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dfahlander / typeson-registry

The type registry for typeson
MIT License
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typeson-registry

The type registry for typeson.

See below for notes on these types and presets.

Note that some types will require polyfills in Node such as via jsdom. See the testing environment of test/test.js for some examples.

Installation

Note that for Node.js, to use the file or blob types (or the filelist type or structuredCloning and structuredCloningThrowing presets which include them), you will need a polyfill for Blob or File, respectively, as well as FileReader and URL.createObjectURL (and a polyfill for URL if you are using Node < 10.0.0 or an older browser). Note that our URL.createObjectURL polyfill expects a global XMLHttpRequest and location.href predefined before it as well (and one which can handle data: URLs). For Node, you can add it like this:

const url = require('url'); // This line only needed to support Node < 10.0.0
const {createObjectURL} = require('typeson-registry/polyfills/createObjectURL.umd.cjs');

const URL = url.Url; // This line only needed to support Node < 10.0.0
URL.createObjectURL = createObjectURL;

We have not added jsdom as a dependency, but it is required if this polyfill is used.

Besides the polyfills for file or blob, the structuredCloningThrowing preset also needs a global DOMException polyfill.

The filelist type, in addition to the polyfills for file, will need a FileList polyfill (including a FileList string tag).

The imagebitmap type requires a global createImageBitmap polyfill (and an ImageBitmap polyfill (including an ImageBitmap string tag).

The imagedata type requires a global ImageData polyfill (including an ImageData string tag).

You may wish to see our test-environment.js file for how some polyfilling may be done (largely using jsdom).

Building files from Git clone (as opposed to npm installs)

If you have cloned the repo (and not the npm package), you must run npm install to get the devDependencies and then run npm run rollup to get the individual browser scripts built locally (into dist) or to get index.js to be rebuilt based on existing presets and types).

Usage (Pre-rollup in Node or browser)

import {Typeson, date, error, regexp, typedArrays} from 'typeson-registry';

const TSON = new Typeson().register([
    date,
    error,
    regexp,
    typedArrays
    // ...
]);

const tson = TSON.stringify({
    Hello: 'world',
    date: new Date(),
    error: new Error('test'),
    inner: {
        x: /foo/gui,
        bin: new Uint8Array(64)
    }
}, null, 2);

console.log(tson);
/* Output:

{
  "Hello": "world",
  "date": 1464049031538,
  "error": {
    "name": "Error",
    "message": "test"
  },
  "inner": {
    "x": {
      "source": "foo",
      "flags": "gi"
    },
    "bin": "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=="
  },
  "$types": {
    "date": "Date",
    "error": "Error",
    "inner.x": "RegExp",
    "inner.bin": "Uint8Array"
  }
}
*/

const parsedBack = TSON.parse(tson);

console.log(parsedBack.date instanceof Date);
console.log(parsedBack.inner.bin instanceof Uint8Array);

Usage (Node without own Rollup)

const {Typeson, builtin} = require('typeson-registry');

const tson = new Typeson().register([
    builtin
]);

Usage (import in supporting browsers without own Rollup)

<script type="module">

import {Typeson, builtin} from './node_modules/typeson-registry/dist/index.js';

const TSON = new Typeson().register([
    builtin
]);
</script>

Usage (with plain script tags without own Rollup)

All types and presets under dist/ are UMD modules so you could also require them as AMD modules with requirejs if you prefer.

<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/typeson/dist/typeson.umd.min.js"></script>
    <script src="https://unpkg.com/typeson-registry/dist/presets/builtin.umd.cjs"></script>
    <script>

    const TSON = new Typeson().register(builtin);
    const tson = TSON.stringify({
        Hello: 'world',
        date: new Date(),
        error: new Error('err'),
        inner: {
            x: /foo/giu,
            bin: new Uint8Array(64)
        }
    }, null, 2);

    alert(tson);
    /* Alerts:

    {
      "Hello": "world",
      "date": 1464049031538,
      "error": {
        "name": "Error",
        "message": "err"
      },
      "inner": {
        "x": {
          "source": "foo",
          "flags": "gi"
        },
        "bin": "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=="
      },
      "$types": {
        "date": "Date",
        "error": "Error",
        "inner.x": "RegExp",
        "inner.bin": "Uint8Array"
      }
    }
    */

    </script>
  </head>
</html>

Notes on types and presets

Note that the type name corresponds to the file name in the following manner:

  1. Genuine separate words are camel-cased in the type name but hyphenated in the file name (e.g., negativeInfinity and negativity-infinity.js); names whose original API is camel-cased are not hyphenated, however (e.g., arraybuffer and arraybuffer.js given ArrayBuffer).
  2. All other portions of names are lower-cased (e.g., date and date.js).
  3. Type names that would clash with existing objects when exported (even after lower-casing) must have a separate, preferably abbreviated form (e.g., the type and preset undef and undef.js was necessary for undefined)
  4. Type names which are not allowed as ES6 exports (e.g., periods in Intl types are now removed: Intl.Collator -> IntlCollator)
  5. Type names should indicate the singular (e.g., userObject) except for files containing multiple related exports (e.g., errors, typed-arrays, and typed-arrays-socketio.js); files with multiple exports whose extra exports are incidental (e.g., filelist) do not need a plural.

Types

Presets

Functions (support not included)

If you are looking for a way to resurrect functions, you can use the following, but please bear in mind that it uses eval which is prohibited by some Content Security Policies (CSP) (so we are not packaging it with our builds), that it is unsafe, and also that the function might not behave deterministically when revived (e.g., if the function were provided from another context).

const functionType = {functionType: [
    function (x) { return typeof x === 'function'; },
    function (funcType) { return '(' + funcType.toString() + ')'; },
    // eslint-disable-next-line no-eval -- Demonstrating
    function (o) { return eval(o); }
]};

const typeson = new Typeson().register(functionType);
const tson = typeson.stringify(function () { return 'abc'; });
const back = typeson.parse(tson);
back(); // 'abc'

Development

node-canvas is used to test ImageData.

Be sure to follow the installation steps.

On Windows, besides following the Windows installation steps, this helped complete the installation. If you need to have it rebuilt, you can run npm i inside of the node_modules/canvas directory.

These steps were also necessary but you can run npm run windows after install to get these steps applied. These are the only steps which should need to be re-run if you have deleted your local node-canvas copy.

See also