@mojule/json-pointer
v0.3.4
Published
JSON Pointer implementation and tools
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json-pointer
JSON Pointer implementation for mojule
Heavily based on jsonpointer, with
additional functions like flatten
, expand
, pointers
and glob
added
npm install @mojule/json-pointer
'use strict'
const pointer = require( '@mojule/json-pointer' )
const { get, set, compile, flatten, expand, pointers, glob } = pointer
const obj = {
a: 1,
b: [ 2, 3, 4 ]
}
const p = pointers( obj ) // [ '/', '/a', '/b', '/b/0', '/b/1', '/b/2' ]
const a = get( obj, '/a' ) ) // 1
const b0 = get( obj, '/b/0' ) // 2
const oldValue = set( obj, '/a', -1 ) // 1
set( obj, '/b/-', 5 ) // b is now [ 2, 3, 4, 5 ]
const compiled = compile( '/b/0' ) // [ '', 'b', '0' ]
set( obj, compiled, -2 ) // b is now [ -2, 3, 4, 5 ]
/*
{
'/a': -1,
'/b/0': -2,
'/b/1': 3,
'/b/2': 4,
'/b/3': 5
}
*/
const flat = flatten( obj )
// same as obj
const expanded = expand( flat )
const flat2 = {
'/c': 6
}
// adds values from flat2 to obj
expand( flat2, obj )
glob
glob
is just a thin wrapper over micromatch
The first argument is the JSON object or array (other values will return an empty array), and the remaining arguments are passed directly to micromatch
glob( source, patterns[, options] )
const obj = {
a: 1,
b: [ 2, 3, 4 ]
}
const properties = glob( obj, '/*' ) // [ 1, [ 2, 3, 4 ] ]
const subArr = glob( obj, '/b/[1-2]' ) // [ 3, 4 ]
Pointer Value Arrays
Some additional functions for diffing objects
TODO, document in more depth
'use strict'
const pointer = require( '@mojule/json-pointer' )
const {
flatten, expand, pointerValueArray, pointerValueArrayToPointerMap, diff,
newFromDiff, oldFromDiff, sortedPointerValues, globPointerValues
} = pointer
const obj = {
a: 1,
b: [ 2, 3 ]
}
/*
{
'/a': 1,
'/b/0': 2,
'/b/1": 3
}
*/
const pointerMap = flatten( obj )
/*
[
{ pointer: '/a', value: 1, order: 0 },
{ pointer: '/b/0', value: 2, order: 1 },
{ pointer: '/b/1', value: 3, order: 2 }
]
*/
const values = pointerValueArray( obj )
// same as pointerMap
const pointerMap2 = pointerValueArrayToPointerMap( values )
const leftObj = {
unchanged: [ [], {} ],
changed: 0,
unchangedArray: [ 1, 2, 3 ],
changedArray: [ 4, 5, 6 ],
moved: 7,
movedAndChanged: 8,
removed: 9
}
const rightObj = {
unchanged: [ [], {} ],
changed: 9,
unchangedArray: [ 1, 2, 3 ],
changedArray: [ 6, 4, 5 ],
movedAndChanged: 11,
moved: 7,
added: 8
}
/*
[
{ pointer: '/unchanged/0', value: [], order: 0 },
// etc...
]
*/
const left = pointerValueArray( flatten( leftObj ) )
const right = pointerValueArray( flatten( rightObj ) )
/*
note - if left or right are unsorted, diff will throw - you can call diff with
a third boolean argument set to true to explicity sort before diffing (false by
default for performance, because if you're just using the provided functions
they should always be sorted, the only time they'll be unsorted is if you're
modifying the pointer value arrays yourself) - or you can use
sortedPointerValues to sort them yourself
[
{ pointer: '/unchanged/0', value: [], order: 0 },
{ pointer: '/unchanged/1', value: {}, order: 1 },
{ pointer: '/changed', value: 0, order: 2, newValue: 9 },
{ pointer: '/unchangedArray/0', value: 1, order: 3 },
{ pointer: '/unchangedArray/1', value: 2, order: 4 },
{ pointer: '/unchangedArray/2', value: 3, order: 5 },
{ pointer: '/changedArray/0', value: 4, order: 6, newValue: 6 },
{ pointer: '/changedArray/1', value: 5, order: 7, newValue: 4 },
{ pointer: '/changedArray/2', value: 6, order: 8, newValue: 5 },
{ pointer: '/moved', value: 7, order: 9, newOrder: 10 },
{ pointer: '/movedAndChanged', value: 8, order: 10, newValue: 11, newOrder: 9 },
{ pointer: '/removed', value: 9, order: 11, delete: true },
{ pointer: '/added', value: 8, order: 11, add: true }
]
*/
const diffValues = diff( left, right )
const newPointerValues = newFromDiff( diffValues )
const oldPointerValues = oldFromDiff( diffValues )
// same as rightObj
const newObj = expand( pointerValueArrayToPointerMap( newPointerValues ) )
// same as leftObj
const oldObj = expand( pointerValueArrayToPointerMap( oldPointerValues ) )
// if you modified your pointer value array and it's out of order
const left2 = left.slice().reverse()
const sortedLeft2 = sortedPointerValues( left2 )
// filter the pointer values using glob
const filtered = globPointerValues( values, '/b/**' )