# nac nac is a simple app control and monitoring daemon written in node Unlike other process monitors, nac doesn't allow for random spawning and adding of processes. Instead, nac expects you to add "apps" defined by their name and nacfile (procfile-like configuration files) The nacfile allows you to specify many other things about the process, such as arguments, environment variable configuration, working directory, custom scripts etc. nac remembers your apps and will restart them the next time its started. nac is multi-server-aware which allows you to use it with parallel control tools such as [pssh](http://www.theether.org/pssh/), [cssh](http://sourceforge.net/projects/clusterssh/), [fabric](http://docs.fabfile.org/en/1.6/), or, in the future, **rnac** nac can optionally be multi-user aware: a single daemon can run as root and all clients will talk to it. Apps however are run under the uid of the user that added the application, and each user can only control his own apps. # install npm install nac -g # quick start Run the nac daemon. nacd --daemon Create a simple [YAML](http://en.wikipedia.org/wiki/YAML) nacfile for your app in the same directory where your `app.js` resides: ```yaml command: node args: [app.js] env: NODE_ENV: production PORT: 5000 ``` Add the nacfile to git, clone the app on your server and run the commands: $ nac myapp create ~/projects/myapp/nacfile.yaml myapp created (/home/spion/projects/myapp/nacfile.yaml) $ nac myapp start # running as root You can alternatively run the daemon as root. There is no need for concern - it will run apps under the priviledges of the user that added them (by setting the uid and gid). Users can only administer the apps they've added themselves. su root nacd --daemon **Warning!** The root daemon will not read the apps that were added to existing user daemons. Users will need to re-add their apps. # other configuration options There are two types of configuration files in nac: * app configuration (nacfile) * server daemon configuration (nacd.yaml) ### nacfile Here is a complete example nacfile: ```yaml # command to execute. It has to be executable: if using a JS file directly, # use chmod +x file.js first and add a shebang line at the top containing: # #!/usr/bin/env node command: ./myapp-cluster.js # working dir relative to the nacfile cwd: . # extra arguments to add: either an array args: - first - '--other' - third # OR # alternatively you can pass a fancy object args: # long arguments are automatically prefixed with -- longarg: value # one-letter arguments are prefixed with - s: shortarg value # you can add an explicit prefix if you wish --explicit-form: value -e: value # and you can define a list of additional arguments _: [even, more, arguments here] # environment variables env: NODE_ENV: production # clustering is best left to the app, configuration is passed by env vars workers: 4 # you can add additional scripts which will become available as commands for # the specific project scripts: deploy: ./scripts/deploy.sh report: ./scripts/statusReport.sh # if the app dies, nac will attempt to respawn it. the respawn setting # controls the behavior of the respawner. The respawner will begin by # waiting respawn.min seconds before restarting the process, then if the # process keeps dying it will exponentially backoff up to respawn.max seconds # on every respawn attempt. respawn: min: 0.1 max: 30 # override options on a per-server-tag basis servers: two.myapp.com: env: REDIS_SERVER: one.myapp.com one.myapp.com: env: # even though nac doesnt handle clustering, it # can pass clustering configuration via env or args # on a per-server basis workers: 6 REDIS_SERVER: localhost ``` ### nacd.yaml User-level nacd daemons can be configured by creating `~/.config/nac/nacd.yaml` A root-level nacd daemon is configured via `/etc/nacd.yaml` Example `nacd.yaml` for the first server: ```yaml tags: - one.myapp.com - one - myapp-servers ``` Since this server has the tag "one.myapp.com", it will apply the specified config overrides for that tag # available commands #### create nac myapp create nacfile.yaml Adds the specified app with its nacfile to the daemon. The name specified must be unique for that server and user. If the user already has an app running under that name, on that server, nac will complain. #### start, stop, restart nac myapp [start|stop|restart] Start/stop/restart the app `myapp` using the command, arguments and environment variables specified in the config file. #### kill nac myapp kill Send the specified named signal to the app's process. Useful for user-defined signals such as cluster reloading #### destroy nac myapp destroy Will remove the project and its nacfile from the daemon and stop the app process #### update nac myapp update [configpath] Will update the configuration file. If you omit the path, `nacd` will attempt to reload the configuration file from the same location as previously specified. If you specify the config path, `nacd` will update the apps's configuration and update the location of the config file for that app #### logs nac myapp logs Show stdout/stderr logs for the project. Logs will be displayed in the format [date] [time] [stdout|stderr]: content Arguments: * --tag - show just stdout * --last - show last N lines in log (default 100) * --past