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|
/*
This file is part of GNU Taler
(C) 2022 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/>
*/
import {
Logger,
TalerErrorCode,
TalerUriAction,
TalerError,
parseTalerUri,
TalerUri,
stringifyTalerUri,
} from "@gnu-taler/taler-util";
import { WalletOperations } from "@gnu-taler/taler-wallet-core";
import { BackgroundOperations } from "../wxApi.js";
import {
BackgroundPlatformAPI,
CrossBrowserPermissionsApi,
ForegroundPlatformAPI,
MessageFromBackend,
MessageFromFrontend,
MessageResponse,
Permissions,
Settings,
defaultSettings,
} from "./api.js";
const api: BackgroundPlatformAPI & ForegroundPlatformAPI = {
isFirefox,
getSettingsFromStorage,
findTalerUriInActiveTab,
findTalerUriInClipboard,
getPermissionsApi,
getWalletWebExVersion,
listenToWalletBackground,
notifyWhenAppIsReady,
openWalletPage,
openWalletPageFromPopup,
openWalletURIFromPopup,
redirectTabToWalletPage,
registerAllIncomingConnections,
registerOnInstalled,
listenToAllChannels: listenToAllChannels as any,
registerReloadOnNewVersion,
sendMessageToAllChannels,
sendMessageToBackground,
useServiceWorkerAsBackgroundProcess,
keepAlive,
listenNetworkConnectionState,
};
export default api;
const logger = new Logger("chrome.ts");
async function getSettingsFromStorage(): Promise<Settings> {
const data = await chrome.storage.local.get("wallet-settings");
if (!data) return defaultSettings;
const settings = data["wallet-settings"];
if (!settings) return defaultSettings;
try {
const parsed = JSON.parse(settings);
return parsed;
} catch (e) {
return defaultSettings;
}
}
function keepAlive(callback: any): void {
if (extensionIsManifestV3()) {
chrome.alarms.create("wallet-worker", { periodInMinutes: 1 });
chrome.alarms.onAlarm.addListener((a) => {
logger.trace(`kee p alive alarm: ${a.name}`);
// callback()
});
// } else {
}
callback();
}
function isFirefox(): boolean {
return false;
}
// const hostPermissions = {
// permissions: ["webRequest"],
// origins: ["http://*/*", "https://*/*"],
// };
export function containsClipboardPermissions(): Promise<boolean> {
return new Promise((res, rej) => {
res(false);
// chrome.permissions.contains({ permissions: ["clipboardRead"] }, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
});
}
// export function containsHostPermissions(): Promise<boolean> {
// return new Promise((res, rej) => {
// chrome.permissions.contains(hostPermissions, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
// });
// }
export async function requestClipboardPermissions(): Promise<boolean> {
return new Promise((res, rej) => {
res(false);
// chrome.permissions.request({ permissions: ["clipboardRead"] }, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
});
}
// export async function requestHostPermissions(): Promise<boolean> {
// return new Promise((res, rej) => {
// chrome.permissions.request(hostPermissions, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
// });
// }
// type HeaderListenerFunc = (
// details: chrome.webRequest.WebResponseHeadersDetails,
// ) => void;
// let currentHeaderListener: HeaderListenerFunc | undefined = undefined;
// type TabListenerFunc = (tabId: number, info: chrome.tabs.TabChangeInfo) => void;
// let currentTabListener: TabListenerFunc | undefined = undefined;
// export async function removeHostPermissions(): Promise<boolean> {
// //if there is a handler already, remove it
// if (
// currentHeaderListener &&
// chrome?.webRequest?.onHeadersReceived?.hasListener(currentHeaderListener)
// ) {
// chrome.webRequest.onHeadersReceived.removeListener(currentHeaderListener);
// }
// if (
// currentTabListener &&
// chrome?.tabs?.onUpdated?.hasListener(currentTabListener)
// ) {
// chrome.tabs.onUpdated.removeListener(currentTabListener);
// }
// currentHeaderListener = undefined;
// currentTabListener = undefined;
// //notify the browser about this change, this operation is expensive
// if ("webRequest" in chrome) {
