Deeks NPM | npm.io

deeks - Deep Object Key Extraction

Retrieve all keys and nested keys from objects and arrays of objects.

Installing

npm install --save deeks

Example:

const { deepKeys } = require('deeks');
// Alternatively:
// import { deepKeys } from 'deeks';

let generatedKeys = deepKeys({
	make: 'Nissan',
	model: 'GT-R',
	trim: 'NISMO',
	specifications: [
	    {mileage: 10},
	    {cylinders: 6}
	]
}, {
    expandArrayObjects: true,
    ignoreEmptyArraysWhenExpanding: true
});
// => ['make', 'model', 'trim', 'specifications.mileage', 'specifications.cylinders']

API

deepKeys

deepKeys(object, options)

Returns all keys in an object, even if they're nested several layers deep. The array of keys that is returned can then be used with the doc-path module to get and set values at a specific key path.

Options (optional):

arrayIndexesAsKeys - Boolean (Default false) - Should array indexes be used as keys in the generated path? - Example:

	```json
	[
		{
			"list": [
				{
					"a": 1
				},
				{
					"a": 2
				}
			]
		}
	]
	```
	- arrayIndexesAsKeys = `false` results in: `['list.a']`
	- arrayIndexesAsKeys = `true` results in: `['list.0.a', 'list.1.a']`

expandNestedObjects - Boolean (Default: true) - Should nested objects appearing in the provided object also be expanded, such asthat keys appearing in those objects are extracted and included in the returned key path list? - Example:

	```json
	{
		"make": "Nissan",
		"model": "Murano",
		"year": 2013,
		"specifications": {
			"mileage": 7106,
			"trim": "S AWD"
		}
	}
	```
	- expandNestedObjects = `false` results in: `['make', 'model', 'year', 'specifications']`
	- expandNestedObjects = `true` results in: `['make', 'model', 'year', 'specifications.mileage', 'specifications.trim']`

expandArrayObjects - Boolean (Default: false) - Should objects appearing in arrays in the provided object also be expanded, such that keys appearing in those objects are extracted and included in the returned key path list? - Example:

```json
{
	"make": "Nissan",
	"model": "GT-R",
	"trim": "NISMO",
	"specifications": [
		{"mileage": 10},
		{"cylinders": 6}
	]
}
```
- expandArrayObjects = `false` results in: `['make', 'model', 'trim', 'specifications']`
- expandArrayObjects = `true` results in: `['make', 'model', 'trim', 'specifications.mileage', 'specifications.cylinders']`

ignoreEmptyArraysWhenExpanding - Boolean (Default: false) - Should empty array keys be ignored when expanding array objects? - Note: This only has an effect when used with expandArrayObjects. - Example:

	```json
	{ 
		"features": [ {"name": "A/C" }],
		"rebates": []
	}
	```
	- ignoreEmptyArraysWhenExpanding = `false` results in: `['features.name', 'rebates']`
	- ignoreEmptyArraysWhenExpanding = `true` results in: `['features.name']`

escapeNestedDots - Boolean (Default: false) - Should . characters that appear in keys be escaped with a preceding \ character? - Example:

	```json
	{
		"a.a": "1",
		"a.b": {
			"c": "2",
			"c.d": "3"
		}
	}
	```
	- escapeNestedDots = `false` results in: `['a.a', 'a.b.c', 'a.b.c.d']`
	- escapeNestedDots = `true` results in: `['a\\.a', 'a\\.b.c', 'a\\.b.c\\.d']`

ignoreEmptyArrays - Boolean (Default: false) - Should key paths for empty arrays be ignored in the generated key list? - Example:

	```json
	{
		"a": {
			"b": [],
			"c": {
				"f": 4,
				"e": []
			}
		},
		"b": []
	}
	```
	- ignoreEmptyArrays = `false` results in `['a.b', 'a.c.f', 'a.c.e', 'b']`
	- ignoreEmptyArrays = `true` results in `['a.c.f']`

Returns: string[]

Example: ['make', 'model', 'specifications.odometer.miles', 'specifications.odometer.kilometers']

deepKeysFromList

deepKeysFromList(array, options)

Returns all keys in each object in the array, even if the keys are nested several layers deep in each of the documents. These can also be used with the doc-path module.

Options (optional):

	```json
	{
		"make": "Nissan",
		"model": "Murano",
		"year": 2013,
		"specifications": {
			"mileage": 7106,
			"trim": "S AWD"
		}
	}
	```
	- expandNestedObjects = `false` results in: `['make', 'model', 'year', 'specifications']`
	- expandNestedObjects = `true` results in: `['make', 'model', 'year', 'specifications.mileage', 'specifications.trim']`

```json
{
	"make": "Nissan",
	"model": "GT-R",
	"trim": "NISMO",
	"specifications": [
		{"mileage": 10},
		{"cylinders": 6}
	]
}
```
- expandArrayObjects = `false` results in: `['make', 'model', 'trim', 'specifications']`
- expandArrayObjects = `true` results in: `['make', 'model', 'trim', 'specifications.mileage', 'specifications.cylinders']`

	```json
	[
		{ "features": [ {"name": "A/C" }] },
		{ "features": [] }
	] 
	```
	- ignoreEmptyArraysWhenExpanding = `false` results in: `[ ['features.name', 'features'] ]`
	- ignoreEmptyArraysWhenExpanding = `true` results in: `[ ['features.name'] ]`

escapeNestedDots - Boolean (Default: false) - Should . characters that appear in keys be escaped with a preceding \ character. - Example:

	```json
	[
		{
			"a.a": "1",
			"a.b": {
				"c": "2",
				"c.d": "3"
			}
		}
	]
	```
	- escapeNestedDots = `false` results in: `[ ['a.a', 'a.b.c', 'a.b.c.d'] ]`
	- escapeNestedDots = `true` results in: `[ ['a\\.a', 'a\\.b.c', 'a\\.b.c\\.d'] ]`

ignoreEmptyArrays - Boolean (Default: false) - Should key paths for empty arrays be ignored in the generated key list? - Example:

	```json
	[
		{
			"a": {
				"b": [],
				"c": {
					"f": 4,
					"e": []
				}
			},
			"b": []
		}
	]
	```
	- ignoreEmptyArrays = `false` results in `[ ['a.b', 'a.c.f', 'a.c.e', 'b'] ]`
	- ignoreEmptyArrays = `true` results in `[ ['a.c.f'] ]`

Returns: string[][]

Example: [ ['make', 'model', 'specifications.odometer.miles', 'specifications.odometer.kilometers'] ]

Examples

This module integrates really nicely with the doc-path module, which allows the programmatic getting and setting of key paths produced by this module.

Additionally, doc-path@>=3 works with the keys returned when the escapeNestedDots option is specified.

Here's an example of how this works:

const path = require('doc-path'),
      { deepKeys } = require('deeks');

let car = {
		make: 'Nissan',
		model: 'GT-R',
		trim: 'NISMO',
		specifications: {
			mileage: 10,
			cylinders: '6'
		}
	},
	
	carKeys = deepKeys(car);

for(let keyPath of carKeys) {
    // Clear all values
    path.setPath(car, keyPath, '');
}