Add saleorApiUrl state param to AppBridge (#114)

* Add saleorApiUrl state param to AppBridge

* Apply payload verification check based on full api endpoint url

* Remove deprecation info

* Check if either domain or saleorApiUrl is provided

docs/app-bridge.md

@@ -17,6 +17,8 @@ Options object is following:
 ```
 type AppBridgeOptions = {
   targetDomain?: string;
+  saleorApiUrl?: string;
+  initialLocale?: LocaleCode;
 };
 ```
 
@@ -36,6 +38,11 @@ type AppBridgeState = {
   domain: string;
   path: string;
   theme: ThemeType;
+  locale: LocaleCode; // See src/locales.ts
+  /**
+   * Full URL including protocol and path where graphql is available
+   */
+  saleorApiUrl: string;
 };
 ```
 

src/app-bridge/app-bridge-provider.test.tsx

@@ -4,10 +4,12 @@ import { describe, expect, it, vi } from "vitest";
 
 import { AppBridge } from "./app-bridge";
 import { AppBridgeProvider, useAppBridge } from "./app-bridge-provider";
+import { AppIframeParams } from "./app-iframe-params";
 import { DashboardEventFactory } from "./events";
 
 const origin = "http://example.com";
 const domain = "saleor.domain.host";
+const apiUrl = "https://saleor.domain.host/graphql/";
 
 Object.defineProperty(window.document, "referrer", {
   value: origin,
@@ -16,7 +18,7 @@ Object.defineProperty(window.document, "referrer", {
 
 Object.defineProperty(window, "location", {
   value: {
-    href: `${origin}?domain=${domain}&id=appid`,
+    href: `${origin}?${AppIframeParams.DOMAIN}=${domain}&${AppIframeParams.APP_ID}=appid&${AppIframeParams.SALEOR_API_URL}=${apiUrl}`,
   },
   writable: true,
 });
@@ -37,7 +39,8 @@ describe("AppBridgeProvider", () => {
       <AppBridgeProvider
         appBridgeInstance={
           new AppBridge({
-            targetDomain: "https://test-domain",
+            targetDomain: domain,
+            saleorApiUrl: apiUrl,
           })
         }
       >
@@ -86,19 +89,20 @@ describe("useAppBridge hook", () => {
 
   it("Returned instance provided in Provider", () => {
     const appBridge = new AppBridge({
-      targetDomain: "test-domain",
+      targetDomain: domain,
     });
 
     const { result } = renderHook(() => useAppBridge(), {
       wrapper: (props: {}) => <AppBridgeProvider {...props} appBridgeInstance={appBridge} />,
     });
 
-    expect(result.current.appBridge?.getState().domain).toBe("test-domain");
+    expect(result.current.appBridge?.getState().domain).toBe(domain);
   });
 
   it("Stores active state in React State", () => {
     const appBridge = new AppBridge({
-      targetDomain: origin,
+      targetDomain: domain,
+      saleorApiUrl: apiUrl,
     });
 
     const renderCallback = vi.fn();
@@ -128,12 +132,13 @@ describe("useAppBridge hook", () => {
     return waitFor(() => {
       expect(renderCallback).toHaveBeenCalledTimes(2);
       expect(renderCallback).toHaveBeenCalledWith({
-        domain: "http://example.com",
+        domain,
         id: "appid",
         path: "",
         ready: false,
         theme: "light",
         locale: "en",
+        saleorApiUrl: apiUrl,
       });
     });
   });

src/app-bridge/app-bridge-state.test.ts

@@ -13,6 +13,7 @@ describe("app-bridge-state.ts", () => {
       path: "/",
       theme: "light",
       locale: "en",
+      saleorApiUrl: "",
     });
   });
 
@@ -20,7 +21,8 @@ describe("app-bridge-state.ts", () => {
     const instance = new AppBridgeStateContainer();
 
     const newState: Partial<AppBridgeState> = {
-      domain: "https://my-saleor-instance.cloud",
+      domain: "my-saleor-instance.cloud",
+      saleorApiUrl: "https://my-saleor-instance.cloud/graphql/",