// chrome.webRequest.handlerBehaviorChanged(() => {
// if (chrome.runtime.lastError) {
// logger.error(JSON.stringify(chrome.runtime.lastError));
// }
// });
// }
// if (extensionIsManifestV3()) {
// // Trying to remove host permissions with manifest >= v3 throws an error
// return true;
// }
// return new Promise((res, rej) => {
// chrome.permissions.remove(hostPermissions, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
// });
// }
export function removeClipboardPermissions(): Promise<boolean> {
return new Promise((res, rej) => {
res(true);
// chrome.permissions.remove({ permissions: ["clipboardRead"] }, (resp) => {
// const le = chrome.runtime.lastError?.message;
// if (le) {
// rej(le);
// }
// res(resp);
// });
});
}
function addPermissionsListener(
callback: (p: Permissions, lastError?: string) => void,
): void {
chrome.permissions.onAdded.addListener((perm: Permissions) => {
const lastError = chrome.runtime.lastError?.message;
callback(perm, lastError);
});
}
function getPermissionsApi(): CrossBrowserPermissionsApi {
return {
addPermissionsListener,
// containsHostPermissions,
// requestHostPermissions,
// removeHostPermissions,
requestClipboardPermissions,
removeClipboardPermissions,
containsClipboardPermissions,
};
}
/**
*
* @param callback function to be called
*/
function notifyWhenAppIsReady(): Promise<void> {
return new Promise((resolve, reject) => {
if (extensionIsManifestV3()) {
resolve();
} else {
window.addEventListener("load", () => {
resolve();
});
}
});
}
function openWalletURIFromPopup(uri: TalerUri): void {
const talerUri = stringifyTalerUri(uri);
//FIXME: this should redirect to just one place
// the target pathname should handle what happens if the endpoint is not there
// like "trying to open from popup but this uri is not handled"
encodeURIComponent;
let url: string | undefined = undefined;
switch (uri.type) {
case TalerUriAction.WithdrawExchange:
case TalerUriAction.Withdraw:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/withdraw?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.Restore:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/recovery?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.Pay:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/pay?talerUri=${encodeURIComponent(talerUri)}`,
);
break;
case TalerUriAction.Tip:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/tip?talerUri=${encodeURIComponent(talerUri)}`,
);
break;
case TalerUriAction.Refund:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/refund?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.PayPull:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/invoice/pay?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.PayPush:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/transfer/pickup?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.PayTemplate:
url = chrome.runtime.getURL(
`static/wallet.html#/cta/pay/template?talerUri=${encodeURIComponent(
talerUri,
)}`,
);
break;
case TalerUriAction.DevExperiment:
logger.warn(`taler://dev-experiment URIs are not allowed in headers`);
return;
case TalerUriAction.Exchange:
logger.warn(`taler://exchange not yet supported`);
return;
case TalerUriAction.Auditor:
logger.warn(`taler://auditor not yet supported`);
return;
default: {
const error: never = uri;
logger.warn(
`Response with HTTP 402 the Taler header "${error}", but header value is not a taler:// URI.`,
);
return;
}
}
chrome.tabs.update({ active: true, url }, () => {
window.close();
});
}
function openWalletPage(page: string): void {
const url = chrome.runtime.getURL(`/static/wallet.html#${page}`);
chrome.tabs.create({ active: true, url });
}
function openWalletPageFromPopup(page: string): void {
const url = chrome.runtime.getURL(`/static/wallet.html#${page}`);
chrome.tabs.create({ active: true, url }, () => {
window.close();
});
}
let nextMessageIndex = 0;
/**
* To be used by the foreground
* @param message
