find-node-or-install

Finds the bin directory where node, npm and npx are installed. Or if not found, installs a local copy of them in a temp folder, then outputs where they are.

If no Node.js installation is found, the script makes use of nvm, configuring it to install the latest Node.js LTS version in a temporary directory.

Prerequisites

curl or wget; and
tar or unzip or git

Installation

curl -o find-node-or-install \
  https://raw.githubusercontent.com/hugojosefson/find-node-or-install/master/find-node-or-install
  
chmod +x find-node-or-install

Choose Node.js version

If you want, you can change the version of Node.js to be installed. Do it by setting the NODE_VERSION env variable. Default is --lts.

Example:

NODE_VERSION=12 ./find-node-or-install

Usage from command-line

export PATH="$(./find-node-or-install):$PATH"

Usage from Makefile

Put this at the top of your Makefile:

SHELL := /bin/sh
NODE_PATH = $(shell ./find-node-or-install)
PATH := $(NODE_PATH):$(shell echo $$PATH)

All of this enables you to use any npm module in an environment where you don't have to make assumptions about Node.js/npm availability.

Optional executables

There are also some executables+symlinks available here. They can be used to launch node, npm, npx or yarn via find-or-install-node.

Examples

Shebang in single .js file

If you put these comments at the top of a .js file, you can make it self-contained and executable:

#!/bin/sh
/* 2>/dev/null
url=https://raw.githubusercontent.com/hugojosefson/find-node-or-install/master/find-node-or-install
PATH="$( (curl -s $url||wget -qO- $url) 2>/dev/null|sh 2>/dev/null):$PATH"
exec node "$0" "$@"
*/

console.log('Hello from inside a self-contained, *magically* executable .js file!')

Downloaded offline

To keep find-node-or-install downloaded and offline:

curl -o find-node-or-install \
  https://raw.githubusercontent.com/hugojosefson/find-node-or-install/master/find-node-or-install 

curl -o node \
  https://raw.githubusercontent.com/hugojosefson/find-node-or-install/master/node 

chmod +x find-node-or-install node
ln -s node npm
ln -s node npx
ln -s node yarn

Then in a hello.js file which you want to execute, in the same directory:

#!./node
console.log('Hello from inside an executable .js file!');

Make it executable, and run it:

chmod +x hello.js
./hello.js

=> Hello from inside an executable .js file!

License

MIT