@foadonis/autoloader

NodeJS module autoloader with HMR support

Getting Started

npm install @foadonis/autoloader

This library provides a way to autoload files that matches a specific pattern. It integrates nicely with hot-hook to support Hot Module Reloading.

Example

In the following example we autoload all modules that matches app/graphql/resolvers/**/*_resolver.(ts|tsx|js|jsx) to register them inside our GraphQL server.

Once the GraphQL server started we start watching for added, reloaded and removed modules.

import { Autoloader } from '@foadonis/autoloader'

const server = new GraphQLServer()

const autoloader = new Autoloader({
  path: new URL('app/graphql/resolvers', app.appRoot),
  glob: '**/*_resolver.(ts|tsx|js|jsx)',
})

// Initial auto-loading
for await (const [path, module] of autoloader.autoload()) {
  server.resolvers.set(path, module)
}

// Starts the server with the initial GraphQL resolvers
await server.start()

// In development start watching for changes
if (isDevelopment) {
  autoloader.hooks.add('loaded', (path, module) => {
    server.resolvers.set(path, module)
    server.reload()
  })

  autoloader.hooks.add('unlink', (path, module) => {
    server.resolvers.delete(path)
    server.reload()
  })

  await autoload.watch()
}

Autoloader.autoload()

The autoload() method loads discovered modules that matches the provided glob pattern. Additionally, if hot-hook has been initialized it listens for module disposal and reload it.

import { Autoloader } from '@foadonis/autoloader'

const autoloader = new Autoloader({
  path: new URL('app/controllers', app.appRoot),
  glob: '*_controller.(js|ts|jsx|tsx)',
})

for await (const [path, module] of autoloader.autoload()) {
  // Loaded module
}

autoloader.hooks.add('loaded', (path: string, module: any) => {
  // A module has been reloaded
})

Autoloader.watch()

The watch() method watches for added and removed files. Added files are automatically loaded and plugged to hot-hook if available.

Note that the watcher does not autoload modules that are part of the initial scan (see Autoloader.autoload()). In most cases you want to first run autoload() and then start the watcher.

import { Autoloader } from '@foadonis/autoloader'

const autoloader = new Autoloader({
  path: new URL('app/controllers', app.appRoot),
  glob: '*_controller.(js|ts|jsx|tsx)',
})

autoloader.hooks.add('loaded', (path: string, module: any) => {
  // module has been loaded (added or reloaded)
})

autoloader.hooks.add('unlink', (path: string) => {
  // unload the module from router
})

await autoloader.watch()

License

MIT licensed.