304 lines
7.1 KiB
Markdown
304 lines
7.1 KiB
Markdown
# dot-prop
|
|
|
|
> Get, set, or delete a property from a nested object using a dot path
|
|
|
|
## Install
|
|
|
|
```sh
|
|
npm install dot-prop
|
|
```
|
|
|
|
## Usage
|
|
|
|
```js
|
|
import {getProperty, setProperty, hasProperty, deleteProperty} from 'dot-prop';
|
|
|
|
// Getter
|
|
getProperty({foo: {bar: 'unicorn'}}, 'foo.bar');
|
|
//=> 'unicorn'
|
|
|
|
getProperty({foo: {bar: 'a'}}, 'foo.notDefined.deep');
|
|
//=> undefined
|
|
|
|
getProperty({foo: {bar: 'a'}}, 'foo.notDefined.deep', 'default value');
|
|
//=> 'default value'
|
|
|
|
getProperty({foo: {'dot.dot': 'unicorn'}}, 'foo.dot\\.dot');
|
|
//=> 'unicorn'
|
|
|
|
getProperty({foo: [{bar: 'unicorn'}]}, 'foo[0].bar');
|
|
//=> 'unicorn'
|
|
|
|
getProperty({foo: [{bar: 'unicorn'}]}, 'foo.0.bar');
|
|
//=> 'unicorn'
|
|
|
|
// Setter
|
|
const object = {foo: {bar: 'a'}};
|
|
setProperty(object, 'foo.bar', 'b');
|
|
console.log(object);
|
|
//=> {foo: {bar: 'b'}}
|
|
|
|
const foo = setProperty({}, 'foo.bar', 'c');
|
|
console.log(foo);
|
|
//=> {foo: {bar: 'c'}}
|
|
|
|
setProperty(object, 'foo.baz', 'x');
|
|
console.log(object);
|
|
//=> {foo: {bar: 'b', baz: 'x'}}
|
|
|
|
setProperty(object, 'foo.biz[0]', 'a');
|
|
console.log(object);
|
|
//=> {foo: {bar: 'b', baz: 'x', biz: ['a']}}
|
|
|
|
setProperty(object, 'foo.items.0', 'first');
|
|
console.log(object);
|
|
//=> {foo: {bar: 'b', baz: 'x', biz: ['a'], items: ['first']}}
|
|
|
|
// Has
|
|
hasProperty({foo: {bar: 'unicorn'}}, 'foo.bar');
|
|
//=> true
|
|
|
|
// Deleter
|
|
const object = {foo: {bar: 'a'}};
|
|
deleteProperty(object, 'foo.bar');
|
|
console.log(object);
|
|
//=> {foo: {}}
|
|
|
|
object.foo.bar = {x: 'y', y: 'x'};
|
|
deleteProperty(object, 'foo.bar.x');
|
|
console.log(object);
|
|
//=> {foo: {bar: {y: 'x'}}}
|
|
```
|
|
|
|
### Array paths
|
|
|
|
For improved performance and interoperability with other libraries, you can also pass paths as arrays instead of strings. This avoids the overhead of parsing string paths.
|
|
|
|
```js
|
|
import {getProperty, setProperty} from 'dot-prop';
|
|
|
|
const object = {
|
|
users: [
|
|
{name: 'Alice', role: 'admin'},
|
|
{name: 'Bob', role: 'user'}
|
|
]
|
|
};
|
|
|
|
// Using array paths - no parsing overhead
|
|
getProperty(object, ['users', 0, 'name']);
|
|
//=> 'Alice'
|
|
|
|
setProperty(object, ['users', 1, 'role'], 'moderator');
|
|
console.log(object.users[1].role);
|
|
//=> 'moderator'
|
|
|
|
// Useful for interoperability with libraries that return paths as arrays
|
|
const pathFromOtherLib = ['users', 0, 'profile', 'settings'];
|
|
setProperty(object, pathFromOtherLib, {theme: 'dark'});
|
|
```
|
|
|
|
Array paths:
|
|
- Avoid the parse/stringify cycle when you already have path segments
|
|
- Work with all functions: `getProperty`, `setProperty`, `hasProperty`, `deleteProperty`
|
|
- Numeric strings are automatically normalized to numbers for simplicity
|
|
|
|
## API
|
|
|
|
### getProperty(object, path, defaultValue?)
|
|
|
|
Get the value of the property at the given path.
|
|
|
|
Returns the value if any.
|
|
|
|
### setProperty(object, path, value)
|
|
|
|
Set the property at the given path to the given value.
|
|
|
|
Returns the object.
|
|
|
|
### hasProperty(object, path)
|
|
|
|
Check whether the property at the given path exists.
|
|
|
|
Returns a boolean.
|
|
|
|
### deleteProperty(object, path)
|
|
|
|
Delete the property at the given path.
|
|
|
|
Returns a boolean of whether the property existed before being deleted.
|
|
|
|
### escapePath(path)
|
|
|
|
Escape special characters in a path. Useful for sanitizing user input.
|
|
|
|
```js
|
|
import {getProperty, escapePath} from 'dot-prop';
|
|
|
|
const object = {
|
|
foo: {
|
|
bar: '👸🏻 You found me Mario!',
|
|
},
|
|
'foo.bar' : '🍄 The princess is in another castle!',
|
|
};
|
|
const escapedPath = escapePath('foo.bar');
|
|
|
|
console.log(getProperty(object, escapedPath));
|
|
//=> '🍄 The princess is in another castle!'
