@jsonhero/parser

JSON Hero Parser

A parser that walks through a JSON file and for each value determines the path to it, the type and paths to any children. It also builds a model of the structure of the data.

How to install

npm install @jsonhero/parser

Getting started

Importing

You can require

const { parse } = require('@jsonhero/parser');

Or if you're using TypeScript:

import { parse } from '@jsonhero/parser';

How to parse

Sample object

Given the following JSON variable called employees

let employees = {
  people: [
    {
      name: 'Matt',
      age: 36,
    },
    {
      name: 'James',
      age: 39,
    },
  ],
  count: 2,
};

Parsing

You parse a JSON object like this:

let structure = parse(employees);

Values and Structure

There are two top-level objects called values and structure.

Values has details for every single value from the parsed object. Structure groups together details to represent the actual data structure.

They have the following properties for each element:

Key name	Description
path	A JSONHeroPath as a string that points to this value
name	The originally formatted name
displayName	A nicely formatted name
value	The value itself
type	A Type from JSON Hero's infer types package
children	Null or an array of string paths to child values

The output

This produces an object that looks like this:

{
  "values": {
    "rootPath": "$",
    "values": {
      "$": {
        "path": "$",
        "name": "Root",
        "displayName": "Root",
        "value": {
          "people": [
            { "name": "Matt", "age": 36 },
            { "name": "James", "age": 39 }
          ],
          "count": 2
        },
        "type": {
          "name": "object",
          "value": {
            "people": [
              { "name": "Matt", "age": 36 },
              { "name": "James", "age": 39 }
            ],
            "count": 2
          }
        },
        "children": ["$.people", "$.count"]
      },
      "$.people": {
        "path": "$.people",
        "name": "people",
        "displayName": "People",
        "value": [
          { "name": "Matt", "age": 36 },
          { "name": "James", "age": 39 }
        ],
        "type": {
          "name": "array",
          "value": [
            { "name": "Matt", "age": 36 },
            { "name": "James", "age": 39 }
          ]
        },
        "children": ["$.people.0", "$.people.1"]
      },
      "$.people.0": {
        "path": "$.people.0",
        "name": "people 0",
        "displayName": "People 0",
        "value": { "name": "Matt", "age": 36 },
        "type": { "name": "object", "value": { "name": "Matt", "age": 36 } },
        "children": ["$.people.0.name", "$.people.0.age"]
      },
      "$.people.0.name": {
        "path": "$.people.0.name",
        "name": "name",
        "displayName": "Name",
        "value": "Matt",
        "type": { "name": "string", "value": "Matt" },
        "children": null
      },
      "$.people.0.age": {
        "path": "$.people.0.age",
        "name": "age",
        "displayName": "Age",
        "value": 36,
        "type": { "name": "int", "value": 36 },
        "children": null
      },
      "$.people.1": {
        "path": "$.people.1",
        "name": "people 1",
        "displayName": "People 1",
        "value": { "name": "James", "age": 39 },
        "type": { "name": "object", "value": { "name": "James", "age": 39 } },
        "children": ["$.people.1.name", "$.people.1.age"]
      },
      "$.people.1.name": {
        "path": "$.people.1.name",
        "name": "name",
        "displayName": "Name",
        "value": "James",
        "type": { "name": "string", "value": "James" },
        "children": null
      },
      "$.people.1.age": {
        "path": "$.people.1.age",
        "name": "age",
        "displayName": "Age",
        "value": 39,
        "type": { "name": "int", "value": 39 },
        "children": null
      },
      "$.count": {
        "path": "$.count",
        "name": "count",
        "displayName": "Count",
        "value": 2,
        "type": { "name": "int", "value": 2 },
        "children": null
      }
    }
  },
  "structure": {
    "rootPath": "$",
    "values": {
      "$": {
        "path": "$",
        "name": "Root",
        "displayName": "Root",
        "type": {
          "name": "object",
          "value": {
            "people": [
              { "name": "Matt", "age": 36 },
              { "name": "James", "age": 39 }
            ],
            "count": 2
          }
        },
        "children": ["$.people", "$.count"]
      },
      "$.people": {
        "path": "$.people",
        "name": "people",
        "displayName": "People",
        "type": {
          "name": "array",
          "value": [
            { "name": "Matt", "age": 36 },
            { "name": "James", "age": 39 }
          ]
        },
        "children": ["$.people.*"]
      },
      "$.people.*": {
        "path": "$.people.*",
        "name": "people",
        "displayName": "People",
        "type": { "name": "object", "value": { "name": "Matt", "age": 36 } },
        "children": ["$.people.*.name", "$.people.*.age"]
      },
      "$.people.*.name": {
        "path": "$.people.*.name",
        "name": "name",
        "displayName": "Name",
        "type": { "name": "string", "value": "Matt" },
        "children": null
      },
      "$.people.*.age": {
        "path": "$.people.*.age",
        "name": "age",
        "displayName": "Age",
        "type": { "name": "int", "value": 36 },
        "children": null
      },
      "$.count": {
        "path": "$.count",
        "name": "count",
        "displayName": "Count",
        "type": { "name": "int", "value": 2 },
        "children": null
      }
    }
  }
}