flattie 
A tiny (203B) and fast utility to flatten an object with customizable glue
This module recursively squashes an Object/Array. The output is a flat object – AKA, it has a single level of depth.
By default, the . character is used to glue/join layers' keys together. This is customizable.
Finally, by default, any keys with nullish values (null and undefined) are not included in the return object.
Install
$ npm install --save flattie
Usage
import { flattie } from 'flattie';
flattie({
a: 'hi',
b: {
a: null,
b: ['foo', '', null, 'bar'],
d: 'hello',
e: {
a: 'yo',
b: undefined,
c: 'sup',
d: 0,
f: [
{ foo: 123, bar: 123 },
{ foo: 465, bar: 456 },
]
}
},
c: 'world'
});
// {
// 'a': 'hi',
// 'b.b.0': 'foo',
// 'b.b.1': '',
// 'b.b.3': 'bar',
// 'b.d': 'hello',
// 'b.e.a': 'yo',
// 'b.e.c': 'sup',
// 'b.e.d': 0,
// 'b.e.f.0.foo': 123,
// 'b.e.f.0.bar': 123,
// 'b.e.f.1.foo': 465,
// 'b.e.f.1.bar': 456,
// 'c': 'world'
// }Note:
nullandundefinedvalues are purged by default.
API
flattie(input, glue?, keepNullish?)
Returns: Object
Returns a new object with a single level of depth.
Important: An object is always returned despite
inputtype.
input
Type: Object|Array
The object to flatten.
glue
Type: String
Default: .
A string used to join parent key names to nested child key names.
const foo = { bar: 123 };
flattie({ foo }); //=> { 'foo.bar': 123 }
flattie({ foo }, '???'); //=> { 'foo???bar': 123 }keepNullish
Type: Boolean
Default: false
Whether or not null and undefined values should be kept.
// Note: Applies to Objects too
const foo = ['hello', null, NaN, undefined, /*hole*/, 'world'];
flattie({ foo });
//=> {
//=> 'foo.0': 'hello',
//=> 'foo.2': NaN,
//=> 'foo.5': 'world'
//=> }
flattie({ foo }, '.', true);
//=> {
//=> 'foo.0': 'hello',
//=> 'foo.1': null,
//=> 'foo.2': NaN,
//=> 'foo.3': undefined,
//=> 'foo.4': undefined,
//=> 'foo.5': 'world'
//=> }Benchmarks
Running on Node.js v10.13.0
Load Time:
flat 1.047ms
flatten-object 1.239ms
flat-obj 0.997ms
flattie 0.258ms
Validation:
✔ flat
✔ flatten-object
✔ flat-obj
✔ flattie
Benchmark:
flat x 186,487 ops/sec ±1.28% (86 runs sampled)
flatten-object x 199,476 ops/sec ±1.01% (93 runs sampled)
flat-obj x 393,574 ops/sec ±1.41% (95 runs sampled)
flattie x 909,734 ops/sec ±0.82% (93 runs sampled)
Related
- nestie – A tiny (242B) and fast utility to expand a flattened object
This isflattie's reverse / counterpart.
License
MIT © Luke Edwards