@nx/webpack/src/utils/get-client-environment.js

The Nx Plugin for Webpack contains executors and generators that support building applications using Webpack.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.getClientEnvironment = getClientEnvironment;
function getClientEnvironment(mode) {
    // Grab NODE_ENV and NX_PUBLIC_* environment variables and prepare them to be
    // injected into the application via DefinePlugin in webpack configuration.
    const nxPublicKeyRegex = /^NX_PUBLIC_/i;
    const raw = Object.keys(process.env)
        .filter((key) => nxPublicKeyRegex.test(key))
        .reduce((env, key) => {
        env[key] = process.env[key];
        return env;
    }, 
    // If mode is undefined or is dev or prod then webpack already defines this variable for us.
    !mode || mode === 'development' || mode === 'production'
        ? {}
        : {
            NODE_ENV: process.env.NODE_ENV,
        });
    // Stringify all values so we can feed into webpack DefinePlugin
    const stringified = {
        'process.env': Object.keys(raw).reduce((env, key) => {
            env[key] = JSON.stringify(raw[key]);
            return env;
        }, {}),
    };
    return { stringified };
}