Web Extension Shim

This repository contains a JavaScript shim (polyfill) for some Chrome Extension API calls.

Background

Online and mobile news consumption leaves digital traces that are used to personalize news supply, possibly creating filter bubbles where people are exposed to a low diversity of issues and perspectives that match their preferences. The JEDS Filter Bubble project aims to understand the filter bubble effect by performing deep semantic analyses on mobile news consumption traces. This project is a collaboration between the VU, the UvA and NLeSC, lead by Wouter van Atteveldt.

Part of this project makes use of the Web Historian browser extension, developed by Ericka Menchen-Trevino. To use this extension, or any other extension which follows the WebExtensions API, as a standalone website, all chrome.* API calls must be intercepted and re-implemented. In general, this will not be possible for all API calls. The shim in this project implement a few of them.

Installation

Prerequisites

• Download the source code of the extension.
• Download WebExtensionShim.js into the same directory.

Setup the shim

• Add the shim to the main page of the extension by adding <script type="application/javascript" src="WebExtensionShim.js"></script> to the HEAD of the HTML page.

Setup JSON files

• If the extension uses the chrome.runtime.getManifest() function, the shim requires a JSON variable named manifestJson which contains the manifest data. Add this JSON variable to the file Manifest.js and add <script type="application/javascript" src="Manifest.js"></script> to the HEAD of the extension's main page.
• If the extension uses the chrome.i18n.getMessage() function, the shim requires a JSON variable named messagesJson which contains the messages data. Add this JSON variable to the file Messages.js and add <script type="application/javascript" src="Messages.js"></script> to the HEAD of the extension's main page.
• If the extension uses any of the chrome.history.* functions, the shim requires two JSON variables named historyItemsJson and visitItemsJson which contain the browser history data. Add these JSON variables to the file HistoryItems.js and VisitItems.js and add <script type="application/javascript" src="HistoryItems.js"></script> and <script type="application/javascript" src="VisitItems.js"></script> to the HEAD of the extension's main page.

Repository content

WebExtensionShim.js

The Javascript file WebExtensionShim.js contains the shim.