* @returns
*/
async function sendMessageToBackground<
Op extends WalletOperations | BackgroundOperations,
>(message: MessageFromFrontend<Op>): Promise<MessageResponse> {
const messageWithId = { ...message, id: `id_${nextMessageIndex++ % 1000}` };
return new Promise<any>((resolve, reject) => {
logger.trace("send operation to the wallet background", message);
let timedout = false;
const timerId = setTimeout(() => {
timedout = true;
throw TalerError.fromDetail(TalerErrorCode.GENERIC_TIMEOUT, {});
}, 5 * 1000); //five seconds
chrome.runtime.sendMessage(messageWithId, (backgroundResponse) => {
if (timedout) {
return false; //already rejected
}
clearTimeout(timerId);
if (chrome.runtime.lastError) {
reject(chrome.runtime.lastError.message);
} else {
resolve(backgroundResponse);
}
// return true to keep the channel open
return true;
});
});
}
/**
* To be used by the foreground
*/
let notificationPort: chrome.runtime.Port | undefined;
function listenToWalletBackground(listener: (m: any) => void): () => void {
if (notificationPort === undefined) {
notificationPort = chrome.runtime.connect({ name: "notifications" });
}
notificationPort.onMessage.addListener(listener);
function removeListener(): void {
if (notificationPort !== undefined) {
notificationPort.onMessage.removeListener(listener);
}
}
return removeListener;
}
const allPorts: chrome.runtime.Port[] = [];
function sendMessageToAllChannels(message: MessageFromBackend): void {
for (const notif of allPorts) {
// const message: MessageFromBackend = { type: msg.type };
try {
notif.postMessage(message);
} catch (e) {
logger.error("error posting a message", e);
}
}
}
function registerAllIncomingConnections(): void {
chrome.runtime.onConnect.addListener((port) => {
try {
allPorts.push(port);
port.onDisconnect.addListener((discoPort) => {
try {
const idx = allPorts.indexOf(discoPort);
if (idx >= 0) {
allPorts.splice(idx, 1);
}
} catch (e) {
logger.error("error trying to remove connection", e);
}
});
} catch (e) {
logger.error("error trying to save incoming connection", e);
}
});
}
function listenToAllChannels(
notifyNewMessage: <Op extends WalletOperations | BackgroundOperations>(
message: MessageFromFrontend<Op> & { id: string },
) => Promise<MessageResponse>,
): void {
chrome.runtime.onMessage.addListener((message, sender, reply) => {
notifyNewMessage(message)
.then((apiResponse) => {
try {
reply(apiResponse);
} catch (e) {
logger.error(
"sending response to frontend failed",
message,
apiResponse,
e,
);
}
})
.catch((e) => {
logger.error("notify to background failed", e);
});
// keep the connection open
return true;
});
}
function registerReloadOnNewVersion(): void {
// Explicitly unload the extension page as soon as an update is available,
// so the update gets installed as soon as possible.
chrome.runtime.onUpdateAvailable.addListener((details) => {
logger.info("update available:", details);
chrome.runtime.reload();
});
}
function redirectTabToWalletPage(tabId: number, page: string): void {
const url = chrome.runtime.getURL(`/static/wallet.html#${page}`);
logger.trace("redirecting tabId: ", tabId, " to: ", url);
chrome.tabs.update(tabId, { url });
}
interface WalletVersion {
version_name?: string | undefined;
version: string;
}
function getWalletWebExVersion(): WalletVersion {
const manifestData = chrome.runtime.getManifest();
return manifestData;
}
const alertIcons = {
"16": "/static/img/taler-alert-16.png",
"19": "/static/img/taler-alert-19.png",
"32": "/static/img/taler-alert-32.png",
"38": "/static/img/taler-alert-38.png",
"48": "/static/img/taler-alert-48.png",
"64": "/static/img/taler-alert-64.png",
"128": "/static/img/taler-alert-128.png",
"256": "/static/img/taler-alert-256.png",
"512": "/static/img/taler-alert-512.png",
};
const normalIcons = {
"16": "/static/img/taler-logo-16.png",
"19": "/static/img/taler-logo-19.png",
"32": "/static/img/taler-logo-32.png",
"38": "/static/img/taler-logo-38.png",
