Daemon launching and management made dead simple.
With daemon-spawn you can start, stop and restart processes that run in the background. Processed are tracked by a simple PID file written to disk.
In addition, you can choose to either execute ruby in your daemonized process or 'exec' another process altogether (handy for wrapping other services).
WRITING A DAEMON
To create a new spawner, write a class that extends DaemonSpawn::Base and provides start and stop methods. For example:
class MyServer < DaemonSpawn::Base def start(args) # process command-line args # start your bad self end def stop # stop your bad self end end MyServer.spawn!(:log_file => '/var/log/echo_server.log', :pid_file => '/var/run/echo_server.pid', :sync_log => true, :working_dir => File.dirname(__FILE__))
If you need command-line parameters, any arguments passed after one of the commands (start, stop, status or restart) will be passed to the start method.
The spawn! method takes a hash of symbolized keys. At a minimum you must specify the :working_dir option. You can also override the default locations for the log and PID files.
If you pass a :processes option to the spawn!, daemon spawn will start that number of processes.
See the test/servers directory for working examples.
RUNNING A DAEMON
Let's say that you have the example script listed above in bin/my_server. Here are the commands for starting, querying the status, restarting and stopping the daemon:
bin/my_server start bin/my_server status bin/my_server restart bin/my_server stop
Note that if any additional arguments are passed to either start or restart those will be passed to the start method of an instance of your daemon class.
Feel free to fork this project and send me pull requests with any changes that you have. Please note that I won't accept any patches with significant formatting changes or ones without tests.
sudo gem install daemon-spawn
(The MIT License)
Copyright © 2009 Evri, Inc.
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