fix(whatsapp-plugin): connect with current WA Web version and load as bundled plugin

WhatsApp rejects handshakes advertising Baileys' baked-in stale protocol
version with a 405 close, so the plugin cycled starting->disconnected and
never issued a QR. connect() now fetches the current WA Web version per
socket build. /status also exposes lastError so this failure mode is
diagnosable from the documented troubleshooting surface.

The published bundled.js also failed to load entirely ("Dynamic require
of 'crypto' is not supported"): plugin bundles are ESM but Baileys is
CJS. bundlePluginEntry now injects the same createRequire banner as
dist/bin.js.

Verified end-to-end against an isolated fn serve: bundled.js loads,
status reaches awaiting-qr, /qr serves a scannable QR data URL,
/pair-code validates input, /logout clears auth state.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.changeset/whatsapp-plugin-connects-again.md

@@ -0,0 +1,7 @@
+---
+"@runfusion/fusion": patch
+---
+
+summary: Fix WhatsApp Chat plugin failing to connect (405 rejection) and its bundled build failing to load.
+category: fix
+dev: connect() now passes fetchLatestBaileysVersion() to makeWASocket so WhatsApp accepts the handshake; /status exposes lastError; plugin bundled.js builds get the createRequire ESM banner so CJS deps (Baileys) can require node builtins.

packages/cli/tsup.config.ts

@@ -203,6 +203,13 @@ async function bundlePluginEntry({ pluginId, srcDir, destDir, withMcpAsset = fal
     target: "node22",
     outfile: join(destDir, "bundled.js"),
     external: ["@fusion/engine", ...external],
+    /*
+     * FNXC:BundledPlugins 2026-07-17-09:20:
+     * CJS dependencies bundled into ESM output (e.g. Baileys in the WhatsApp plugin) compile to esbuild's __require helper, which throws "Dynamic require of \"crypto\" is not supported" at load time in an ESM module. Inject the same createRequire shim dist/bin.js uses so every bundled.js can require node builtins.
+     */
+    banner: {
+      js: 'import { createRequire as __createRequire } from "node:module"; const require = __createRequire(import.meta.url);',
+    },
     alias: {
       "@fusion/plugin-sdk": join(__dirname, "..", "plugin-sdk", "src", "index.ts"),
       /*

plugins/fusion-plugin-whatsapp-chat/src/__tests__/connection.test.ts

@@ -24,6 +24,7 @@ const mockState = vi.hoisted(() => {
 vi.mock("@whiskeysockets/baileys", () => ({
   default: mockState.makeWASocket,
   makeWASocket: mockState.makeWASocket,
+  fetchLatestBaileysVersion: async () => ({ version: [2, 3000, 0], isLatest: true }),
   DisconnectReason: { loggedOut: 401 },
   BufferJSON: { reviver: undefined, replacer: undefined },
   initAuthCreds: () => ({}),
@@ -140,11 +141,12 @@ describe("WhatsAppConnection", () => {
     const connection = new WhatsAppConnection(makeCtx(), "0.1.0", vi.fn().mockResolvedValue("reply"), createInMemoryPersistence());
     await connection.start();
     await mockState.handlers.get("connection.update")?.({ connection: "close", lastDisconnect: { error: new Error("boom") } });
-    vi.advanceTimersByTime(1000);
+    // connect() awaits fetchLatestBaileysVersion before building the socket, so flush microtasks after the timer fires.
+    await vi.advanceTimersByTimeAsync(1000);
     expect(mockState.makeWASocket).toHaveBeenCalledTimes(2);
 
     await mockState.handlers.get("connection.update")?.({ connection: "close", lastDisconnect: { error: { output: { statusCode: 401 } } } });
-    vi.advanceTimersByTime(1000);
+    await vi.advanceTimersByTimeAsync(1000);
     expect(mockState.makeWASocket).toHaveBeenCalledTimes(2);
     vi.useRealTimers();
   });

plugins/fusion-plugin-whatsapp-chat/src/connection.ts

@@ -1,4 +1,4 @@
-import { DisconnectReason, makeWASocket, type ConnectionState, type WAMessage, type WAMessageContent, type WASocket } from "@whiskeysockets/baileys";
+import { DisconnectReason, fetchLatestBaileysVersion, makeWASocket, type ConnectionState, type WAMessage, type WAMessageContent, type WASocket } from "@whiskeysockets/baileys";
 import type { PluginContext } from "@fusion/plugin-sdk";
 import pino from "pino";
 import qrcode from "qrcode";
@@ -156,7 +156,13 @@ export class WhatsAppConnection {
     if (!this.authState) this.authState = await createPersistenceAuthState(this.persistence);
 
     this.status = { state: "starting" };
+    /**
+     * FNXC:WhatsAppProtocolVersion 2026-07-17-09:15:
+     * WhatsApp rejects handshakes that advertise a stale WA Web protocol version with a 405 "Connection Failure" close, which left the plugin stuck cycling starting→disconnected and no QR was ever issued. Fetch the current version before each socket build; fetchLatestBaileysVersion falls back to the library's baked-in version on network failure, so this never blocks connecting.
+     */
+    const { version } = await fetchLatestBaileysVersion();
     const socket = makeWASocket({
+      version,
       auth: this.authState.state,
       printQRInTerminal: false,
       browser: ["Fusion", "Chrome", this.fusionVersion],

plugins/fusion-plugin-whatsapp-chat/src/index.ts

@@ -95,11 +95,16 @@ const routes: PluginRouteDefinition[] = [
       const { connection, error } = getConnectionOrResponse(ctx);
       if (!connection) return error as PluginRouteResponse;
       const status = connection.getStatus();
+      /**
+       * FNXC:WhatsAppStatusVisibility 2026-07-17-09:15:
+       * /status must expose lastError: a stale-protocol 405 rejection previously showed only a bare "disconnected" with no way to diagnose it from the API surface the README points troubleshooters at.
+       */
       return {
         status: 200,
         body: {
           status: status.state,
           jid: status.jid,
+          lastError: status.lastError,
           allowedSenders: Array.from(getAllowedSenders(ctx.settings)),
         },
       };