageable rate, for instance.
Debouncing is quite more precise. Debouncing ensures that exactly one signal is sent for an event that may be happening several times — or even several hundreds of times over an extended period. As long as the events are occurring fast enough to happen at least once in every detection period, the signal will not be sent!
Debouncing on the other hand could better detect when the user stopped leaning on the keyboard and had arrived at their destination. It’s certainly not perfect. The user still may overshoot their destination, hesitate, and back-track, causing enough delay for the debounce detection period to expire. However, our tests showed that debouncing did a much better job of reducing XHR requests than throttling.
Ajax Data Transfer Format
JSON has taken the award for the easiest method for transporting data when using Ajax. JSON is great to get data from the server side to the client side. What what about when you need to send data to the server side? Sure you can use JSON then - but the advantage of using JSON is lost.
So I propose using another format for it - UED or URL Encoded Data. Its a very simple concept - and it has been in use for a long time - all I have done is create a function that will encode the data into this format. The basic concept behind this is that the most used data structures can be easily encoded into a URL.
You can create variables, numerical arrays, associative arrays, multi-level arrays etc. using existing syntax. The best part is all the server side languages are capable of handling this format - so no parsing is needed.
ued_encode() will take an array as its argument and return the data encoded in UED format - as a string. You can use that string to send the data via POST or GET in the query part of the URL. |
