Webpack and Express - Critical Dependencies Warning - express

Question

I have the following webpack.config.ts:
var webpack = require( 'webpack' );
var path = require( 'path' );
module.exports = {
entry: [
'./api/bin/www.ts'
],
output: {
path: path.resolve( __dirname, './dist/api' ),
filename: 'index.js'
},
module: {
loaders: [
{ test: /\.ts$/, loader: 'awesome-typescript-loader' },
{ test: /\.json$/, loader: 'json-loader' }
]
},
resolve: {
extensions: [ '', '.js', '.ts' ]
},
target: 'node',
node: {
console: true,
fs: 'empty',
net: 'empty',
tls: 'empty'
}
};
When I run webpack I get a warning about a dependency:
WARNING in ./~/express/lib/view.js
Critical dependencies:
78:29-56 the request of a dependency is an expression
# ./~/express/lib/view.js 78:29-56
The express server I start with this is no more than a Hello World example and functions as should but I am concerned about this warning.
My googlefu hasn't revealed any passable solutions. I have seen one particular instance of this problem but the solutions were to bypass the warning by not showing it.

Answer 1

Use webpack-node-externals.
const nodeExternals = require('webpack-node-externals');
{
target: 'node',
externals: [nodeExternals()],
}
https://www.npmjs.com/package/webpack-node-externals

Answer 2

For those that only need to remove the express due to the view lib as mentioned here you can also explicitly target express in externals from your webpack config.
externals: [{ 'express': { commonjs: 'express' } }]

Answer 3

My warning only got fixed with:
module.exports =
{
target: 'node',
externals: {
"express": "require('express')"
}
}

Answer 4

Instead of excluding all of the npm dependencies to be bundled with nodeExternals you can also exclude only express by natively requiring it by replacing
import express from 'express';
// Or
const express = require('express');
To
const express = __non_webpack_require__('express');
That will suppress the warning caused by express