frozenv v1.0.3

Frozenv

Node.js library that helps you set read-only environment variables under a specific namespace.

// Require the package
var Frozenv = require('frozenv');

// Set your environment variables
Frozenv.setVars('Cars', {
  gti: {
    make: 'Volkswagen',
    year: '2009'
  },
  cooper_s: {
    make: 'Mini',
    year: '2005'
  }
});

// Access your environment variables
console.log(process.Cars.gti);
console.log(process.Cars.cooper_s);

Installation

• npm

  $ cd /path/to/your/project
  $ npm install --save frozenv

• Git

  $ git clone https://github.com/crookse/frozenv.git /path/to/your/project

Documentation

Frozenv.setVars(namespace, variables)

Purpose

Allows you to set read-only environment variables under a specific namespace under the process variable.

• Note: Periods in the namespace argument will create nested namespaces. For example, Frozenv.setVars('this.is.my.namespace', {}) will create process.this.is.my.namespace and not process['this.is.my.namespace'].

• Note: If a preexisting namespace is specified, then it must not already be frozen in order for Frozenv.setVars() to work. For example, the below will not work because Garage.Cars will be frozen after it's used in the first Frozen.setVars() call:

  // Require the package
  var Frozenv = require('frozenv');
  
  // Set your environment variables
  Frozenv.setVars('Garage.Cars', {
    gti: {
      make: 'Volkswagen',
      year: '2009'
    },
    cooper_s: {
      make: 'Mini',
      year: '2005'
    }
  });
  
  // Set more environment variables in the Garage.Cars namespace
  Frozenv.setVars('Garage.Cars', {
    is_350_f_sport: {
      make: 'Lexus',
      year: '2017'
    }
  });

  Frozenv.setVars('env.MyNamespace', {}) will work because env is not frozen until you use it in a Frozenv.setVars() call.

• Note: This function calls Frozenv.freezeObject() to freeze the variables argument and all of its nested objects and properties.

Type

<Function>

Parameters

namespace <String>

• The namespace to use under the process variable.

variables <Object>

• The variables to set as frozen environment variables.

Throws

Nothing

Returns

Nothing

Example Usage

• Setting environment variables under a namespace:

  // Require the package
  var Frozenv = require('frozenv');
  
  // Set your environment variables
  Frozenv.setVars('Cars', {
    gti: {
      make: 'Volkswagen',
      year: '2009'
    },
    cooper_s: {
      make: 'Mini',
      year: '2005'
    }
  });
  
  // Access your environment variables
  console.log(process.Cars.gti);
  console.log(process.Cars.cooper_s);

• Setting environment variables under a nested namespace:

  // Require the package
  var Frozenv = require('frozenv');
  
  // Set your environment variables
  Frozenv.setVars('Garage.Cars', {
    gti: {
      make: 'Volkswagen',
      year: '2009'
    },
    cooper_s: {
      make: 'Mini',
      year: '2005'
    }
  });
  
  // Access your environment variables
  console.log(process.Garage.Cars.gti);
  console.log(process.Garage.Cars.cooper_s);

Frozenv.freezeObject(object)

Purpose

Allows you to freeze an object including its nested objects and properties.

Type

<Function>

Parameters

object <Object>

• The object to freeze.

Throws

Nothing

Returns

Nothing

Example Usage

• Freezing an object:

  // Require the package
  var Frozenv = require('frozenv');
  
  // Define your object
  var object = {
    status: 'I am frozen.'
  };
  
  // Freeze your object
  Frozenv.freezeObject(object);
  
  // Try to change your object's properties
  try {
    object.status = 'changed';
  } catch (error) {
    console.log(error);
  }
  
  // Access your object to see that nothing has changed
  console.log(object);

• Freezing an object with nested objects:

  // Require the package
  var Frozenv = require('frozenv');
  
  // Define your object
  var object = {
    status: 'I am frozen.',
    nested_object: {
      status: 'I am frozen.',
    }
  };
  
  // Freeze your object
  Frozenv.freezeObject(object);
  
  // Try to change your object's nested object's properties
  try {
    object.nested_object.status = 'changed';
  } catch (error) {
    console.log(error);
  }
  
  // Access your object to see that nothing has changed
  console.log(object);

License

MIT