Node

generators

npm init

simple and built in

https://docs.npmjs.com/cli/init

https://github.com/npm/init-package-json

npm init <initializer>can be used to set up a new or existing npm package.

initializerin this case is an npm package namedcreate-<initializer>, which will be installed bynpx, and then have its main bin executed -- presumably creating or updatingpackage.jsonand running any other initialization-related operations.

testing locally

using local npm server

https://blog.strapi.io/testing-npm-package-before-releasing-it-using-verdaccio-and-ngrok

npm install -g verdaccio
verdaccio

npm adduser --registry  http://localhost:4873

add to package.json

  "publishConfig": {
    "registry": "http://localhost:4873"
  },

run

npm publish

npm link FTW

with typescript watch. it will auto build and link is still good

"name": "@scope/create-myapp",
"version": "1.0.0",
"description": "starter template for building deliverable apps/libs",
"bin": {
  "create-myapp": "./dist/index.js"
},
"scripts": {
     "watch": "npm run build -- -w"
}

npm run watch
npm link

# from anywhere else use a cli app
create-myapp <args> [options]

shell, exec, execFile, fork

https://zaiste.net/nodejs-child-process-spawn-exec-fork-async-await/

https://nodejs.org/api/child_process.html

exec example

const util = require("util");
const exec = util.promisify(require("child_process").exec);

const getVars = async () => {
  const getVar = async (varName) => {
    const { stdout, stderr } = await exec(
      `zsh -c '. ~/.zshrc; echo $${varName}'`,
    );
    if (stderr) return reject(stderr);
    return stdout.toString().trim();
  };

  const [currentThemeRes, zshCustomRes] = await Promise.all([
    getVar("ZSH_THEME"),
    getVar("ZSH_CUSTOM"),
  ]);
  return [currentThemeRes, zshCustomRes];
};

try {
  const [currentTheme, zshCustom] = await getVars();
  console.log(`vars: ${currenttheme} ${zshCustom}`);
} catch (err) {
  console.log("err: ", err);
}

fs

https://dev.to/mrm8488/from-callbacks-to-fspromises-to-handle-the-file-system-in-nodejs-56p2

nvm

env var

https://medium.com/@maxcbc/mocking-environment-variables-in-node-js-a17a416e127c - mocking

child processes

https://jscomplete.com/learn/node-beyond-basics/child-processes

https://www.freecodecamp.org/news/node-js-child-processes-everything-you-need-to-know-e69498fe970a/