make permissions work for firefox

src/webex/compat.ts

@@ -33,3 +33,53 @@ export function isFirefox(): boolean {
 export function isNode(): boolean {
   return typeof process !== "undefined" && process.release.name === "node";
 }
+
+/**
+ * Compatibility API that works on multiple browsers.
+ */
+export interface CrossBrowserPermissionsApi {
+  contains(
+    permissions: chrome.permissions.Permissions,
+    callback: (result: boolean) => void,
+  ): void;
+
+  addPermissionsListener(
+    callback: (permissions: chrome.permissions.Permissions) => void,
+  ): void;
+
+  request(
+    permissions: chrome.permissions.Permissions,
+    callback?: (granted: boolean) => void,
+  ): void;
+
+  remove(
+    permissions: chrome.permissions.Permissions,
+    callback?: (removed: boolean) => void,
+  ): void;
+}
+
+export function getPermissionsApi(): CrossBrowserPermissionsApi {
+  const myBrowser = (globalThis as any).browser;
+  if (
+    typeof myBrowser === "object" &&
+    typeof myBrowser.permissions === "object"
+  ) {
+    return {
+      addPermissionsListener: () => {
+        // Not supported yet.
+      },
+      contains: myBrowser.permissions.contains,
+      request: myBrowser.permissions.request,
+      remove: myBrowser.permissions.remove,
+    };
+  } else {
+    return {
+      addPermissionsListener: chrome.permissions.onAdded.addListener.bind(
+        chrome.permissions.onAdded,
+      ),
+      contains: chrome.permissions.contains,
+      request: chrome.permissions.request,
+      remove: chrome.permissions.remove,
+    };
+  }
+}

src/webex/pages/welcome.tsx

@@ -25,6 +25,8 @@ import { getDiagnostics } from "../wxApi";
 import { PageLink } from "../renderHtml";
 import { WalletDiagnostics } from "../../types/walletTypes";
 import * as wxApi from "../wxApi";
+import { getPermissionsApi } from "../compat";
+import { extendedPermissions } from "../permissions";
 
 function Diagnostics(): JSX.Element | null {
   const [timedOut, setTimedOut] = useState(false);
@@ -97,22 +99,51 @@ function Diagnostics(): JSX.Element | null {
 }
 
 export function PermissionsCheckbox(): JSX.Element {
-  const [extendedPermissions, setExtendedPermissions] = useState(false);
-  async function handleExtendedPerm(newVal: boolean): Promise<void> {
-    const res = await wxApi.setExtendedPermissions(newVal);
-    setExtendedPermissions(res.newValue);
+  const [extendedPermissionsEnabled, setExtendedPermissionsEnabled] = useState(
+    false,
+  );
+  async function handleExtendedPerm(requestedVal: boolean): Promise<void> {
+    let nextVal: boolean | undefined;
+    if (requestedVal) {
+      const granted = await new Promise<boolean>((resolve, reject) => {
+        // We set permissions here, since apparently FF wants this to be done
+        // as the result of an input event ...
+        getPermissionsApi().request(
+          extendedPermissions,
+          (granted: boolean) => {
+            if (chrome.runtime.lastError) {
+              console.error("error requesting permissions");
+              console.error(chrome.runtime.lastError);
+              reject(chrome.runtime.lastError);
+              return;
+            }
+            console.log("permissions granted:", granted);
+            resolve(granted);
+          },
+        );
+      });
+      const res = await wxApi.setExtendedPermissions(granted);
+      console.log(res);
+      nextVal = res.newValue;
+    } else {
+      const res = await wxApi.setExtendedPermissions(false);
+      console.log(res);
+      nextVal = res.newValue;
+    }
+    console.log("new permissions applied:", nextVal);
+    setExtendedPermissionsEnabled(nextVal ?? false);
   }
   useEffect(() => {
     async function getExtendedPermValue(): Promise<void> {
       const res = await wxApi.getExtendedPermissions();
-      setExtendedPermissions(res.newValue);
+      setExtendedPermissionsEnabled(res.newValue);
     }
     getExtendedPermValue();
   });
   return (
     <div>
       <input
-        checked={extendedPermissions}
+        checked={extendedPermissionsEnabled}
         onChange={(x) => handleExtendedPerm(x.target.checked)}
         type="checkbox"
         id="checkbox-perm"

src/webex/permissions.ts

@@ -0,0 +1,20 @@
+/*
+ This file is part of GNU Taler
+ (C) 2020 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+export const extendedPermissions = {
+  permissions: ["webRequest", "webRequestBlocking"],
+  origins: ["http://*/*", "https://*/*"],
+};

src/webex/wxBackend.ts

@@ -40,11 +40,12 @@ import { BrowserHttpLib } from "../util/http";
 import { OpenedPromise, openPromise } from "../util/promiseUtils";
 import { classifyTalerUri, TalerUriType } from "../util/taleruri";
 import { Wallet } from "../wallet";
-import { isFirefox } from "./compat";
+import { isFirefox, getPermissionsApi } from "./compat";
 import { MessageType } from "./messages";
 import * as wxApi from "./wxApi";
 import MessageSender = chrome.runtime.MessageSender;
 import { Database } from "../util/query";
+import { extendedPermissions } from "./permissions";
 
 const NeedsWallet = Symbol("NeedsWallet");
 
@@ -63,11 +64,6 @@ let outdatedDbVersion: number | undefined;
 
 const walletInit: OpenedPromise<void> = openPromise<void>();
 
-const extendedPermissions = {
-  permissions: ["webRequest", "webRequestBlocking"],
-  origins: ["http://*/*", "https://*/*"],
-};
-
 const notificationPorts: chrome.runtime.Port[] = [];
 
 async function handleMessage(
@@ -216,7 +212,7 @@ async function handleMessage(
       if (!proposalId) {
         throw Error("proposalId missing");
       }
-      if (typeof proposalId !== "string")  {
+      if (typeof proposalId !== "string") {
         throw Error("proposalId must be a string");
       }
       return needsWallet().getPurchaseDetails(proposalId);
@@ -294,26 +290,13 @@ async function handleMessage(
       return needsWallet().preparePayForUri(detail.talerPayUri);
     case "set-extended-permissions": {
       const newVal = detail.value;
+      console.log("new extended permissions value", newVal);
       if (newVal) {
-        const res = await new Promise((resolve, reject) => {
-          chrome.permissions.request(
-            extendedPermissions,
-            (granted: boolean) => {
-              console.log("permissions granted:", granted);
-              if (chrome.runtime.lastError) {
-                console.error(chrome.runtime.lastError);
-              }
-              resolve(granted);
-            },
-          );
-        });
-        if (res) {
-          setupHeaderListener();
-        }
-        return { newValue: res };
+        setupHeaderListener();
+        return { newValue: true };
       } else {
         await new Promise((resolve, reject) => {
-          chrome.permissions.remove(extendedPermissions, (rem) => {
+          getPermissionsApi().remove(extendedPermissions, (rem) => {
             console.log("permissions removed:", rem);
             resolve();
           });
@@ -323,7 +306,7 @@ async function handleMessage(
     }
     case "get-extended-permissions": {
       const res = await new Promise((resolve, reject) => {
-        chrome.permissions.contains(extendedPermissions, (result: boolean) => {
+        getPermissionsApi().contains(extendedPermissions, (result: boolean) => {
           resolve(result);
         });
       });
@@ -590,7 +573,7 @@ function headerListener(
 function setupHeaderListener(): void {
   console.log("setting up header listener");
   // Handlers for catching HTTP requests
-  chrome.permissions.contains(extendedPermissions, (result: boolean) => {
+  getPermissionsApi().contains(extendedPermissions, (result: boolean) => {
     if (
       chrome.webRequest.onHeadersReceived &&
       chrome.webRequest.onHeadersReceived.hasListener(headerListener)
@@ -644,9 +627,15 @@ export async function wxMain(): Promise<void> {
     });
   });
 
-  setupHeaderListener();
+  try {
+    setupHeaderListener();
+  } catch (e) {
+    console.log(e);
+  }
 
-  chrome.permissions.onAdded.addListener((perm) => {
+  // On platforms that support it, also listen to external
+  // modification of permissions.
+  getPermissionsApi().addPermissionsListener((perm) => {
     if (chrome.runtime.lastError) {
       console.error(chrome.runtime.lastError);
       return;