✨ Implement nsIAboutModule (#45)

apps/content/webpack.config.js

@@ -13,7 +13,6 @@ import WebpackLicensePlugin from 'webpack-license-plugin'
 
 const HTML_TEMPLATE_FILE = './src/index.html'
 
-const getDistFile = (file) => resolve('dist', file)
 const absolutePackage = (file) => resolve('node_modules', file)
 
 /**

apps/misc/static/defaults/pref/prefs.js

@@ -108,6 +108,10 @@ pref('browser.download.clearHistoryOnDelete', 0);
 // We do this because we want page actions etc. to have color schemes
 pref('svg.context-properties.content.enabled', true);
 
+// Security page preferences
+// This requires our own testing server, which we don't have
+pref('security.certerrors.mitm.priming.enabled', true);
+
 // =============================================================================
 // Multithreading
 

apps/modules/lib/AboutRedirector.sys.mjs

@@ -0,0 +1,108 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// @ts-check
+/// <reference types="@browser/link" />
+
+/**
+ * Based on Thunderbird's module with the same name
+ * {@link https://searchfox.org/comm-central/source/mail/components/AboutRedirector.jsm}
+ */
+export class AboutRedirector {
+  QueryInterface = ChromeUtils.generateQI(['nsIAboutModule'])
+
+  /**
+   * @type {Record<string, {url: string, flags: number}>}
+   * @private
+   */
+  redirectMap = {
+    certerror: {
+      url: 'chrome://global/content/aboutNetError.xhtml',
+      flags:
+        Ci.nsIAboutModule.URI_SAFE_FOR_UNTRUSTED_CONTENT |
+        Ci.nsIAboutModule.URI_CAN_LOAD_IN_CHILD |
+        Ci.nsIAboutModule.ALLOW_SCRIPT |
+        Ci.nsIAboutModule.HIDE_FROM_ABOUTABOUT,
+    },
+    tests: {
+      url: 'chrome://browser/content/tests/index.html',
+      flags: Ci.nsIAboutModule.ALLOW_SCRIPT,
+    },
+  }
+
+  /**
+   * Filters out hashes and query strings from the about url, returning just the name
+   * @private
+   * @param {nsIURIType} uri
+   * @returns {string}
+   */
+  getRedirectName({ pathQueryRef }) {
+    const [name] = /[^?#]+/.exec(pathQueryRef) || ['invalid']
+    return name.toLowerCase()
+  }
+
+  /**
+   * @private
+   * @param {string} name The name of the missing page
+   * @returns {never}
+   */
+  notRegistered(name) {
+    throw new Error(`about:${name} was not registered with AboutRedirector`)
+  }
+
+  /**
+   * @param {nsIURIType} uri
+   * @param {nsILoadInfoType} loadInfo
+   * @returns {nsIChannelType}
+   */
+  newChannel(uri, loadInfo) {
+    const redirectName = this.getRedirectName(uri)
+    const redirect = this.redirectMap[redirectName]
+    if (!redirect) this.notRegistered(redirectName)
+
+    const redirectUri = Services.io.newURI(redirect.url)
+    const channel = Services.io.newChannelFromURIWithLoadInfo(
+      redirectUri,
+      loadInfo,
+    )
+    channel.originalURI = uri
+
+    const safeForUntrustedContent =
+      redirect.flags & Ci.nsIAboutModule.URI_SAFE_FOR_UNTRUSTED_CONTENT
+    if (safeForUntrustedContent) {
+      channel.owner = Services.scriptSecurityManager.createContentPrincipal(
+        uri,
+        {},
+      )
+    }
+
+    return channel
+  }
+
+  /**
+   * Fetches some combination of flags for some `about:` url
+   * @param {nsIURIType} uri The url to get flags for
+   * @returns {number} The assigned flags
+   */
+  getURIFlags(uri) {
+    const redirectName = this.getRedirectName(uri)
+    const redirect = this.redirectMap[redirectName]
+    if (!redirect) this.notRegistered(redirectName)
+
+    return redirect.flags
+  }
+
+  /**
+   * Finds the uri for a paticular `about:` about
+   * @param {nsIURIType} uri The url to match
+   * @returns {nsIURIType} The page to redirect to
+   */
+  getChromeURI(uri) {
+    const redirectName = this.getRedirectName(uri)
+    const redirect = this.redirectMap[redirectName]
+    if (!redirect) this.notRegistered(redirectName)
+
+    return Services.io.newURI(redirect.url)
+  }
+}

docs/about-pages.md

@@ -0,0 +1,4 @@
+# Custom about pages
+
+1. You need to update the [runtime](https://github.com/pulse-browser/experiment-runtime/blob/main/src/quark-runtime/components/components.conf) component to include the contract `@mozilla.org/network/protocol/about;1?what=<page_name>`. You will need to wait for CI to build or use `rt:slink`
+2. Add your page to `redirectMap` inside of `AboutRedirector.sys.mjs`

libs/shared/src/utilities/svelte.ts

@@ -113,7 +113,6 @@ export function resolverStore<T>(
 export const dynamicStringPref =
   <T>(processor: (value: string) => T) =>
   (pref: string): Readable<T> => {
-    console.log('dynamicStringPref', pref)
     return readable(
       processor(Services.prefs.getStringPref(pref, '')),
       (set) => {