barakedry / modules-middleware

express middleware for serving npm modules to client side

modules-middleware

Express middleware for serving node modules to client side.
Useful for serving client side apps structued as node module package, containing a package.json and dependencies.

modules-middleware:

• Serves sources and static assets from the module directory
• Serves sources and static assets of module dependencies defined in package.json (resolves using node's require.resolve starting from the module directory)
• works with monorepos
• transforms package names to valid browser ES6 paths when serving .js, .jsm and .html source files of the module and dependencies. for example, a js module containing an ES6 import such as:
  import { PolymerElement } from '@polymer/polymer'; will transform into
  import { PolymerElement } from '/node_modules/@polymer/polymer/';
  • Support node.js require() flexibility, (omitting .js extension, specifying directory name only to serve a contained index.js file, etc..)
  • Multiple packages sharing the same dependency at the same version will result in the same client url (for caching)
  • Multiple packages sharing the same dependency with different versions will result in a different client url

Install

$ npm install modules-middleware

or

$ yarn add modules-middleware

API

var modulesMiddleware = require('modules-middleware')

modulesMiddleware(modulePath, options)

Create a new middleware function to serve files from within a given module path.

Options

modulesDirectoryUrlName

The prefix of packages urls for transformed client side sources, defaults to "node_modules".

Serving using express

This is a simple example of using Express.

var express = require('express')
var modulesMiddleware = require('modules-middleware')

var app = express()

app.use(modulesMiddleware('./frontend'));
app.listen(3000)

with monorepo

if you are using a monorepo containing a package of your client side code you may use require.resolve as the module path

var express = require('express')
var modulesMiddleware = require('modules-middleware')

var app = express()

app.use(modulesMiddleware(require.resolve('my-client-app'));
app.listen(3000)

License

MIT