macOS Automator Action to calculate file hashes

applescript.scpt

on run {input, parameters}
      with timeout of 360 seconds
        tell application "System Events"
          activate
          display dialog input buttons {"OK"} default button 1 with title "File Hashes" giving up after 300 --seconds
        end tell
      end timeout
    end run

calculate.sh

for file; do
      if [[ -d "$file" ]]; then
        echo "$(basename "$file") is a directory"
      else
        cd "$(dirname "$file")"
        printf "File: $(basename "$file")"

        printf "\n\nMD5: "
        /usr/bin/openssl md5 "$(basename "$file")" | egrep -o [a-f0-9]{32}

        printf "\nSHA1: "
        shasum -a 1 "$(basename "$file")" | egrep -o [a-f0-9]{40}

        printf "\nSHA256: "
        shasum -a 256 "$(basename "$file")" | egrep -o [a-f0-9]{64}
      fi
    done | tr "\n" "\r"

Working from the quite perfect code sample on Superuser I made an Automator service to display the MD5, SHA1 and SHA256 hashes for a file via the Services context menu.

Instructions:

• Make new Automator service
• Set to "Service receives selected files or folders in Finder.app
• Run Shell Script calculate.sh
• Run Applescript applescript.scpt