instiki/vendor/rails/railties/lib/commands/process/spinner.rb
2007-01-22 07:43:50 -06:00

57 lines
No EOL
1.9 KiB
Ruby

require 'optparse'
def daemonize #:nodoc:
exit if fork # Parent exits, child continues.
Process.setsid # Become session leader.
exit if fork # Zap session leader. See [1].
Dir.chdir "/" # Release old working directory.
File.umask 0000 # Ensure sensible umask. Adjust as needed.
STDIN.reopen "/dev/null" # Free file descriptors and
STDOUT.reopen "/dev/null", "a" # point them somewhere sensible.
STDERR.reopen STDOUT # STDOUT/ERR should better go to a logfile.
end
OPTIONS = {
:interval => 5.0,
:command => File.expand_path(RAILS_ROOT + '/script/process/spawner'),
:daemon => false
}
ARGV.options do |opts|
opts.banner = "Usage: spinner [options]"
opts.separator ""
opts.on <<-EOF
Description:
The spinner is a protection loop for the spawner, which will attempt to restart any FCGI processes
that might have been exited or outright crashed. It's a brute-force attempt that'll just try
to run the spawner every X number of seconds, so it does pose a light load on the server.
Examples:
spinner # attempts to run the spawner with default settings every second with output on the terminal
spinner -i 3 -d # only run the spawner every 3 seconds and detach from the terminal to become a daemon
spinner -c '/path/to/app/script/process/spawner -p 9000 -i 10' -d # using custom spawner
EOF
opts.on(" Options:")
opts.on("-c", "--command=path", String) { |v| OPTIONS[:command] = v }
opts.on("-i", "--interval=seconds", Float) { |v| OPTIONS[:interval] = v }
opts.on("-d", "--daemon") { |v| OPTIONS[:daemon] = v }
opts.separator ""
opts.on("-h", "--help", "Show this help message.") { puts opts; exit }
opts.parse!
end
daemonize if OPTIONS[:daemon]
trap(OPTIONS[:daemon] ? "TERM" : "INT") { exit }
loop do
system(OPTIONS[:command])
sleep(OPTIONS[:interval])
end