feat(js): export composable launchPersistentContext helpers

Author: regseb

js/src/index.ts

@@ -16,7 +16,16 @@
  */
 
 // Launch functions (Playwright API)
-export { launch, launchContext, launchPersistentContext, buildLaunchOptions, buildContextOptions, humanizeBrowser } from "./playwright.js";
+export {
+    launch,
+    launchContext,
+    launchPersistentContext,
+    buildLaunchOptions,
+    buildLaunchPersistentContextOptions,
+    buildContextOptions,
+    humanizeBrowser,
+    humanizeContext
+} from "./playwright.js";
 
 // Binary management
 export { ensureBinary, clearCache, binaryInfo, checkForUpdate } from "./download.js";

js/src/playwright.ts

@@ -3,7 +3,13 @@
  * Mirrors Python cloakbrowser/browser.py.
  */
 
-import type { Browser, BrowserContext, BrowserContextOptions, LaunchOptions as PlaywrightLaunchOptions } from "playwright-core";
+import type {
+  Browser,
+  BrowserContext,
+  BrowserContextOptions,
+  BrowserType,
+  LaunchOptions as PlaywrightLaunchOptions
+} from "playwright-core";
 import type { LaunchOptions, LaunchContextOptions, LaunchPersistentContextOptions } from "./types.js";
 import { DEFAULT_VIEWPORT, IGNORE_DEFAULT_ARGS } from "./config.js";
 import { buildArgs } from "./args.js";
@@ -71,6 +77,7 @@ function effectiveHeadless(options: LaunchOptions): boolean {
 export function buildContextOptions(
   options: LaunchContextOptions = {}
 ): BrowserContextOptions {
+  options = resolveTimezone(options);
   // Headed: viewport=null (no emulation) so the page tracks the real window and
   // outerWidth >= innerWidth stays coherent — CDP viewport emulation forces
   // inner > outer = a physically impossible window = bot tell. Headless has no
@@ -123,6 +130,27 @@ export async function buildLaunchOptions(
   } as PlaywrightLaunchOptions;
 }
 
+/**
+ * Build Playwright launchPersistentContextOptions options for CloakBrowser
+ * without starting Chromium.
+ *
+ * Useful when integrating CloakBrowser with a custom Playwright build or another
+ * wrapper that needs to call `chromium.launchPersistentContext()` itself.
+ */
+export async function buildLaunchPersistentContextOptions(
+    options: LaunchPersistentContextOptions
+): Promise<Parameters<BrowserType["launchPersistentContext"]>[1]> {
+  const launchOptions = await buildLaunchOptions(options);
+  const contextOptions = buildContextOptions(options);
+
+  seedWidevineHint(options.userDataDir, launchOptions.executablePath as string);
+
+  return {
+    ...launchOptions,
+    ...contextOptions,
+  }
+}
+
 /**
  * Apply CloakBrowser's human-like behavioral layer to an existing Playwright browser.
  */
@@ -141,6 +169,24 @@ export async function humanizeBrowser(
   patchBrowser(browser, cfg);
 }
 
+/**
+ * Apply CloakBrowser's human-like behavioral layer to an existing Playwright context.
+ */
+export async function humanizeContext(
+    context: BrowserContext,
+    options: LaunchContextOptions = {}
+): Promise<void> {
+  if (!options.humanize) return;
+
+  const { patchContext } = await import('./human/index.js');
+  const { resolveConfig } = await import('./human/config.js');
+  const cfg = resolveConfig(
+    options.humanPreset ?? 'default',
+    options.humanConfig,
+  );
+  patchContext(context, cfg);
+}
+
 /**
  * Launch stealth Chromium browser via Playwright.
  *
@@ -203,20 +249,7 @@ function applyDefaultNoViewport(browser: Browser): void {
 export async function launchContext(
   options: LaunchContextOptions = {}
 ): Promise<BrowserContext> {
-  options = resolveTimezone(options);
-  // Resolve geoip BEFORE launch() to avoid double-resolution
-  const { exitIp, ...resolved } = await maybeResolveGeoip(options);
-  let launchArgs = await resolveWebrtcArgs(options);
-  // Inject geoip exit IP for WebRTC spoofing (free — no extra HTTP call)
-  if (exitIp && !(launchArgs ?? []).some(a => a.startsWith("--fingerprint-webrtc-ip"))) {
-    launchArgs = [...(launchArgs ?? []), `--fingerprint-webrtc-ip=${exitIp}`];
-  }
-  // --fingerprint-timezone is process-wide (reads CommandLine in renderer),
-  // so it applies to ALL contexts, not just the default one.
-  // locale and timezone are set via binary flags only — no CDP emulation.
-  // humanize:false on the inner launch — patchContext below applies humanize
-  // exactly once (else launch()'s humanizeBrowser would patch it a second time).
-  const browser = await launch({ ...options, ...resolved, args: launchArgs, geoip: false, humanize: false });
+  const browser = await launch(options);
 
   let context: BrowserContext;
   try {
@@ -233,17 +266,7 @@ export async function launchContext(
     await browser.close();
   };
 