|
|
```
|
|
|
|
### parsePath(path)
|
|
|
|
Parse a dot path into an array of path segments.
|
|
|
|
Returns an array of path segments where numbers represent array indices and strings represent object keys.
|
|
|
|
```js
|
|
import {parsePath} from 'dot-prop';
|
|
|
|
parsePath('foo.bar');
|
|
//=> ['foo', 'bar']
|
|
|
|
parsePath('foo[0].bar');
|
|
//=> ['foo', 0, 'bar']
|
|
|
|
parsePath('foo.0.bar');
|
|
//=> ['foo', 0, 'bar']
|
|
|
|
parsePath('foo\\.bar');
|
|
//=> ['foo.bar']
|
|
|
|
// Use case: Iterate over path segments to build up a nested object
|
|
const path = 'users[0].profile.settings.theme';
|
|
const segments = parsePath(path);
|
|
//=> ['users', 0, 'profile', 'settings', 'theme']
|
|
```
|
|
|
|
### stringifyPath(pathSegments, options?)
|
|
|
|
Convert an array of path segments back into a path string.
|
|
|
|
Returns a string path that can be used with other dot-prop functions.
|
|
|
|
```js
|
|
import {stringifyPath} from 'dot-prop';
|
|
|
|
stringifyPath(['foo', 'bar']);
|
|
//=> 'foo.bar'
|
|
|
|
stringifyPath(['foo', 0, 'bar']);
|
|
//=> 'foo[0].bar'
|
|
|
|
stringifyPath(['foo', '0', 'bar']);
|
|
//=> 'foo[0].bar'
|
|
|
|
// With preferDotForIndices option
|
|
stringifyPath(['foo', 0, 'bar'], {preferDotForIndices: true});
|
|
//=> 'foo.0.bar'
|
|
```
|
|
|
|
#### pathSegments
|
|
|
|
Type: `Array<string | number>`
|
|
|
|
Array of path segments where numbers represent array indices and strings represent object keys.
|
|
|
|
#### options
|
|
|
|
Type: `object`
|
|
|
|
##### preferDotForIndices
|
|
|
|
Type: `boolean`\
|
|
Default: `false`
|
|
|
|
When `true`, numeric indices will use dot notation instead of bracket notation when not the first segment.
|
|
|
|
### deepKeys(object)
|
|
|
|
Returns an array of every path. Non-empty plain objects and arrays are deeply recursed and are not themselves included.
|
|
|
|
This can be useful to help flatten an object for an API that only accepts key-value pairs or for a tagged template literal.
|
|
|
|
```js
|
|
import {getProperty, deepKeys} from 'dot-prop';
|
|
|
|
const user = {
|
|
name: {
|
|
first: 'Richie',
|
|
last: 'Bendall',
|
|
},
|
|
activeTasks: [],
|
|
currentProject: null
|
|
};
|
|
|
|
for (const property of deepKeys(user)) {
|
|
console.log(`${property}: ${getProperty(user, property)}`);
|
|
//=> name.first: Richie
|
|
//=> name.last: Bendall
|
|
//=> activeTasks: []
|
|
//=> currentProject: null
|
|
}
|
|
```
|
|
|
|
Sparse arrays are supported. In general, [avoid using sparse arrays](https://github.com/sindresorhus/dot-prop/issues/109#issuecomment-1614819869).
|
|
|
|
#### object
|
|
|
|
Type: `object | array`
|
|
|
|
Object or array to get, set, or delete the `path` value.
|
|
|
|
You are allowed to pass in `undefined` as the object to the `get` and `has` functions.
|
|
|
|
#### path
|
|
|
|
Type: `string | Array<string | number>`
|
|
|
|
Path of the property in the object.
|
|
|
|
**String paths**: Use `.` to separate each nested key. Use `\\.` if you have a `.` in the key. Array indices can be accessed using bracket notation (like `'users[0].name'`) or dot notation (like `'users.0.name'`). Both syntaxes are equivalent and will create arrays when setting values. Numeric strings in dot notation (like `'users.0.name'`) are automatically coerced to numbers.
|
|
|
|
**Array paths**: Pass an array of path segments for better performance and interoperability. Numbers create arrays (like `['users', 0, 'name']`). Numeric strings are normalized to numbers for simplicity. No parsing overhead.
|
|
|
|
The following path components are invalid and results in `undefined` being returned: `__proto__`, `prototype`, `constructor`.
|
|
|
|
#### value
|
|
|
|
Type: `unknown`
|
|
|
|
Value to set at `path`.
|
|
|
|
#### defaultValue
|
|
|
|
Type: `unknown`
|
|
|
|
Default value.
|
|
|
|
### unflatten(object)
|
|
|
|
Convert an object with dot paths into a nested object.
|
|
|
|
Uses the same path rules and escaping as the rest of the API.
|
|
|
|
```js
|
|
import {unflatten} from 'dot-prop';
|
|
|
|
const flat = {
|
|
'unicorn.name': 'Rainbow Dash',
|
|
'unicorn.color': '🦄',
|
|
'unicorn.treasures[0]': 'sparkles',
|
|
'unicorn.treasures[1]': 'glitter',
|
|
};
|
|
|
|
unflatten(flat);
|
|
/*
|
|
{
|
|
unicorn: {
|
|
name: 'Rainbow Dash',
|
|
color: '🦄',
|
|
treasures: ['sparkles', 'glitter']
|
|
}
|
|
}
|
|
*/
|
|
```
|