Config Attendant

---

Usage

JS

The only option is to pass Config Attendant the name of your app, and your default configuration.

var conf = require('config-attendant')(appname, {
  //defaults go here.
  port: 2468,
 
  //defaults which are objects will be merged, not replaced
  views: {
    engine: 'jade'
  }
});

Config Attendant will return your configuration options merged with the defaults you specify. If you pass in a predefined defaults object, it will be mutated:

var conf = {};
require('config-attendant')(appname, conf);

If Config Attendant finds any config files for your app, the returned config object will have a configs array containing their paths:

var appCfg = require('config-attendant')(appname, conf);
appCfg.configs[0] // /etc/appnamerc
appCfg.configs[1] // /home/dominictarr/.config/appname
appCfg.config // same as appCfg.configs[appCfg.configs.length - 1]

CLI

Installation

To use Config Attendant as a command line tool (nice for testing out configurations), install it globally via npm.

npm install -g config-attendant

Parameters passed as strings are interpreted as app names, flags and values are interpreted as configuration values.

$ config appname --prop 'value'
{
  "_": [
    "appname"
  ],
  "prop": "value"
}

The only reserved flag is --config which can be used to point to json config files to load as well.

$ config appname --prop 'value' --config config-attendant/test/defaults.json
{
  "option": false,
  "envOption": 24,
  "_": [
    "appname"
  ],
  "prop": "value",
  "config": "config-attendant/test/defaults.json",
  "configs": [
    "config-attendant/test/defaults.json"
  ]
}

Standards

Given your application name (appname), Config Attendant will look in all the obvious places for configuration.

• command line arguments (parsed by minimist)
• environment variables prefixed with ${appname}_
  • or use "__" to indicate nested properties (e.g. appname_foo__bar__baz => foo.bar.baz)
• if you passed an option --config file then from that file
• a local .${appname}rc or the first found looking in ./ ../ ../../ ../../../ etc.
• a local package.json file or the first found looking in ./ ../ ../../ ../../../ etc.
  • within the package.json the ${appname} value.
  • within the package.json, config.${appname}.
• $HOME/.${appname}rc
• $HOME/.${appname}/config
• $HOME/.config/${appname}
• $HOME/.config/${appname}/config
• /etc/${appname}rc
• /etc/${appname}/config
• the defaults object you passed in.

All configuration sources that were found will be flattened into one object, so that sources earlier in this list override later ones.

Configuration File Formats

Configuration files (e.g. .appnamerc) may be in either json or ini format. The example configurations below are equivalent:

Formatted as ini

; You can include comments in `ini` format if you want. 
 
dependsOn=0.10.0
 
 
; Config Attendant has built-in support for ini sections, see? 
 
[commands]
  www     = ./commands/www
  console = ./commands/repl
 
 
; You can even do nested sections 
 
[generators.options]
  engine  = ejs
 
[generators.modules]
  new     = generate-new
  engine  = generate-backend
 

Formatted as json

{
  // You can even comment your JSON, if you want
  "dependsOn": "0.10.0",
  "commands": {
    "www": "./commands/www",
    "console": "./commands/repl"
  },
  "generators": {
    "options": {
      "engine": "ejs"
    },
    "modules": {
      "new": "generate-new",
      "backend": "generate-backend"
    }
  }
}

Comments are stripped from JSON config via strip-json-comments.

Since ini, and env variables do not have a standard for types, your application needs be prepared for strings.

Advanced Usage

Pass in your own argv

You may pass in your own argv object as the third argument to Config Attendant. This is in case you want to use your own command-line opts parser.

require('config-attendant')(appname, defaults, customArgvObject);

Pass in your own parser

If you have a special need to use a non-standard parser, you can do so by passing in the parser as the 4th argument. (leave the 3rd as null to get the default argv object (what minimist parses))

require('config-attendant')(appname, defaults, null, parser);

This may also be used to force a more strict format, such as strict, valid JSON only.

Note on Performance

Config Attendant is running fs.statSync-- so make sure you don't use it in a hot code path (e.g. a request handler)

License

Multi-licensed under the two-clause BSD License, MIT License, or Apache License, version 2.0