NPM and NodeJS Compatibility: NodeJS works from PM prompt, but not script - node.js

Question

I am attempting to get a lighthouse script running in Node.JS (which I am new to). I followed the intial instructions here https://github.com/GoogleChrome/lighthouse/blob/master/docs/readme.md#using-programmatically. I was able to complete the prior steps in the package manager console (Visual Studio 2017):
npm install -g lighthouse
lighthouse https://airhorner.com/
//and
lighthouse https://airhorner.com/ --output=json --output-path=./report/test1.json
However, I do get an initial warning that NPM only supports Node.JS in versions 4 through 8 and recommends a newer version. The problem is I am running Node v12 and NPM v5 - both the latest.
When I create a script version like below (app.js)
const lighthouse = require('lighthouse');
const chromeLauncher = require('chrome-launcher');
const config = {
extends: 'lighthouse:default',
settings: {
emulatedFormFactor: 'desktop',
onlyCategories: 'performance',
output: 'json',
outputPath: './report.json'
}
};
function launchChromeAndRunLighthouse(url, opts = null, config) {
return chromeLauncher.launch().then(chrome => {
opts.port = chrome.port;
return lighthouse(url, opts, config).then(results => {
return chrome.kill().then(() => results.lhr);
});
});
}
// Usage:
launchChromeAndRunLighthouse('https://airhorner.com/', config).then(results => {
// Use results!
});
And run the command
C:\src\project> node app.js
I get the error - Cannot find module 'lighthouse'

Answer 1

don't install lighthouse locally use it inside your working dir .
first start by running npm init that will create the package.json file inside the current working dir
then npm install --save lighthouse will download it and save it to node_modules now you can use it locally inside your working dir
it should look something like this
app.js
package.json
node_modules/
then run node app.js