Go daemon (or just god) is a utility to "daemonize" Go programs that originally only run in foreground and write logs to the console.
Go daemon can turn these programs into daemons by managing essential aspects of their execution. The process of making a program become a daemon has very peculiar steps and can be done outside the code. This is what god is for.
It executes a program for you doing things that daemons do: switch to another user and group, switch the directory of execution, detach from the terminal and create a pid file. While the program runs, god consumes its output (stdout and stderr) and write to a log file using minimum system resources.
It also handles all signals (SIGINT, SIGTERM, etc) and forward them to the program being managed. On SIGHUP, god recycles its log file making it easy to integrate with logrotate. If SIGHUP is not supported by your program, god can handle the signal itself and not forward it, making your program immune to hangups.
Go daemon is inspired by twistd, but primarily for running servers written in the Go Programming Language that don't (or just can't) care about daemonizing. However, it can also be used for running php, python and any other type of long lived programs that need to be daemonized.
A typical command line looks like this:
god --nohup --logfile foo.log --pidfile foo.pid --user nobody --group nobody --rundir /opt/foo -- ./foobar --foobar-opts
Like if there's not enough options out there: upstart, systemd, launchd, daemontools, supervisord, runit, you name it. There's also utilities like apache's logger, etc.
Go daemon aims at being as simple as possible in regards to deployment and usage, and to run with minimum resources. It doesn't supervise the program, just run it as a daemon and takes care of its console output. It mixes well with upstart and logrotate, for example.
Go daemon is not needed on systems with systemd.
Go daemon is written in C and needs to be compiled. Debian and Ubuntu can install the compiler and tools with the following command:
apt-get install build-essential
Then build and install it:
make
make install
The god command line tool should be ready to use.
Go daemon can be packaged for both debian and rpm based systems and has been tested on Ubuntu, CentOS and RHEL.
Ubuntu 12.04 packages are available at https://launchpad.net/~fiorix/+archive/go-daemon/ and can be installed with following commands:
apt-get install python-software-properties
add-apt-repository ppa:fiorix/go-daemon
apt-get update
apt-get install go-daemon