@epic-web/remember

🤔 @epic-web/remember

Simple, type-safe, "singleton" implementation.

For when your "hot module replacement" involves re-evaluating a module, but you don't want to actually re-evaluate a portion of it.

npm install @epic-web/remember

The problem

You're using a framework like Remix with --manual mode and re-evaluating your modules on every change. But you have some state that you don't want to lose between changes. For example:

• Database connections
• In-memory caches

This solution

This was copy/paste/modified/tested from @jenseng's abuse-the-platform demo (ISC). It's basically a type-safe singleton implementation that you can use to keep state between module re-evaluations.

Usage

import { remember } from '@epic-web/remember'

export const prisma = remember('prisma', () => new PrismaClient())

Keep in mind that any changes you make within that callback will not be reflected when the module is re-evaluated (that's the whole point). So if you need to change the callback, then you'll need to restart your server.

Forget a value

It might be required to explicitly forget a value if it gets outdated, a memorized connection gets lost or memorized instance closes/errors/etc.

import { remember, forget } from '@epic-web/remember'

export const server = remember('server', () =>
    http.createServer().listen('8080')
        .on('close', () => forget('server')))

License

MIT

Credit

The original code was written by @jenseng and then I modified it and published it to fit my needs.