nkduy-iframe v0.2.2

nkduy-iframe

A tiny WebWorker polyfill for the file:// protocol

Like pseudo-worker but using an iframe instead of XMLHTTPRequest. This polyfill should be mostly spec-compliant and supports importScripts. It should pretty much be a drop-in replacement, at least for modern browsers which include a constructable EventTarget and Promise.

Installation

npm install nkduy-iframe

Usage

You can use the polyfill from unpkg.com (recommended):

<script src="https://unpkg.com/nkduy-iframe/polyfill"></script>

... or include the polyfill in your Webpack build:

import "nkduy-iframe/polyfill"

... or use IFrameWorker programmatically:

import { IFrameWorker } from "nkduy-iframe"

The polyfill will automatically mount if the document is served via file://.

Caveats

In Worker scripts, importScripts is a synchronous operation which will wait for the script to be loaded and executed. While it's not possible to implement this behavior as part of an iframe, the importScripts function that is provided as part of this polyfill returns a Promise which can be awaited on. Since awaiting a non-Promise is a no-op, using await on importScripts will work in polyfilled and non-polyfilled environments.

Motivation

The main reason this polyfill exists is that some users of Docurial need to distribute their documentation as static HTML files and bundle it with their product. Users would browser the documentation locally, using the file:// protocol, which broke the search functionality of the documentation, as search is implemented as part of a web worker. This polyfill in combination with the localsearch plugin allows to use search on the file:// protocol.