-  // Human-like behavioral patching
-  if (options.humanize) {
-    const { patchContext } = await import('./human/index.js');
-    const { resolveConfig } = await import('./human/config.js');
-    const cfg = resolveConfig(
-      options.humanPreset ?? 'default',
-      options.humanConfig,
-    );
-    patchContext(context, cfg);
-  }
-
+  await humanizeContext(context, options);
   return context;
 }
 
@@ -271,45 +294,12 @@ export async function launchContext(
 export async function launchPersistentContext(
   options: LaunchPersistentContextOptions
 ): Promise<BrowserContext> {
-  options = resolveTimezone(options);
   const { chromium } = await import("playwright-core");
-
-  const binaryPath =
-    process.env.CLOAKBROWSER_BINARY_PATH ||
-    (await ensureBinary(options.licenseKey, options.browserVersion));
-  const { exitIp, ...resolved } = await maybeResolveGeoip(options);
-  const { proxyOption, proxyArgs } = resolveProxyConfig(options.proxy, options.browserVersion);
-  let resolvedArgs = await resolveWebrtcArgs(options);
-  if (exitIp && !(resolvedArgs ?? []).some(a => a.startsWith("--fingerprint-webrtc-ip"))) {
-    resolvedArgs = [...(resolvedArgs ?? []), `--fingerprint-webrtc-ip=${exitIp}`];
-  }
-  const args = buildArgs({ ...options, ...resolved, args: [...(resolvedArgs ?? []), ...proxyArgs] });
-
-  seedWidevineHint(options.userDataDir, binaryPath);
-
-  // locale and timezone are set via binary flags (--lang, --fingerprint-timezone)
-  // — NOT via Playwright context kwargs which use detectable CDP emulation.
-  const context = await chromium.launchPersistentContext(options.userDataDir, {
-    executablePath: binaryPath,
-    headless: options.headless ?? true,
-    args,
-    ignoreDefaultArgs: IGNORE_DEFAULT_ARGS,
-    ...(proxyOption ? { proxy: proxyOption } : {}),
-    ...buildContextOptions(options),
-    ...options.launchOptions,
-  });
-
-  // Human-like behavioral patching
-  if (options.humanize) {
-    const { patchContext } = await import('./human/index.js');
-    const { resolveConfig } = await import('./human/config.js');
-    const cfg = resolveConfig(
-      options.humanPreset ?? 'default',
-      options.humanConfig,
-    );
-    patchContext(context, cfg);
-  }
-
+  const context = await chromium.launchPersistentContext(
+    options.userDataDir,
+    await buildLaunchPersistentContextOptions(options),
+  );
+  await humanizeContext(context, options);
   return context;
 }
 

js/tests/launch.test.ts

@@ -176,6 +176,47 @@ describe("composable Playwright launch helpers", () => {
     }
   });
 
+  it("buildLaunchPersistentContextOptions returns Playwright options without launching a browser", async () => {
+    const freshConfig = await import("../src/config.js");
+    vi.spyOn(freshConfig, "getPlatformTag").mockReturnValue("darwin-arm64");
+    try {
+      const { buildLaunchPersistentContextOptions } = await import("../src/index.js");
+
+      const options = await buildLaunchPersistentContextOptions({
+        userDataDir: "/fake/data-dir",
+        headless: false,
+        proxy: "http://user:pass@proxy.example:8080",
+        args: ["--custom-flag"],
+        viewport: { width: 1900, height: 1080 },
+        colorScheme: "dark",
+        launchOptions: { slowMo: 1234 },
+        contextOptions: {
+          acceptDownloads: true,
+          locale: "fr-FR",
+        },
+      });
+
+      expect(options).toMatchObject({
+        executablePath: "/fake/chrome",
+        headless: false,
+        proxy: {
+          server: "http://proxy.example:8080",
+          username: "user",
+          password: "pass",
+        },
+        viewport: { width: 1900, height: 1080 },
+        colorScheme: "dark",
+        slowMo: 1234,
+        acceptDownloads: true,
+      });
+      expect(options.args).toContain("--custom-flag");
+      expect(options.ignoreDefaultArgs).toContain("--enable-automation");
+      expect(options.locale).toBeUndefined();
+    } finally {
+      vi.restoreAllMocks();
+    }
+  });
+
   it("humanizeBrowser patches an existing browser only when requested", async () => {
     const { humanizeBrowser } = await import("../src/index.js");
     const browser = {
@@ -191,6 +232,22 @@ describe("composable Playwright launch helpers", () => {
     await humanizeBrowser(browser as any, { humanize: true });
     expect(browser.newContext).not.toBe(originalNewContext);
   });
+
+  it("humanizeContext patches an existing context only when requested", async () => {
+    const { humanizeContext } = await import("../src/index.js");
+    const context = {
+      pages: () => [],
+      on: vi.fn(() => undefined),
+      newPage: vi.fn(async () => ({})),
+    };
+    const originalNewPage = context.newPage;
+
+    await humanizeContext(context as any, { humanize: false });
+    expect(context.newPage).toBe(originalNewPage);
+
+    await humanizeContext(context as any, { humanize: true });
+    expect(context.newPage).not.toBe(originalNewPage);
+  });
 });
 
 // Integration tests require the binary — run with: