Implement a PlatformInfo class for web ext

Author: brizental

src/platform_info/index.ts

@@ -0,0 +1,69 @@
+/* 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/. */
+
+// Must be up to date with https://github.com/mozilla/glean/blob/main/glean-core/src/system.rs
+export const enum KnownOperatingSystems {
+  Android = "Android",
+  iOS = "iOS",
+  Linux = "Linux",
+  MacOS = "Darwin",
+  Windows = "Windows",
+  FreeBSD = "FreeBSD",
+  NetBSD = "NetBSD",
+  OpenBSD = "OpenBSD",
+  Solaris = "Solaris",
+  // ChromeOS is not listed in the Glean SDK because it is not a possibility there.
+  ChromeOS = "ChromeOS",
+  Unknown = "Unknown",
+}
+
+export interface PlatformInfo {
+  /**
+   * Gets and returns the current OS system.
+   *
+   * @returns The current OS.
+   */
+  os(): Promise<KnownOperatingSystems>;
+
+  /**
+   * Gets and returns the current OS system version.
+   *
+   * @returns The current OS version.
+   */
+  osVersion(): Promise<string>;
+
+  /**
+   * Gets and returnst the current system architecture.
+   *
+   * @returns The current system architecture.
+   */
+  arch(): Promise<string>;
+
+  /**
+   * Gets and returnst the current system / browser locale.
+   *
+   * @returns The current system / browser locale.
+   */
+  locale(): Promise<string>;
+}
+
+// Default export for tests sake.
+const MockPlatformInfo: PlatformInfo = {
+  os(): Promise<KnownOperatingSystems> {
+    return Promise.resolve(KnownOperatingSystems.Unknown);
+  },
+
+  osVersion(): Promise<string> {
+    return Promise.resolve("Unknown");
+  },
+
+  arch(): Promise<string> {
+    return Promise.resolve("Unknown");
+  },
+
+  locale(): Promise<string> {
+    return Promise.resolve("Unknown");
+  },
+};
+export default MockPlatformInfo;

src/platform_info/webext.ts

@@ -0,0 +1,47 @@
+/* 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/. */
+
+import { PlatformInfo, KnownOperatingSystems } from "./index";
+
+const WebExtPlatformInfo: PlatformInfo = {
+  async os(): Promise<KnownOperatingSystems> {
+    // Possible values are listed in https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/PlatformOs
+    const platformInfo = await browser.runtime.getPlatformInfo();
+    switch(platformInfo.os) {
+    case "mac":
+      return KnownOperatingSystems.MacOS;
+    case "win":
+      return KnownOperatingSystems.Windows;
+    case "android":
+      return KnownOperatingSystems.Android;
+    case "cros":
+      return KnownOperatingSystems.ChromeOS;
+    case "linux":
+      return KnownOperatingSystems.Linux;
+    case "openbsd":
+      return KnownOperatingSystems.OpenBSD;
+    default:
+      return KnownOperatingSystems.Unknown;
+    }
+  },
+
+  async osVersion(): Promise<string> {
+    // The only way I found to extract osVersion from the browser was through the userAgent string
+    // and that is unreliable enought that I would rather not do it.
+    //
+    // For web extensions, browser type and version are more important anyways.
+    return Promise.resolve("Unknown");
+  },
+
+  async arch(): Promise<string> {
+    const platformInfo = await browser.runtime.getPlatformInfo();
+    // Possible values are: "arm", "x86-32", "x86-64"
+    return platformInfo.arch;
+  },
+
+  async locale(): Promise<string> {
+    return Promise.resolve(navigator.language || "Unknown");
+  }
+};
+export default WebExtPlatformInfo;

webpack.config.webext.js

@@ -18,6 +18,7 @@ module.exports = {
     ...baseConfig.resolve,
     alias: {
       "storage/persistent": path.resolve(__dirname, "src/storage/persistent/webext"),
+      "platform_info": path.resolve(__dirname, "src/platform_info/webext"),
     }
   }
 };