Possibility to use references to sub config parts

[stalniy]

Expected Behavior:

I have several functions which consumes own configuration + logger configuration, so I'd like to reference logger configuration from another configuration (Such behavior exists in Ruby on Rails Yaml parser, more info)

{
  domainTracker: {
     "logger": {
        "<<":  "*logger",
     }
     "path": "/api"
  },

  "errorHandler": {
     "logger": {
        "<<":  "*logger",
     }
     "debug": true
  },

  "logger": {
     "server": "..."
  }
}

afterwards when I do config.get('domainTracker') I expect logger configuration to be included as part of domainTracker configuration:

const config = config.get('domainTracker');

/*
{
  "domainTracker": {
     "logger": { "server": "...." },
     "path": "/api"
  }
}
*/

callMe(config);

Actual Behavior:

I need manually pass different configurations into my functions:

callMe(config.get('domainTracker'), config.get('logger'));

This is a bit inconvenient in case if you want all your functions to have standardized API (e.g., single argument with options object) and configure each function independently. So, this can be called kind of "Config injection" feature :)

[markstos]

You can refer to other parts of the configuration when using the JavaScript file format and defer() functions as documented here: https://github.com/lorenwest/node-config/wiki/Configuration-Files#javascript-module---js

If you want to store parts of the configuration in JSON, the JavaScript config file format can read in JSON files.

Does that address your need?

[stalniy]

Actually I would prefer to keep my config simple and not use JS.

It would be good at least to provide a simple way to register key processor, so I can implement this as a separate extension

[iMoses]

@markstos I think it can be closed..
The new Parser enables the ability to create such customizable parsers..