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This is a modified fork to serve Hey API needs

JSON Schema $Ref Parser

Parse, Resolve, and Dereference JSON Schema $ref pointers

Installation

Install using npm:

npm install @hey-api/json-schema-ref-parser
yarn add @hey-api/json-schema-ref-parser
bun add @hey-api/json-schema-ref-parser

The Problem:

You've got a JSON Schema with $ref pointers to other files and/or URLs. Maybe you know all the referenced files ahead of time. Maybe you don't. Maybe some are local files, and others are remote URLs. Maybe they are a mix of JSON and YAML format. Maybe some of the files contain cross-references to each other.

{
  "definitions": {
    "person": {
      // references an external file
      "$ref": "schemas/people/Bruce-Wayne.json"
    },
    "place": {
      // references a sub-schema in an external file
      "$ref": "schemas/places.yaml#/definitions/Gotham-City"
    },
    "thing": {
      // references a URL
      "$ref": "http://wayne-enterprises.com/things/batmobile"
    },
    "color": {
      // references a value in an external file via an internal reference
      "$ref": "#/definitions/thing/properties/colors/black-as-the-night"
    }
  }
}

The Solution:

JSON Schema $Ref Parser is a full JSON Reference and JSON Pointer implementation that crawls even the most complex JSON Schemas and gives you simple, straightforward JavaScript objects.

  • Use JSON or YAML schemas — or even a mix of both!
  • Supports $ref pointers to external files and URLs, as well as custom sources such as databases
  • Can bundle multiple files into a single schema that only has internal $ref pointers
  • Can dereference your schema, producing a plain-old JavaScript object that's easy to work with
  • Supports circular references, nested references, back-references, and cross-references between files
  • Maintains object reference equality — $ref pointers to the same value always resolve to the same object instance
  • Compatible with Node LTS and beyond, and all major web browsers on Windows, Mac, and Linux

Example

import { $RefParser } from "@hey-api/json-schema-ref-parser";

try {
  const parser = new $RefParser();
  await parser.dereference({ pathOrUrlOrSchema: mySchema });
  console.log(parser.schema.definitions.person.properties.firstName);
} catch (err) {
  console.error(err);
}

New in this fork (@hey-api)

  • Multiple inputs with bundleMany: Merge and bundle several OpenAPI/JSON Schema inputs (files, URLs, or raw objects) into a single schema. Components are prefixed to avoid name collisions, paths are namespaced on conflict, and $refs are rewritten accordingly.
import { $RefParser } from "@hey-api/json-schema-ref-parser";

const parser = new $RefParser();
const merged = await parser.bundleMany({
  pathOrUrlOrSchemas: [
    "./specs/a.yaml",
    "https://example.com/b.yaml",
    { openapi: "3.1.0", info: { title: "Inline" }, paths: {} },
  ],
});

// merged.components.* will contain prefixed names like a_<name>, b_<name>, etc.
  • Dereference hooks: Fine-tune dereferencing with excludedPathMatcher(path) => boolean to skip subpaths and onDereference(path, value, parent, parentPropName) to observe replacements.
const parser = new $RefParser();
parser.options.dereference.excludedPathMatcher = (p) => p.includes("/example/");
parser.options.dereference.onDereference = (p, v) => {
  // inspect p / v as needed
};
await parser.dereference({ pathOrUrlOrSchema: "./openapi.yaml" });
  • Smart input resolution: You can pass a file path, URL, or raw schema object. If a raw schema includes $id, it is used as the base URL for resolving relative $refs.
await new $RefParser().bundle({
  pathOrUrlOrSchema: {
    $id: "https://api.example.com/openapi.json",
    openapi: "3.1.0",
    paths: {
      "/ping": { get: { responses: { 200: { description: "ok" } } } },
    },
  },
});

Polyfills

If you are using Node.js < 18, you'll need a polyfill for fetch, like node-fetch:

import fetch from "node-fetch";

globalThis.fetch = fetch;

Browser support

JSON Schema $Ref Parser supports recent versions of every major web browser. Older browsers may require Babel and/or polyfills.

To use JSON Schema $Ref Parser in a browser, you'll need to use a bundling tool such as Webpack, Rollup, Parcel, or Browserify. Some bundlers may require a bit of configuration, such as setting browser: true in rollup-plugin-resolve.

Webpack 5

Webpack 5 has dropped the default export of node core modules in favour of polyfills, you'll need to set them up yourself ( after npm-installing them ) Edit your webpack.config.js :

config.resolve.fallback = {
  path: require.resolve("path-browserify"),
  fs: require.resolve("browserify-fs"),
};

config.plugins.push(
  new webpack.ProvidePlugin({
    Buffer: ["buffer", "Buffer"],
  }),
);

Building/Testing

To build/test the project locally on your computer:

  1. Clone this repo
    git clone https://github.com/APIDevTools/json-schema-ref-parser.git

  2. Install dependencies
    yarn install

  3. Run the tests
    yarn test

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Parse, Resolve, and Dereference JSON Schema $ref pointers in Node and browsers

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  • JavaScript 1.7%