Script to evaluate the percentage of the size of a pattern in the JavaScript files of a given url

sizeOfStringInUrl.sh

#!/usr/bin/env bash
set -eu -o pipefail
# Script expects these binaries to be present:
# - wget
# - node
# Tested on Mac.

# Example:
#
#   bash sizeOfStringInUrl.sh nextjs.org "\bcreateElement\b"

main() {
  url="$1"
  pattern="${2:-\bcreateElement\b}"

  if [ -e "$url" ]; then
    echo ">> Directory $url already exists... EXITING"
    exit 1
  fi

  echo ">> Downloading $url"
  mkdir "$url"

  cd "$url"
  wget -pk "$url"

  count_occurrences=$(find . -name "*.js" -exec grep -o createElement {} \; | wc -l)
  echo ">> Number of occurrences of \"$pattern\": $count_occurrences"

  total_size_occurrences_with_newlines=$(find . -name "*.js" -exec grep -o createElement {} \; | wc -c)
  total_size_occurrences=$(node -pe "$total_size_occurrences_with_newlines - $count_occurrences")
  echo ">> Total size of occurrences in characters \"$pattern\": $total_size_occurrences"
  echo ">> Assuming 1 character == 1 byte"

  total_size_of_js_files_in_bytes=$(\
    find . -iname "*.js" | \
    xargs stat -f%z | \
    awk '{ s+=$1 } END { print s }'\
  )
  echo ">> Total size of the JavaScript files in bytes: $total_size_of_js_files_in_bytes"

  percentage=$(node -pe "100.0 * $total_size_occurrences / $total_size_of_js_files_in_bytes")
  echo ">> Percentage size of \"$pattern\" in \"$url\": ${percentage}%"
}

main "$@"