cconfig

cconfig

cconfig is a simple cascading config system. It provides a simple, but easily overrideable, solution for environment specific application config.

cconfig loads a config.js or config.json file from your process.cwd(). If it finds that object, it will look for a property in it matching process.env.NODE_ENV (if undefined, it will use NODE_ENV=development) and overwrite any environment-specific properties found there. Then, it will overwrite that object using process.env.

With cconfig you can define global and environment specific config values, and override them using command line level or system level environment variables.

Installation

    npm install cconfig

Setup and usage

    NODE_ENV=development node myscript.js

cconfig uses the NODE_ENV env var to provide environmenet-specific configuration settings. Available settings include process environment variables provided to the process, as well as global and environment-specific settings specified in a config.json file.

config.js || config.json

cconfig can be loaded to expect a config.json or config.js file in the process' base directory cwd:

    var config = require('cconfig')(); 

or you may specify a config file location (this is useful when your application is running in a different directory than where the config.js/config.json resides):

    var config = require('cconfig')('./path/to/my/config.json'); 
    // ----- OR -----
    var config = require('cconfig')('./path/to/my/config.js')

alternatively, you may chose to provide an object as a base configuration

    var defaultConfig = { port: 1337 }
    var config = require('cconfig')(defaultConfig)

Cascading Overrides

The configuration provided through a file or object may include global values and values particular to any NODE_ENV environment name that may be specified. Global variables specified in config.json will override any process environment variable values, and environment-specific items in config.json will override default values defined there as well.

    {
      "MULTI_ENV_VAR": "this var will be used in all environments",
      "OVERRIDEABLE_VAR": "this var will be used, unless overriden for another environment",
      "development": {
        "ANOTHER_VAR": "mongodb://somevalue:27017/somedb"
      },
      "staging": {
        "ANOTHER_VAR": "mongodb://somevalue2:27017/somedb,
        "OVERRIDEABLE_VAR": "this var will be used for staging, unless overriden for another environment",
      },
      "production": {
        "ANOTHER_VAR": "mongodb://somevalue3:27017/somedb,
        "OVERRIDEABLE_VAR": "this var will be used for production, unless overriden for another environment",
      }
    }

usage is simple:

assuming node myApp.js or NODE_ENV=development node myApp.js:

    var config = require('cconfig')();
    
    console.log(config.NODE_ENV); // prints "development"
    console.log(config.MULTI_ENV_VAR"); // prints "this var will be used in all environments"
    console.log(config.OVERRIDEABLE_VAR"); // prints "this var will be used, unless overriden for another environment"
    console.log(config.ANOTHER_VAR"); // prints "mongodb://somevalue:27017/somedb"

assuming NODE_ENV=staging node myApp.js:

    var config = require('cconfig')();
    
    console.log(config.NODE_ENV); // prints "staging"
    console.log(config.MULTI_ENV_VAR"); // prints "this var will be used in all environments"
    console.log(config.OVERRIDEABLE_VAR"); // prints "this var will be used, unless overriden for another environment"
    console.log(config.ANOTHER_VAR"); // prints "mongodb://somevalue2:27017/somedb"

Individual values can be overriden by environment variables specified globally or inline as well.

assuming: OVERRIDEABLE_VAR="text straight from the command line" NODE_ENV=production node myApp.js:

    var config = require('cconfig')();
    
    console.log(config.NODE_ENV); // prints "production"
    console.log(config.MULTI_ENV_VAR"); // prints "this var will be used in all environments"
    console.log(config.OVERRIDEABLE_VAR"); // text straight from the command line"
    console.log(config.ANOTHER_VAR"); // prints "mongodb://somevalue3:27017/somedb"

It's possible to override nested properties from the command line as well. Assuming a config.js file similar to the following:

module.exports = {
    BROKER: {
        HOST: 'localhost'
        PORT: 1243
    }
}

The PORT property can be overriden from the command line via: "BROKER.PORT"=1235 node myApp.js. If you're coding on Windows and want to be able to use similar behavior, see the very useful package cross-env.

Run the tests

    npm test