       id: "foo-bar",
       path: "/",
       theme: "light",

src/app-bridge/app-bridge-state.ts

@@ -9,6 +9,7 @@ export type AppBridgeState = {
   path: string;
   theme: ThemeType;
   locale: LocaleCode;
+  saleorApiUrl: string;
 };
 
 type Options = {
@@ -19,6 +20,7 @@ export class AppBridgeStateContainer {
   private state: AppBridgeState = {
     id: "",
     domain: "",
+    saleorApiUrl: "",
     ready: false,
     path: "/",
     theme: "light",

src/app-bridge/app-bridge.ts

@@ -3,6 +3,7 @@ import debugPkg from "debug";
 import { LocaleCode } from "../locales";
 import { Actions } from "./actions";
 import { AppBridgeState, AppBridgeStateContainer } from "./app-bridge-state";
+import { AppIframeParams } from "./app-iframe-params";
 import { SSR } from "./constants";
 import { Events, EventType, PayloadOfEvent, ThemeType } from "./events";
 
@@ -68,6 +69,7 @@ const createEmptySubscribeMap = (): SubscribeMap => ({
 
 export type AppBridgeOptions = {
   targetDomain?: string;
+  saleorApiUrl?: string;
   initialLocale?: LocaleCode;
 };
 
@@ -75,16 +77,22 @@ export type AppBridgeOptions = {
  * TODO: Consider validating locale if wrong code provided
  */
 const getLocaleFromUrl = () =>
-  (new URL(window.location.href).searchParams.get("locale") as LocaleCode) || undefined;
+  (new URL(window.location.href).searchParams.get(AppIframeParams.LOCALE) as LocaleCode) ||
+  undefined;
 
 /**
  * TODO: Probably remove empty string fallback
  */
-const getDomainFromUrl = () => new URL(window.location.href).searchParams.get("domain") || "";
+const getDomainFromUrl = () =>
+  new URL(window.location.href).searchParams.get(AppIframeParams.DOMAIN) || "";
+
+const getSaleorApiUrlFromUrl = () =>
+  new URL(window.location.href).searchParams.get(AppIframeParams.SALEOR_API_URL) || "";
 
 const getDefaultOptions = (): AppBridgeOptions => ({
   targetDomain: getDomainFromUrl(),
-  initialLocale: getLocaleFromUrl(),
+  saleorApiUrl: getSaleorApiUrlFromUrl(),
+  initialLocale: getLocaleFromUrl() ?? "en",
 });
 
 export class AppBridge {
@@ -121,9 +129,17 @@ export class AppBridge {
       console.warn("document.referrer is empty");
     }
 
+    if (!this.combinedOptions.saleorApiUrl) {
+      debug("?saleorApiUrl was not found in iframe url");
+    }
+
     if (!this.combinedOptions.targetDomain) {
+      debug("?domain was not found in iframe url");
+    }
+
+    if (!(this.combinedOptions.saleorApiUrl && this.combinedOptions.targetDomain)) {
       console.error(
-        "No domain set, ensure ?domain param in iframe exist or provide in AppBridge constructor"
+        "domain and saleorApiUrl params were not found in iframe url. Ensure at least one of them is present"
       );
     }
 
@@ -243,11 +259,19 @@ export class AppBridge {
     debug("setInitialState() called");
 
     const url = new URL(window.location.href);
-    const id = url.searchParams.get("id") || "";
+    const id = url.searchParams.get(AppIframeParams.APP_ID) || "";
     const path = window.location.pathname || "";
-    const theme: ThemeType = url.searchParams.get("theme") === "light" ? "light" : "dark";
+    const theme: ThemeType =
+      url.searchParams.get(AppIframeParams.THEME) === "light" ? "light" : "dark";
 
-    const state = { domain: this.combinedOptions.targetDomain, id, path, theme };
+    const state: Partial<AppBridgeState> = {
+      domain: this.combinedOptions.targetDomain,
+      id,
+      path,
+      theme,
+      saleorApiUrl: this.combinedOptions.saleorApiUrl,
+      locale: this.combinedOptions.initialLocale,
+    };
 
