twitter-actual-follower.sh

#!/bin/env bash

if [[ $# == 0 ]]; then
  echo "Usage: ./twitter-actual-follower.sh (screen_name)" >&2
  echo "twurl is required. " >&2
  exit 1
fi

echo "Fetching data... (It may take some time. )" >&2

cursor="-1"
friendsCounts=""

while :; do
  followersList="$(twurl "/1.1/followers/list.json?count=200&cursor=$cursor&include_user_entities=false&screen_name=$1")"
  # For rate limit
  sleep 60

  if [[ $(echo "$followersList" | jq ".errors | length") != 0 ]]; then
    echo "$followersList" >&2
    exit 1
  fi

  friendsCounts="$friendsCounts$(echo "$followersList" | jq ".users[].friends_count")
"

  cursor="$(echo "$followersList" | jq -r ".next_cursor_str")"

  if [[ "$cursor" == "0" ]]; then
    break
  fi
done

# Remove new-line at the end
friendsCounts=$(echo "$friendsCounts" | head -c -1)

echo "$friendsCounts" | awk '{actualFollower += 1/$1} END {print actualFollower}'