Issue mozilla-mobile#2080: Extract website icon resources via WebExte…

…nsion.

components/browser/icons/build.gradle

@@ -23,6 +23,7 @@ android {
 
 dependencies {
     implementation project(':support-ktx')
+    implementation project(':concept-engine')
 
     implementation Dependencies.kotlin_stdlib
     implementation Dependencies.kotlin_coroutines

components/browser/icons/src/main/assets/extensions/browser-icons/icons.js

@@ -0,0 +1,64 @@
+/* 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/. */
+
+ /*
+  * This web extension looks for known icon tags, collects URLs and available
+  * meta data (e.g. sizes) and passes that to the app code.
+  */
+
+function collect_link_icons(icons, rel) {
+    document.querySelectorAll('link[rel="' + rel + '"]').forEach(
+        function(currentValue, currentIndex, listObj) {
+            icons.push({
+                'type': rel,
+                'href': currentValue.href,
+                'sizes': currentValue.sizes
+            });
+    })
+}
+
+function collect_meta_property_icons(icons, property) {
+    document.querySelectorAll('meta[property="' + property + '"]').forEach(
+        function(currentValue, currentIndex, listObj) {
+            icons.push({
+                'type': property,
+                'href': currentValue.content
+            })
+        }
+    )
+}
+
+function collect_meta_name_icons(icons, name) {
+    document.querySelectorAll('meta[name="' + name + '"]').forEach(
+        function(currentValue, currentIndex, listObj) {
+            icons.push({
+                'type': name,
+                'href': currentValue.content
+            })
+        }
+    )
+}
+
+let icons = [];
+
+collect_link_icons(icons, 'icon');
+collect_link_icons(icons, 'shortcut icon');
+collect_link_icons(icons, 'fluid-icon')
+collect_link_icons(icons, 'apple-touch-icon')
+collect_link_icons(icons, 'image_src')
+collect_link_icons(icons, 'apple-touch-icon image_src')
+collect_link_icons(icons, 'apple-touch-icon-precomposed')
+
+collect_meta_property_icons(icons, 'og:image')
+collect_meta_property_icons(icons, 'og:image:url')
+collect_meta_property_icons(icons, 'og:image:secure_url')
+
+collect_meta_name_icons(icons, 'twitter:image')
+collect_meta_name_icons(icons, 'msapplication-TileImage')
+
+// TODO: For now we are just logging the icons we found here. We need the Messaging API
+//       to actually be able to pass them to the Android world.
+// https://github.com/mozilla-mobile/android-components/issues/2243
+// https://bugzilla.mozilla.org/show_bug.cgi?id=1518843
+console.log("browser-icons: (" + icons.length + ")", document.location.href, icons)

components/browser/icons/src/main/assets/extensions/browser-icons/manifest.json

@@ -0,0 +1,12 @@
+{
+  "manifest_version": 2,
+  "name": "Mozilla Android Components - Browser Icons",
+  "version": "1.0",
+  "content_scripts": [
+    {
+      "matches": ["*://*/*"],
+      "js": ["icons.js"],
+      "run_at": "document_end"
+    }
+  ]
+}

components/browser/icons/src/main/java/mozilla/components/browser/icons/BrowserIcons.kt

@@ -12,6 +12,9 @@ import kotlinx.coroutines.asCoroutineDispatcher
 import kotlinx.coroutines.async
 import mozilla.components.browser.icons.generator.DefaultIconGenerator
 import mozilla.components.browser.icons.generator.IconGenerator
+import mozilla.components.concept.engine.Engine
+import mozilla.components.concept.engine.webextension.WebExtension
+import mozilla.components.support.base.log.logger.Logger
 import java.util.concurrent.Executors
 
 // Number of worker threads we are using internally.
@@ -34,4 +37,20 @@ class BrowserIcons(
         // For now we only generate an icon.
         generator.generate(context, request)
     }
+
+    /**
+     * Installs the "icons" extension in the engine in order to dynamically load icons for loaded websites.
+     */
+    fun install(engine: Engine) {
+        engine.installWebExtension(
+            WebExtension(
+                id = "browser-icons",
+                url = "resource://android/assets/extensions/browser-icons/"),
+            onSuccess = {
+                Logger.debug("Installed browser-icons extension")
+            },
+            onError = { _, throwable ->
+                Logger.error("Could not install browser-icons extension", throwable)
+            })
+    }
 }

samples/browser/src/geckoNightly/java/org/mozilla/samples/browser/Components.kt

@@ -18,6 +18,8 @@ class Components(private val applicationContext: Context) : DefaultComponents(ap
             installWebExtension(WebExtension("mozac-borderify", "resource://android/assets/extensions/borderify/")) {
                 ext, throwable -> Log.log(Log.Priority.ERROR, "SampleBrowser", throwable, "Failed to install ${ext.id}")
             }
+
+            icons.install(this)
         }
     }
 }