README.md
# Nand [](http://badge.fury.io/rb/nand) [](https://codeclimate.com/github/linkodehub/nand) [](https://gitter.im/linkodehub/nand?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
### Overview
Nand is a simple CLI tool to make anything daemon by Ruby.
Nand is the meaning of Nandemo of Japanese.
Nandemo of here is a executable file and shell command, a non-executable Ruby file.
For starting daemonize TARGET, You can just type `nand start TARGET`.
You can stop by `nand stop TARGET`. `nand status TARGET` show it running status.
## Installation
Add this line to your application's Gemfile:
gem 'nand'
And then execute:
$ bundle
Or install it yourself as:
$ gem install nand
## Easy Usage
### Command Definition
$ nand SUB_COMMAND TARGET [OPTION]
### Start
$ cd /any/path
$ nand start sleep 1000
sleep is Start Success [85596]
You can start TARGET by `start` SUB_COMMAND.
Though OPTION(s) after TARGET is Nand option, OPTION(s) Nand is unknown,
will be handed over to TARGET.
Here `1000` is handed over to `sleep`.
And Nand recognizes a shell command `sleep` as TARGET name.
When TARGET is success to be a daemon process, Nand show TARGET namd and daemon
process id.
### Status
For the TARGET `sleep` running status, Nand `status` command show running status.
$ cd /any/path
$ nand status sleep
sleep is Running [85596] by USER in /any/path
You can omit the TARGET name `sleep` because you stay in `/any/path`.
### Stop
Nand `stop` command stop daemon process with TARGET name.
$ nand stop sleep
sleep is Stopped [85596]
$ nand status sleep
sleep is Not Running in /any/path
You can also omit the TARGET name `sleep` as `status` because you stay in `/any/path`.
## A Ruby File
Following `forever_sleep.rb` in current directory, you can make it daemon with
file name as TARGET name.
```ruby:forever_sleep.rb
require 'nand/plugin'
module Sample
class ForeverSleep
extend Plugin
def self.executor(*argv)
new(*argv)
end
def exec
sleep
end
end
end
```
$ nand start forever_sleep.rb -p Sample::ForeverSleep
forever_sleep.rb is Start Success [86326]
$ nand stop forever_sleep.rb
forever_sleep.rb is Stopped [86326]
Nand can find the executor with exec method from defined class by `-p` option.
The class need to extend `Nand::Plugin`.
Then then executor can become a daemon process as TARGET name `forever_sleep.rb`.
## More Usage
### Avoid duplicated Nand Options
There are two ways to avoid duplicated Nand options for daemon's process options.
First, the options can be enclosed in "(double) or '(single) quatations.
$ nand start any.sh "--run_dir /tmp"
Others, you can put them after double dash(--).
$ nand start any.sh -- --run_dir /tmp
### Pipes to Daemon Process
You can pipe to daemon process STDOUT and STDERR, STDIN by using Nand options
`--out` and `--err`, `--in`.
Here is `sleep_echo.sh` as follows:
```sh
#!/bin/sh
sleep $1
echo $2
```
Then you can start with Nand pipe option.
$ nand start sleep_echo.sh 100 '"foo bar baz"' --out out.log
$ cat out.log
foo bar baz
### Running Directory
It is very important that you define the running directory with Nand option `--run_dir`.
A PID file is put in the running directory and daemon process change the running directory.
If you don't define the running directory, it is the current directory.
$ nand start sleep_echo.sh 100 abc --run_dir /tmp --out out.log
### Prohibition of Duplicated Start
Basically, you can not start duplicated daemon process name.
$ nand start sleep 1000
sleep is Start Success [97649]
$ nand start sleep 1000
sleep is Start Failed [PID file exist /any/path/.nand_sleep.pid]
If you would like to start duplicated daemon process name, you can
start in another run directory or as another daemon process name.
$ nand start sleep 1000 --run_dir /tmp
sleep1 is Start Success [97611]
$ nand start sleep 1000 -n sleep1
sleep1 is Start Success [97649]
$ nand status -a
sleep is Running [97649] by USER in /run/dir
sleep1 is Running [97765] by USER in /run/dir
sleep is Running [97611] by USER in /tmp
### Automatically Stop
Daemon process can automatically stop at the time limit, you defined.
$ nand start vmstat 5 --sec 600
Then `vmstat` will automatically stop after the lapse of 600 seconds.
### Automatically Recovery
If you defined Nand `-r` option, when the daemon process downed,
it would restart.
$ nand start sleep 100 -r
This `sleep 100` will be down after 100 seconds, then `sleep 100`
will restart soon.
## Note
When `nand stop`, Nand send signal(SIGTERM) to daemon process group, and
wait for termination of daemon process. Your daemon process finish by receiving
a SIGTERM.
You must not remove a PID file for Nand `.nand_[DAEMON_NAME].pid`.
It has be required to confirm integrity.
If you removed it, Nand output an error. Then you need to stop
the daemon process manually.
## Contributing
1. Fork it
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create new Pull Request
## License
MIT