node – underblob

Get package.json version from CLI

Using Node

node -p -e "require('./package.json').version"

The -p argument prints the result and the -e argument expects executable JS to follow it. This one is also helpful for getting specific properties from any JSON file.

Using jq

cat ./package.json | jq '.version'

Use the cat program to read the contents of the file and pipe it to the jq program to parse the JSON.

Lodash in Shell

When both Node and Lodash are installed, they can be executed in shell scripts:

CHEESE="Camembert of Goat"
CAMEL_CHEESE=$(node -p -e "require('lodash').camelCase('${CHEESE}')")
KEBAB_CHEESE=$(node -p -e "require('lodash').kebabCase('${CHEESE}')")
echo $CAMEL_CHEESE # camembertOfGoat
echo $KEBAB_CHEESE # camembert-of-goat

Shell commands with Node

Running CLI Node scripts, capture the return value of a shell command:

const execSync = require('child_process').execSync;
const nodeVer = execSync('node -v', { encoding: 'utf8' });

Shell command reports in the CLI:

const execSync = require('child_process').execSync;
execSync('npm -g ls', { stdio: 'inherit' });

Package Panic

Here are a couple good resources for deciding which NPM packages to use in a project:

Update a NPM Project

Update all the packages in a NPM project to the latest version and sort out Babel dependencies:

npx npm-check-updates --upgradeAll
npx babel-upgrade --write
npm install

Tag: node