Tool for populating JSON data with infinitely recursive circular references. Sort of like Falcor, but for plain JSON. It uses Proxy to lazily resolve relations where supported, otherwise there's a polyfill that uses an eager Object.assign approach (slow and very memory intensive if you populate more than a few levels - it's really just there for symbolic backwards compatibility)
Populating by naming convention:
/**
* Import lib
*/
const { populateByConvention } = require('json-populate');
/**
* Example data
*/
const stories = [
{
type: 'story',
id: 'story-1',
author: {
person: 'person-1',
},
},
{
type: 'story',
id: 'story-2',
author: {
person: 'person-2',
},
},
];
const people = [
{
type: 'person',
id: 'person-1',
name: 'John Storywriter',
authored: {
stories: ['story-1'],
},
likes: {
stories: [
'story-1',
'story-2',
],
}
},
{
type: 'person',
id: 'person-2',
name: 'Peter Telltale',
authored: {
stories: ['story-2'],
},
likes: {
stories: [
'story-1',
'story-2',
],
}
}
];
/**
* Consolidate the collections into a "graph"
*/
const graph = { people, stories };
/**
* Choose an entry point to the graph
*/
const entry = people[0];
/**
* Create a populated entry point resolved against the graph with a specified depth
*/
const populatedItem = populateByConvention(2, graph, entry);
/**
* Result
*/
console.log(JSON.stringify(populatedItem, null, 2));
/**
* {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": {
* "stories": [
* {
* "type": "story",
* "id": "story-1",
* "author": {
* "person": {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": {
* "stories": [
* "story-1"
* ]
* },
* "likes": {
* "stories": [
* "story-1",
* "story-2"
* ]
* }
* }
* }
* }
* ]
* },
* "likes": {
* "stories": [
* {
* "type": "story",
* "id": "story-1",
* "author": {
* "person": {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": {
* "stories": [
* "story-1"
* ]
* },
* "likes": {
* "stories": [
* "story-1",
* "story-2"
* ]
* }
* }
* }
* },
* {
* "type": "story",
* "id": "story-2",
* "author": {
* "person": {
* "type": "person",
* "id": "person-2",
* "name": "Peter Telltale",
* "authored": {
* "stories": [
* "story-2"
* ]
* },
* "likes": {
* "stories": [
* "story-1",
* "story-2"
* ]
* }
* }
* }
* }
* ]
* }
* }
*/Populating by explicit reference:
/**
* Import lib
*/
const { populateByReference } = require('json-populate');
/**
* Example data
*/
const stories = [
{
type: 'story',
id: 'story-1',
author: { $ref: 'people', id: 'person-1' }
},
{
type: 'story',
id: 'story-2',
author: { $ref: 'people', id: 'person-2' }
},
];
const people = [
{
type: 'person',
id: 'person-1',
name: 'John Storywriter',
authored: [
{ $ref: 'stories', id: 'story-1' },
],
likes: [
{ $ref: 'stories', id: 'story-1' },
{ $ref: 'stories', id: 'story-2' },
],
},
{
type: 'person',
id: 'person-2',
name: 'Peter Telltale',
authored: [
{ $ref: 'stories', id: 'story-2' },
],
likes: [
{ $ref: 'stories', id: 'story-1' },
{ $ref: 'stories', id: 'story-2' },
],
}
];
/**
* Consolidate the collections into a "graph"
*/
const graph = { people, stories };
/**
* Choose an entry point to the graph
*/
const entry = people[0];
/**
* Create a populated entry point resolved against the graph with a specified depth
*/
const populatedItem = populateByReference(2, graph, entry);
/**
* Result
*/
console.log(JSON.stringify(populatedItem, null, 2));
/**
* {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": [
* {
* "type": "story",
* "id": "story-1",
* "author": {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": [
* {
* "$ref": "stories",
* "id": "story-1"
* }
* ],
* "likes": [
* {
* "$ref": "stories",
* "id": "story-1"
* },
* {
* "$ref": "stories",
* "id": "story-2"
* }
* ]
* }
* }
* ],
* "likes": [
* {
* "type": "story",
* "id": "story-1",
* "author": {
* "type": "person",
* "id": "person-1",
* "name": "John Storywriter",
* "authored": [
* {
* "$ref": "stories",
* "id": "story-1"
* }
* ],
* "likes": [
* {
* "$ref": "stories",
* "id": "story-1"
* },
* {
* "$ref": "stories",
* "id": "story-2"
* }
* ]
* }
* },
* {
* "type": "story",
* "id": "story-2",
* "author": {
* "type": "person",
* "id": "person-2",
* "name": "Peter Telltale",
* "authored": [
* {
* "$ref": "stories",
* "id": "story-2"
* }
* ],
* "likes": [
* {
* "$ref": "stories",
* "id": "story-1"
* },
* {
* "$ref": "stories",
* "id": "story-2"
* }
* ]
* }
* }
* ]
* }
*/