easy-config is a simple configuration loader for node projects.

Installation

$ npm install easy-config

Usage

easy-config loads configuration from JSON files and the command line returning an object containing the sum of configurations.

Default usage

Simply require the module and thats it

var config = require('easy-config');

It will try to read JSON files from config subfolder. Starting with an empty object extend the configuration object by adding or overwriting the values obtained in the following order

1. config.json
2. all config files except environment files are added under ns key in the following format -> config.keys.json will be under ns.keys
3. config.dev.json (this is because default environment is development)
4. environment variables
5. command line input

Command line

Input is expected in the --{name}={value} format.

You can also set nested properties by using dots to specify the nesting like so:

$ node test.js --log.level.is=true

You can also omit the value if it is boolean, so the last line is equal to:

$ node test.js --log.level.is

Environment variables

Easy config will also load environment variables into the configuration.

Variables are expected in the format NODE_{name}=value

Nested variables are possible with underscore separators.

The following example is the equivalent of previous command line example

$ export NODE_LOG_LEVEL_IS=true  
$ node test.js

NB! Environment variables are case insensitive - that means if I set an environment variable like

$ export NODE_VAR=10

Then config.var === 10 instead of config.VAR === 10

Also if I have a configuration variable like config.clientId === 'joonas'

Then setting environment variable $ export NODE_CLIENTID='karl' will overwrite the variable and config.clientId === 'karl'

Options

The following options are available:

• folder: *The configuration folder will default to process.cwd() + '/config'
• cmd: *Whether to load configurations from the command line will default to true
• envs: *Array of environment names. These files will not be loaded by default. Will default to ['dev','pro']
• env: *Environment for which to load configuration will default to 'dev' (this will try to load config.dev.json)
• envVars: *Whether to load environment variables, defaults to true
• type: *String -> file extension to load, defaults to JSON. Files are included with require, so js and json files are supported by default.
• pre: *Object to start extending, defaults to {}
• ns: *Boolean whether to append files under ns property
• envPrefix: *String - string to use in matching environment variables related to config, defaults to 'NODE_'

There are three ways of specifying the options:

loadConfig

You can modify the loading options by using the method loadConfig(options) that is on the configuration object.

var config = require('easy-config').loadConfig(options);

Command line

You can also specify the loading options from the command line in the following format -{name}={value}.

Take note that the format differs between loading configuration options and configuration extending by one '-' sign.

Options specified on command line will take precedent over options specified in code.

$ node test.js -env=pro

env.json

The environment variables can also be defined in a 'env.json' file that is loaded from the current working directory of the process. These are used as the base and extend the defaults before all other methods.

CJSON support

Optionally if you have the cjson module installed, then you can also use comments in your json files as it will be used to load them.

Examples

config.json:

{
  "log":{
    "name":"It's useful to log",
    "level":"info"
  }
}

config.dev.json:

{
  "log":{
    "level":"debug"
  },
  "correct":true
}

index.js

var config = require('easy-config');
console.log(config);

Will create the following output:

{
  log:{
    name:"It's useful to log",
    level:"debug"
  },
  correct:true
}

Namespaces

Namespaces option allows to load multiple configuration files into their own namespace

Having config.runner.json { "name":"runner" }

Will create the following

{
  ...
  ns:{
    runner:{
      name:"runner"
    }
  }
}

Extend

The config object also comes with the convenience method of extend to allow overwriting or extending the configuration object.

Usage:

var config = require('easy-config').extend({newProp:true});

Will result in:

{
  ...
  newProp:true
}

You can also extend arbitrary objects by calling extend with 2 objects. The second object will overwrite the first object.

Usage:

var config = require('easy-config');
config = config.extend({newProp:true,oldProp:'Old'},{newProp:false, newestProp:'Newest'});

Will result in:

{
  newProp:false,
  oldProp:'Old',
  newestProp:'Newest'
}

When using extend with two objects you can also pass boolean true as the third argument, this will change the default behaviour of cloning the objects to changing the original object at first parameter.

Modify/unmodify

You can modify the config object so that the modification persist over the next requrie calls.

Usage:

var config = require('easy-config');
config.modify({newProp:true});
console.log(require('easy-config'));

Will result in:

{
  ...
  newProp:true
}

You can undo the modifications by calling unmodify

Usage:

var config = require('easy-config');
config.modify({newProp:true});
config.unmodify();
console.log(require('easy-config'));

Will result in:

{
  ...
}

File manipulation

easy-config also provides some file manipulation functions for easy configuration file modifying if a need should arise for a persistent cross process on the fly dynamic configuration

writeConfigFile(name, object)

writeConfigFile is a function for writing a new configuration file or overwriting an existing file. The function takes two parameters:

• name -> the name of the new file 'config.new.json' and 'new' are equivalent
• object -> this object will be JSON.stringified before writing to file

The function will return the new configuration object or false if writing fails

changeConfigFile(name, object)

changeConfigFile is a function for extending the json object in a file with new data. The function takes two parameters:

• name -> the name of the new file 'config.new.json' and 'new' are equivalent
• object -> the previous contents will be extended with this object and the result written to file

The function will return the new configuration object or false if writing fails

deleteConfigFile(name)

deleteConfigFile is a function for deleting a configuration file

• name -> the name of the new file 'config.new.json' and 'new' are equivalent

Function returns new configuration object or false if no such file is mapped.

getDefinedOptions()

getDefinedOptions is a function for getting the easy-configs inner options object

Function returns the current options object of the config.

isProduction()

isProduction is a function for getting a boolean indication if production config is used

Function returns boolean true or false

isEnvironment(name | array)

isEnvironment is a function for getting a boolean indication if the environment in use is the one specified or in the array specified

Function returns boolean true or false

License

The MIT License (MIT) Copyright (c) 2012 Karl Düüna

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.