     debug("setInitialState() will setState with %j", state);
 

src/app-bridge/app-iframe-params.ts

@@ -0,0 +1,10 @@
+/**
+ * Contains keys of SearchParams added to iframe src
+ */
+export const AppIframeParams = {
+  APP_ID: "id",
+  THEME: "theme",
+  DOMAIN: "domain",
+  SALEOR_API_URL: "saleorApiUrl",
+  LOCALE: "locale",
+};

src/app-bridge/index.ts

@@ -4,6 +4,7 @@ export { AppBridge };
 
 export * from "./actions";
 export * from "./app-bridge-provider";
+export * from "./app-iframe-params";
 export * from "./events";
 export * from "./types";
 export * from "./use-dashboard-token";

src/const.ts

@@ -2,5 +2,6 @@ export const SALEOR_DOMAIN_HEADER = "saleor-domain";
 export const SALEOR_EVENT_HEADER = "saleor-event";
 export const SALEOR_SIGNATURE_HEADER = "saleor-signature";
 export const SALEOR_AUTHORIZATION_BEARER_HEADER = "authorization-bearer";
+export const SALEOR_API_URL_HEADER = "saleor-api-url";
 
 export * from "./locales";

src/handlers/next/process-async-saleor-webhook.test.ts

@@ -13,6 +13,11 @@ vi.mock("./../../verify-signature", () => ({
       throw new Error("Wrong signature");
     }
   }),
+  verifySignatureFromApiUrl: vi.fn((domain, signature) => {
+    if (signature !== "mocked_signature") {
+      throw new Error("Wrong signature");
+    }
+  }),
 }));
 
 vi.mock("raw-body", () => ({
@@ -43,6 +48,7 @@ describe("processAsyncSaleorWebhook", () => {
         host: "some-saleor-host.cloud",
         "x-forwarded-proto": "https",
         "saleor-domain": "example.com",
+        "saleor-api-url": "https://example.com/graphql/",
         "saleor-event": "product_updated",
         "saleor-signature": "mocked_signature",
         "content-length": "0", // is ignored by mocked raw-body

src/handlers/next/process-async-saleor-webhook.ts

@@ -5,7 +5,7 @@ import { APL } from "../../APL";
 import { AuthData } from "../../APL/apl";
 import { createDebug } from "../../debug";
 import { getBaseUrl, getSaleorHeaders } from "../../headers";
-import { verifySignature } from "../../verify-signature";
+import { verifySignature, verifySignatureFromApiUrl } from "../../verify-signature";
 
 const debug = createDebug("processAsyncWebhook");
 
@@ -69,7 +69,7 @@ export const processAsyncSaleorWebhook: ProcessAsyncSaleorWebhook = async <T>({
     debug("Wrong HTTP method");
     throw new WebhookError("Wrong request method, only POST allowed", "WRONG_METHOD");
   }
-  const { event, domain, signature } = getSaleorHeaders(req.headers);
+  const { event, domain, signature, saleorApiUrl } = getSaleorHeaders(req.headers);
   const baseUrl = getBaseUrl(req.headers);
 
   if (!baseUrl) {
@@ -134,7 +134,14 @@ export const processAsyncSaleorWebhook: ProcessAsyncSaleorWebhook = async <T>({
   // Payload signature check
   // TODO: Since it require additional request, can we cache it's response?
   try {
+    /**
+     * saleorApiUrl is a new header, is it if available. Verification by domain will be removed in future versions
+     */
+    if (saleorApiUrl) {
+      await verifySignatureFromApiUrl(saleorApiUrl, signature, rawBody);
+    } else {
       await verifySignature(domain, signature, rawBody);
+    }
   } catch {
     debug("Request signature check failed");
     throw new WebhookError("Request signature check failed", "SIGNATURE_VERIFICATION_FAILED");

src/handlers/next/saleor-async-webhook.ts

@@ -127,9 +127,6 @@ export class SaleorAsyncWebhook<TPayload = unknown> {
   /**
    * Wraps provided function, to ensure incoming request comes from registered Saleor instance.
    * Also provides additional `context` object containing typed payload and request properties.
