esbuild-live-reload VS chokidar

Today we created an esbuild config file that enables live reloading (but not HMR) for our jsbundling-rails powered Rails application. As I mentioned at the beginning of this article, this is very much an experiment and this configuration has not been tested on an application of any meaningful size. You can find the finished code for this example application on Github.

For this, we'll use chokidar - more specifically the chokidar-cli package. chokidar is probably the most useful file watching library for the nodejs ecosystem and it will serve us well.

tailwindcss -> chokidar -> braces -> fill-range -> to-regex-range -> is-number

is-number was first published 9 years ago, when these kind of micro-packages were in vogue. braces was added as a dependency to chokidar over 6 years ago [1]. And if it ain't broke, don't fix it. I don't think the average JS dev today is going out and pulling in these deps.

[1] https://github.com/paulmillr/chokidar/commit/cbdf25563cfff7f...

The watching magic is really in the https://www.npmjs.com/package/chokidar library

> It’s typical to listen to this stream of events and use chained if-else statements to determine an action based on the type of the events that occur.

You'd think something like directory watching would have a clear set of events that would make nice objects with consistent meanings, but in my experience file watching gets crazy complicated, and can have all sorts of edge cases.

Just take a looked here for all the various edge cases that crop up: https://github.com/paulmillr/chokidar/issues

Then you have linux, windows, macos, and maybe you want to abstract over some underlying implementation like chokidar vs fb/watchman vs webpack/watchpack. Every new OS release could also cause things to change.

So usually its going to be a bunch of if-else statements hacked together to get around edge cases, and have to be revisited later on.

Any attempt to abstract this into objects, just obfuscates things. And OO forces you to name things, when in fact they might be un-nameable. `FileSystemModifyEventExceptWhenXAndYAndSometimesZ`.

The behavior might rely on a series of events together, so the object hierarchy must be re-worked.

OO has this rosy idea that we just have to come up with the perfect hierarchy, but things change in unexpected ways, and everything must have a descriptive noun.

Next, you can use a library like chokidar to listen for changes in your source directory. Create a ws server, and whenever a file changes, send a message.

As another has mentioned, nodemon uses chokidar under the hood for the actual file watching part.

At the end of the day, ironically, Nodemon does not even implement file watching functionality. It is a thin wrapper around chokidar (see source code), and the way it is being used is neither efficient (CPU and your battery usage) or performant. So it is not a false argument, just perhaps not the most appealing.

for file watching, it might use something similar to https://www.npmjs.com/package/chokidar

First, we need to install chokidar to enable watching and automatically refreshing our files.