find all required packages in a directory

findrequire.sh

#!/bin/bash
# find all required packages in a directory
# usage
#   findrequire src
#   findrequire src | xargs npm i -S
#   findrequire test | xargs npm i -D
find $1 -iname "*.js" |\
  xargs egrep -h "require\(['][^.]" |\
  sed "s/.*require('\([^'']*\)').*/\1/g" |\
  egrep -v "^(assert|child|cluster|events|dgram|dns|domain|fs|http|https|inspector|net|os|path|punnycode|querystring|readline|stream|string_decoder|tls|tty|udp4|url|util|v8|vm|zlib)$" |\
  sort -u