heatsync

Heatsync

This is a module to watch and reload CommonJS Modules on modification and sync results with objects

In applications which require high uptime and are constantly being worked on as the development process normally is, developers might find it necessary to reload modules and have their changes take effect immediately without restarting the application. Luckily, that's where Heatsync comes in.

Basic Usage

const Heatsync = require("heatsync");
const sync = new Heatsync();

// Heatsync offers native-like module resolution, but without types for fs struct.
// relative paths based on the file the function is being called will work.
// absolute paths also work.
const utils = sync.require("./utils.js");

// The require method also accepts an Array of IDs where IDs can be:
// A relative path, an absolute path or a node_module name.
const [file1, file2, file3] = sync.require([
	"./epic.js",
	"./poggers.js",
	"../lib/controller.js"
]);

How it works

Object.assign and the delete keyword mutates the state of an Object. which means it doesn't replace the reference. You can assign values to an Object through Object.assign and the new/updated properties will appear in other files so long as you have the same reference.

Gachas

You must be very careful with Sync.resync as it iterates over modules and their children recursively and drops the cache for them. If another module references a child mod that gets dropped and it's not being synced by heatsync, then multiple instances of the mod which may be outdated would still be held within memory and possibly wouldn't get swept. With this in mind, practice efficient memory management and if you must use resync, then make sure references would not hold stale copies of a mod.

Examples

Code for an example can be found at example/ Follow along for a better understanding

First, we require scripts/test.js somewhere and call test.process("John Doe"); It will output "John Doe is epic"

But let's say you modify utils.epic to be

function(name) {
	console.log(`${name} 100% is epic`);
}

Since it's required through Heatsync, Heatsync will drop the require cache for the file and then re-require the file, then apply the changes of the file to the reference it returned to you through the require method which means that the changes will be available to you immediately wherever you used Heatsync's require method to require said file. Subsequent calls of the function from the example with the same arguments will now write "John Doe 100% is epic" to the console.