-   *
-   * @param handlerFn NextApiHandler function which takes additional `context` argument
-   * @returns NextApiHandler
    */
   createHandler(handlerFn: NextWebhookApiHandler<TPayload>): NextApiHandler {
     return async (req, res) => {

src/headers.ts

@@ -1,4 +1,5 @@
 import {
+  SALEOR_API_URL_HEADER,
   SALEOR_AUTHORIZATION_BEARER_HEADER,
   SALEOR_DOMAIN_HEADER,
   SALEOR_EVENT_HEADER,
@@ -8,13 +9,12 @@ import {
 const toStringOrUndefined = (value: string | string[] | undefined) =>
   value ? value.toString() : undefined;
 
-export const getSaleorHeaders = (headers: {
-  [name: string]: string | string[] | undefined;
-}): Record<string, string | undefined> => ({
+export const getSaleorHeaders = (headers: { [name: string]: string | string[] | undefined }) => ({
   domain: toStringOrUndefined(headers[SALEOR_DOMAIN_HEADER]),
   authorizationBearer: toStringOrUndefined(headers[SALEOR_AUTHORIZATION_BEARER_HEADER]),
   signature: toStringOrUndefined(headers[SALEOR_SIGNATURE_HEADER]),
   event: toStringOrUndefined(headers[SALEOR_EVENT_HEADER]),
+  saleorApiUrl: toStringOrUndefined(headers[SALEOR_API_URL_HEADER]),
 });
 
 export const getBaseUrl = (headers: { [name: string]: string | string[] | undefined }): string => {

src/urls.ts

@@ -4,9 +4,18 @@
 const resolveUrlProtocol = (saleorDomain: string): string =>
   saleorDomain === "localhost:8000" ? "http" : "https";
 
+/**
+ * @deprecated use getJwksUrlFromSaleorApiUrl
+ */
 export const getJwksUrl = (saleorDomain: string): string =>
   `${resolveUrlProtocol(saleorDomain)}://${saleorDomain}/.well-known/jwks.json`;
 
+export const getJwksUrlFromSaleorApiUrl = (saleorApiUrl: string): string =>
+  `${new URL(saleorApiUrl).origin}/.well-known/jwks.json`;
+
+/**
+ * @deprecated Use saleor-api-url header
+ */
 export const getGraphQLUrl = (saleorDomain: string): string =>
   `${resolveUrlProtocol(saleorDomain)}://${saleorDomain}/graphql/`;
 

src/verify-signature.ts

@@ -1,13 +1,13 @@
 import * as jose from "jose";
 
 import { createDebug } from "./debug";
-import { getJwksUrl } from "./urls";
+import { getJwksUrl, getJwksUrlFromSaleorApiUrl } from "./urls";
 
 const debug = createDebug("verify-signature");
 
 /**
- * Verify payload signature with public key of given `domain`
- * https://docs.saleor.io/docs/3.x/developer/extending/apps/asynchronous-webhooks#payload-signature
+ * @deprecated
+ * use verifySignatureFromApiUrl
  */
 export const verifySignature = async (domain: string, signature: string, rawBody: string) => {
   const [header, , jwsSignature] = signature.split(".");
@@ -31,3 +31,34 @@ export const verifySignature = async (domain: string, signature: string, rawBody
     throw new Error("JWKS verification failed");
   }
 };
+
+/**
+ * Verify payload signature with public key of given `domain`
+ * https://docs.saleor.io/docs/3.x/developer/extending/apps/asynchronous-webhooks#payload-signature
+ */
+export const verifySignatureFromApiUrl = async (
+  apiUrl: string,
+  signature: string,
+  rawBody: string
+) => {
+  const [header, , jwsSignature] = signature.split(".");
+  const jws: jose.FlattenedJWSInput = {
+    protected: header,
+    payload: rawBody,
+    signature: jwsSignature,
+  };
+
+  const remoteJwks = jose.createRemoteJWKSet(
+    new URL(getJwksUrlFromSaleorApiUrl(apiUrl))
+  ) as jose.FlattenedVerifyGetKey;
+
+  debug("Created remote JWKS");
+
+  try {
+    await jose.flattenedVerify(jws, remoteJwks);
+    debug("JWKS verified");
+  } catch {
+    debug("JWKS verification failed");
+    throw new Error("JWKS verification failed");
+  }
+};