Get client ips of redis connection.

redis_client_ip.rb

#!/usr/bin/env ruby

# Usage
#
#   echo 'client list' | redis-cli -h $HOST -p $PORT | ./redis_client_ip.rb
# 
# Reference
#
#   http://www.jstorimer.com/blogs/workingwithcode/7766125-writing-ruby-scripts-that-respect-pipelines
#   http://redis.io/commands/client-list

require 'set'
ips = Set.new

while input = ARGF.gets
  input.each_line do |line|
    # id=203767 addr=[::1]:1234 fd=921 name= age=9791 idle=348 flags=N db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=0 obl=0 oll=0 omem=0 events=r cmd=exec
    # id=203604 addr=10.0.0.1:1234 fd=364 name= age=22830 idle=1399 flags=N db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=0 obl=0 oll=0 omem=0 events=r cmd=exec

    addr = line.split[1].split('=')[1]
    next if addr.start_with?('[')

    ip = addr.split(':')[0]
    ips << ip
  end
end

p ips