How to detect when `prepublish` script is executed as a result of running `npm install` - node.js

Question

https://docs.npmjs.com/misc/scripts
prepublish: Run BEFORE the package is published. (Also run on local npm install without any arguments.)
I want my script to execute only in case of user executing npm publish. However, NPM will execute "prepublish" script if user runs "npm install".

Answer 1

The only way I have figured out is using NPM internal ENV variables:
// NPM will run prepublish script after `npm install` (https://docs.npmjs.com/misc/scripts)
// This ensures that when script is executed using `npm *` it is run only when the command is `npm publish`.
if (process.env.npm_config_argv) {
let npmConfigArgv;
npmConfigArgv = JSON.parse(process.env.npm_config_argv);
if (npmConfigArgv.original[0] !== 'publish') {
console.log('`bundle-dependencies prepublish` will not execute. It appears that `prepublish` script has been run by `npm install`.');
return;
}
}
It appears that NPM stores the original command in process.env.npm_config_argv variable.
In case you are wondering, each NPM script is being run in different process. Therefore, something like setting a custom ENV variable in preinstall script does not work.

Answer 2

Another solution that's also worked for me (again from this thread) is using a prepublish.sh script like the following:
get_json_val() {
python -c "import json,sys;sys.stdout.write(json.dumps(json.load(sys.stdin)$1))";
}
get_npm_command() {
local temp=$(echo $npm_config_argv | get_json_val "['original'][0]")
echo "$temp" | tr -dc "[:alnum:]"
}
if [ $(get_npm_command) != "publish" ]; then
echo "Skipping prepublish script"
exit 0
fi
# else
echo "prepublish called"
# prepublish logic follows:
# ...
So if your package.json file is:
{
"name": "foo",
"version": "0.0.1",
"description": "",
"main": "lib/foo.js",
"scripts": {
"prepublish": "./prepublish.sh"
},
"dependencies": {
"lodash": "^4.10.0"
}
}
… then running npm install will only install the dependencies and the prepublish target will only be called when user types npm run publish.
Yet another way is to use the in-publish package (again mentioned in this thread). Place it in your development dependencies and then in your package.json have something like:
"prepublish": "(in-publish && npm run clean && flow check && npm run test && npm run build) || not-in-publish"

Answer 3

As of npm#4.0.0, the prepublish script is now deprecated. To run a script on both npm publish, and npm install without arguments (the bahaviour of prepublish), you should use prepare instead.
To run a script only on npm publish, you should use prepublishOnly.