"48": "/static/img/taler-logo-48.png",
"64": "/static/img/taler-logo-64.png",
"128": "/static/img/taler-logo-128.png",
"256": "/static/img/taler-logo-256.png",
"512": "/static/img/taler-logo-512.png",
};
function setNormalIcon(): void {
if (extensionIsManifestV3()) {
chrome.action.setIcon({ path: normalIcons });
} else {
chrome.browserAction.setIcon({ path: normalIcons });
}
}
function setAlertedIcon(): void {
if (extensionIsManifestV3()) {
chrome.action.setIcon({ path: alertIcons });
} else {
chrome.browserAction.setIcon({ path: alertIcons });
}
}
interface OffscreenCanvasRenderingContext2D
extends CanvasState,
CanvasTransform,
CanvasCompositing,
CanvasImageSmoothing,
CanvasFillStrokeStyles,
CanvasShadowStyles,
CanvasFilters,
CanvasRect,
CanvasDrawPath,
CanvasUserInterface,
CanvasText,
CanvasDrawImage,
CanvasImageData,
CanvasPathDrawingStyles,
CanvasTextDrawingStyles,
CanvasPath {
readonly canvas: OffscreenCanvas;
}
declare const OffscreenCanvasRenderingContext2D: {
prototype: OffscreenCanvasRenderingContext2D;
new (): OffscreenCanvasRenderingContext2D;
};
interface OffscreenCanvas extends EventTarget {
width: number;
height: number;
getContext(
contextId: "2d",
contextAttributes?: CanvasRenderingContext2DSettings,
): OffscreenCanvasRenderingContext2D | null;
}
declare const OffscreenCanvas: {
prototype: OffscreenCanvas;
new (width: number, height: number): OffscreenCanvas;
};
function createCanvas(size: number): OffscreenCanvas {
if (extensionIsManifestV3()) {
return new OffscreenCanvas(size, size);
} else {
const c = document.createElement("canvas");
c.height = size;
c.width = size;
return c;
}
}
async function createImage(size: number, file: string): Promise<ImageData> {
const r = await fetch(file);
const b = await r.blob();
const image = await createImageBitmap(b);
const canvas = createCanvas(size);
const canvasContext = canvas.getContext("2d")!;
canvasContext.clearRect(0, 0, canvas.width, canvas.height);
canvasContext.drawImage(image, 0, 0, canvas.width, canvas.height);
const imageData = canvasContext.getImageData(
0,
0,
canvas.width,
canvas.height,
);
return imageData;
}
async function registerIconChangeOnTalerContent(): Promise<void> {
const imgs = await Promise.all(
Object.entries(alertIcons).map(([key, value]) =>
createImage(parseInt(key, 10), value),
),
);
const imageData = imgs.reduce(
(prev, cur) => ({ ...prev, [cur.width]: cur }),
{} as { [size: string]: ImageData },
);
if (chrome.declarativeContent) {
// using declarative content does not need host permission
// and is faster
const secureTalerUrlLookup = {
conditions: [
new chrome.declarativeContent.PageStateMatcher({
css: ["a[href^='taler://'"],
}),
],
actions: [new chrome.declarativeContent.SetIcon({ imageData })],
};
const inSecureTalerUrlLookup = {
conditions: [
new chrome.declarativeContent.PageStateMatcher({
css: ["a[href^='taler+http://'"],
}),
],
actions: [new chrome.declarativeContent.SetIcon({ imageData })],
};
chrome.declarativeContent.onPageChanged.removeRules(undefined, function () {
chrome.declarativeContent.onPageChanged.addRules([
secureTalerUrlLookup,
inSecureTalerUrlLookup,
]);
});
return;
}
//this browser doesn't have declarativeContent
//we need host_permission and we will check the content for changing the icon
chrome.tabs.onUpdated.addListener(
async (tabId, info: chrome.tabs.TabChangeInfo) => {
if (tabId < 0) return;
if (info.status !== "complete") return;
const uri = await findTalerUriInTab(tabId);
if (uri) {
setAlertedIcon();
} else {
setNormalIcon();
}
},
);
chrome.tabs.onActivated.addListener(
async ({ tabId }: chrome.tabs.TabActiveInfo) => {
if (tabId < 0) return;
const uri = await findTalerUriInTab(tabId);
if (uri) {
setAlertedIcon();
} else {
setNormalIcon();
}
},
);
}
function registerOnInstalled(callback: () => void): void {
// This needs to be outside of main, as Firefox won't fire the event if
// the listener isn't created synchronously on loading the backend.
