Removing npm tmp after install

npm-tmp-clean.sh

#!/usr/bin/env bash

# this is pid of the bash we are in
bash_pid=$$
bash_pid=$(echo -e ${bash_pid} | tr -d '[[:space:]]');

# this is shell of the bash
shell_pid=$(ps -p ${bash_pid} -o ppid=;)
shell_pid=$(echo -e ${shell_pid} | tr -d '[[:space:]]');

# this is the npm who runs shell
npm_pid=$(ps -p ${shell_pid} -o ppid=;)
npm_pid=$(echo -e ${npm_pid} | tr -d '[[:space:]]');

# test whether npm tmp configuration is set
# if not, assume the default /tmp
if [ -z ${npm_config_tmp} ]; then 
	  npm_config_tmp=/tmp
fi;

echo "Removing ${npm_config_tmp}/npm-${npm_pid}*";
rm -rf "${npm_config_tmp}"/npm-${npm_pid}*

so-much-fun.sh

#!/usr/bin/env bash

npm install -g json
curl -O https://gist.githubusercontent.com/contolini/c79fa8b193625cfeb826632299feb440/raw/263d9955d4d0ba77cba260b713e1918dfcab06e3/npm-tmp-clean.sh
chmod +x npm-tmp-clean.sh
json -I -f ./package.json -e 'this.scripts.postinstall="./npm-tmp-clean.sh"'