check_http_server.rb.erb

#!/usr/bin/env ruby

def check_server(url)
    @output = %x(httping -c 1 -s -l -m #{url}).split()
    return @output[-1].to_i
end

server_url = '<%= @start_page %>'
lock_file = '/tmp/check_http_lock'

# Exit if loop is running.
exit if File.exist?(lock_file)

status = check_server(server_url)

if status == 200
    exit 0
else
    File.new(lock_file, "w")
    system("DISPLAY=:0 zenity --info --text='Site down.  Please stand by.' &")
    until status == 200
       status = check_server(server_url)
       sleep 5
    end
    system('pkill zenity')
    system('logger -t check_http_server.rb "server down - restarting graphical-eol-display.service"')
    system('systemctl restart graphical-eol-display.service')
    File.delete(lock_file)
    exit 0
end