How do I get environmment process.NODE_ENV=development in server.ts in angular 6 universal - variables

Question

app.listen(PORT, () => {
console.log("process.env.NODE_ENV", process.env.NODE_ENV);
console.log(`Node server listening on http://localhost:${PORT}`);
});
i am getting process.env.NODE_ENV 'none' in console
command for build
npm run build:alpha:ssr NODE_ENV=alpha
my package.json file
{
"name": "mobilesite-ecommerce",
"version": "0.0.0",
"license": "MIT",
"scripts": {
"ng": "ng",
"start": "ng serve -c local",
"build": "ng build",
"test": "ng test",
"lint": "ng lint",
"e2e": "ng e2e",
"build:ssr": "npm run build:client-and-server-bundles && npm run webpack:server",
"serve:ssr": "node dist/server",
"build:client-and-server-bundles": "ng build --prod --deploy-url=##scripturl## && ng run mobilesite-ecommerce:server:production",
"webpack:server": "webpack --config webpack.server.config.js --progress --colors",
"build:prerender": "npm run build:client-and-server-bundles && npm run webpack:server && npm run generate:prerender",
"generate:prerender": "cd dist && node prerender",
"serve:prerender": "cd dist/browser && http-server",
"build:local:ssr": "npm run build:local:client-and-server-bundles && npm run webpack:local:server",
"serve:local:ssr": "node dist/server",
"build:local:client-and-server-bundles": "ng build -c local && ng run mobilesite-ecommerce:server:local",
"webpack:local:server": "webpack --config webpack.server.config.js --progress --colors",
"build:development:ssr": "npm run build:development:client-and-server-bundles && npm run webpack:development:server",
"serve:development:ssr": "node dist/server",
"build:development:client-and-server-bundles": "ng build -c development && ng run mobilesite-ecommerce:server:development",
"webpack:development:server": "webpack --config webpack.server.config.js --progress --colors",
"build:alpha:ssr": "npm run build:alpha:client-and-server-bundles && npm run webpack:alpha:server",
"serve:alpha:ssr": "node dist/server",
"build:alpha:client-and-server-bundles": "ng build --prod -c alpha --deploy-url=##scripturl## && ng run mobilesite-ecommerce:server:alpha",
"webpack:alpha:server": "webpack --config webpack.server.config.js --progress --colors"
},
"private": true,
"dependencies": {
"#angular/animations": "^6.0.6",
"#angular/common": "6.0.6",
"#angular/compiler": "6.0.6",
"#angular/core": "6.0.6",
"#angular/forms": "6.0.6",
"#angular/http": "6.0.6",
"#angular/platform-browser": "6.0.6",
"#angular/platform-browser-dynamic": "6.0.6",
"#angular/platform-server": "^6.0.6",
"#angular/router": "6.0.6",
"#angular/service-worker": "6.0.6",
"#fortawesome/fontawesome-svg-core": "^1.2.0-11",
"#fortawesome/free-brands-svg-icons": "^5.1.0-11",
"#fortawesome/free-solid-svg-icons": "^5.1.0-11",
"#ng-bootstrap/ng-bootstrap": "^2.1.1",
"#nguniversal/common": "^6.0.0",
"#nguniversal/express-engine": "^6.0.0",
"#nguniversal/module-map-ngfactory-loader": "^6.0.0",
"#ngx-share/core": "^6.0.1",
"angular-6-social-login": "^1.1.1",
"bootstrap": "^4.1.1",
"compression": "^1.7.3",
"core-js": "^2.4.1",
"font-awesome": "^4.7.0",
"hiredis": "^0.5.0",
"localstorage-polyfill": "^1.0.1",
"mock-browser": "^0.92.14",
"ng-lazyload-image": "^4.0.0",
"ngx-swiper-wrapper": "^6.3.0",
"node-sass": "^4.7.2",
"redis": "^2.8.0",
"redis-server": "^1.2.2",
"rxjs": "^6.2.1",
"sourcebuster": "^1.1.0",
"ts-loader": "^4.4.1",
"webpack-cli": "^3.0.8",
"zone.js": "^0.8.26"
},
"devDependencies": {
"#angular-devkit/build-angular": "~0.6.8",
"#angular/cli": "^6.0.8",
"#angular/compiler-cli": "6.0.6",
"#angular/language-service": "6.0.6",
"#types/jasmine": "~2.5.53",
"#types/jasminewd2": "~2.0.2",
"#types/node": "~6.0.60",
"#types/youtube": "0.0.31",
"codelyzer": "^4.0.1",
"express": "^4.16.3",
"http-server": "^0.11.1",
"jasmine-core": "~2.6.2",
"jasmine-spec-reporter": "~4.1.0",
"karma": "~1.7.0",
"karma-chrome-launcher": "~2.1.1",
"karma-cli": "~1.0.1",
"karma-coverage-istanbul-reporter": "^1.2.1",
"karma-jasmine": "~1.1.0",
"karma-jasmine-html-reporter": "^0.2.2",
"protractor": "~5.1.2",
"ts-node": "~3.2.0",
"tslint": "~5.7.0",
"typescript": "2.7.2"
}
}

Answer 1

There is a plugin for webpack that allows you to define environment variables.
I added this into my plugins in webpack.server.config.ts and it fixed the issue for me:
module.exports = {
...
plugins: [
new webpack.EnvironmentPlugin(['NODE_ENV'])
],
...
};
Documentation Reference:
https://webpack.js.org/plugins/environment-plugin/

Answer 2

webpack = require("webpack");
env = process.env.NODE_ENV || 'none';
module.exports = { plugins: [ new webpack.DefinePlugin({ "process.env.NODE_ENV": JSON.stringify(env) }) ] };
NODE_ENV=alpha npm run build:alpha:ssr

Answer 3

you need to set environnement variables before the command:
NODE_ENV=alpha npm run build:alpha:ssr