Deep-key-mirror NPM

Deep Key Mirror

Alternative to React's keyMirror which further mirrors properties deep inside the object graph.

Installation

npm install deep-key-mirror

Usage

1. `deepKeyMirror(obj, [config])`

Returns a new object that has values equal to its property names in the given object.

Simple example

import deepKeyMirror from 'deep-key-mirror';

deepKeyMirror({ null: '', age: null }); // { name: 'name', age: 'age' }

If the given object has child arrays or objects, they are also "key-mirrored" recursively, with the .-concatenated paths from the root object assigned to each of their value.

Nested example

import deepKeyMirror from 'deep-key-mirror';

const breakfast = {
  bread: null,
  beverage: {
    milk: null,
    coffee: null,
    beer: 'BEER!',
  },
  fruits: ['orange', 'apple'],
};
const mirrored = deepKeyMirror(breakfast);
/*
mirrored === {
  bread: 'bread',
  beverage: {
    milk: 'beverage.milk',
    coffee: 'beverage.coffee',
    beer: 'beverage.beer'
  },
  fruits: {
    orange: 'fruits.orange',
    apple: 'fruits.apple'
  }
}
*/

2. `matrix(string[][], [config])`

Converts an two-dimensional dimensional array into an object with an isomorphic key-value structure.

Example

const restApi = matrix([
  ['user', 'team', 'group'],
  ['get', 'getList', 'post', 'put', 'delete'],
  ['request', 'success', 'failure'],
]);
/*
 restApi === {
   user: {
     get:     { request: 'user.get.request',      success: 'user.get.success',      failure: 'user.get.failure' },
     getList: { request: 'user.getList.request',  success: 'user.getList.success',  failure: 'user.getList.failure' },
     post:    { request: 'user.post.request',     success: 'user.post.success',     failure: 'user.post.failure' },
     put:     { request: 'user.put.request',      success: 'user.put.success',      failure: 'user.put.failure' },
     delete:  { request: 'user.delete.request',   success: 'user.delete.success',   failure: 'user.delete.failure' },
   },
   team: {
     get:     { request: 'team.get.request',      success: 'team.get.success',      failure: 'team.get.failure' },
     getList: { request: 'team.getList.request',  success: 'team.getList.success',  failure: 'team.getList.failure' },
     post:    { request: 'team.post.request',     success: 'team.post.success',     failure: 'team.post.failure' },
     put:     { request: 'team.put.request',      success: 'team.put.success',      failure: 'team.put.failure' },
     delete:  { request: 'team.delete.request',   success: 'team.delete.success',   failure: 'team.delete.failure' },
   },
   group: {
     get:     { request: 'group.get.request',     success: 'group.get.success',     failure: 'group.get.failure' },
     getList: { request: 'group.getList.request', success: 'group.getList.success', failure: 'group.getList.failure' },
     post:    { request: 'group.post.request',    success: 'group.post.success',    failure: 'group.post.failure' },
     put:     { request: 'group.put.request',     success: 'group.put.success',     failure: 'group.put.failure' },
     delete:  { request: 'group.delete.request',  success: 'group.delete.success',  failure: 'group.delete.failure' },
   }
 }
 */

`config`

Both deepKeyMirror and matrix can take config object as a second argument, which has these three options

prop	type	default	description
`retain`	boolean	false	When set to `true`, primitive values other than `null` or `undefined` won't be replaced
`joinString`	string	`'.'`	Separator for joining object paths.
`upperCase`	boolean	false	When set to `true`, values will be mirrored with uppercase.

examples

const props = {
  color: {
    red: null,
    green: 42,
    blue: 'not_an_yellow',
    other: {
      brown: 'maroon',
      darkness: ['bright', 1, false],
    },
  },
};

deepEqual(deepKeyMirror(props, { retain: true }), {
  color: {
    red: 'color.red',
    green: 42,
    blue: 'color.not_an_yellow',
    other: {
      brown: 'color.other.maroon',
      darkness: {
        '1': 1,
        bright: 'color.other.darkness.bright',
        false: false,
      },
    },
  },
});

deepEqual(deepKeyMirror(props, { joinString: '-' }), {
  color: {
    red: 'color-red',
    green: 'color-green',
    blue: 'color-blue',
    other: {
      brown: 'color-other-brown',
      darkness: {
        '1': 'color-other-darkness-1',
        bright: 'color-other-darkness-bright',
        false: 'color-other-darkness-false',
      },
    },
  },
});

deepEqual(deepKeyMirror(props, { upperCase: true }), {
  color: {
    red: 'COLOR.RED',
    green: 'COLOR.GREEN',
    blue: 'COLOR.BLUE',
    other: {
      brown: 'COLOR.OTHER.BROWN',
      darkness: {
        '1': 'COLOR.OTHER.DARKNESS.1',
        bright: 'COLOR.OTHER.DARKNESS.BRIGHT',
        false: 'COLOR.OTHER.DARKNESS.FALSE',
      },
    },
  },
});