something important about Websocket handshaking

sec_websocket_key_rule.rb

require 'digest/sha1'
require 'base64'

# client request
  # GET / HTTP/1.1
  # Upgrade: websocket
  # Connection: Upgrade
  # Host: example.com
  # Origin: null
  # Sec-WebSocket-Key: sN9cRrP/n9NdMgdcy2VJFQ==
  # Sec-WebSocket-Version: 13

# server response
  # HTTP/1.1 101 Switching Protocols
  # Upgrade: websocket
  # Connection: Upgrade
  # Sec-WebSocket-Accept: fFBooB7FAkLlXgRSz0BT3v4hq5s=
  # Sec-WebSocket-Origin: null
  # Sec-WebSocket-Location: ws://example.com/

sec_websoekct_key = 'sN9cRrP/n9NdMgdcy2VJFQ=='

p "sec_websoekct_key is #{sec_websoekct_key}"

token = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'

# Digest::SHA1.base64digest(sec_websoekct_key + token)

# NOTICE!! hexdigest is invalid.
encrypted = Digest::SHA1.digest(sec_websoekct_key + token)

sec_websokect_accept = Base64.encode64(encrypted).strip

p "generated sec_websokect_accept is #{sec_websokect_accept}"