chrome.runtime.onInstalled.addListener(async (details) => {
logger.info(`onInstalled with reason: "${details.reason}"`);
if (details.reason === chrome.runtime.OnInstalledReason.INSTALL) {
callback();
}
await registerIconChangeOnTalerContent();
});
}
function extensionIsManifestV3(): boolean {
return chrome.runtime.getManifest().manifest_version === 3;
}
function useServiceWorkerAsBackgroundProcess(): boolean {
return extensionIsManifestV3();
}
function searchForTalerLinks(): string | undefined {
let found;
found = document.querySelector("a[href^='taler://'");
if (found) return found.toString();
found = document.querySelector("a[href^='taler+http://'");
if (found) return found.toString();
return undefined;
}
async function getCurrentTab(): Promise<chrome.tabs.Tab> {
const queryOptions = { active: true, currentWindow: true };
return new Promise<chrome.tabs.Tab>((resolve, reject) => {
chrome.tabs.query(queryOptions, (tabs) => {
if (chrome.runtime.lastError) {
reject(chrome.runtime.lastError);
return;
}
resolve(tabs[0]);
});
});
}
async function findTalerUriInTab(tabId: number): Promise<string | undefined> {
if (extensionIsManifestV3()) {
// manifest v3
try {
const res = await chrome.scripting.executeScript({
target: { tabId, allFrames: true },
func: searchForTalerLinks,
args: [],
});
return res[0].result;
} catch (e) {
return;
}
} else {
return new Promise((resolve, reject) => {
//manifest v2
chrome.tabs.executeScript(
tabId,
{
code: `
(() => {
let x = document.querySelector("a[href^='taler://'") || document.querySelector("a[href^='taler+http://'");
return x ? x.href.toString() : null;
})();
`,
allFrames: false,
},
(result) => {
if (chrome.runtime.lastError) {
logger.error(JSON.stringify(chrome.runtime.lastError));
resolve(undefined);
return;
}
resolve(result[0]);
},
);
});
}
}
async function timeout(ms: number): Promise<void> {
return new Promise((resolve) => setTimeout(resolve, ms));
}
async function findTalerUriInClipboard(): Promise<string | undefined> {
//FIXME: add clipboard feature
// try {
// //It looks like clipboard promise does not return, so we need a timeout
// const textInClipboard = await Promise.any([
// timeout(100),
// window.navigator.clipboard.readText(),
// ]);
// if (!textInClipboard) return;
// return textInClipboard.startsWith("taler://") ||
// textInClipboard.startsWith("taler+http://")
// ? textInClipboard
// : undefined;
// } catch (e) {
// logger.error("could not read clipboard", e);
// return undefined;
// }
return undefined;
}
async function findTalerUriInActiveTab(): Promise<string | undefined> {
const tab = await getCurrentTab();
if (!tab || tab.id === undefined) return;
return findTalerUriInTab(tab.id);
}
function listenNetworkConnectionState(
notify: (state: "on" | "off") => void,
): () => void {
function notifyOffline() {
notify("off");
}
function notifyOnline() {
notify("on");
}
window.addEventListener("offline", notifyOffline);
window.addEventListener("online", notifyOnline);
return () => {
window.removeEventListener("offline", notifyOffline);
window.removeEventListener("online", notifyOnline);
};
}
|