Add --internal-cookie-store option for Playground CLI (#2323)

## Description

Adds a new `--internal-cookie-store` flag in the Playground CLI and a
corresponding `internalCookieStore` argument in `RunCLIArgs`. When
enabled, all the cookies are stored and served from an internal cookie
jar. By default, that option is disabled and the user agent is
responsible for handling cookies.

## Motivation

Some workflows need Playground to own cookie persistence, e.g. VS Code
webview does not store cookies so any Blueprint with autologin enabled
results in an infinite redirection loop.

## Testing steps

* Start Playground CLI without the flag and confirm that WordPress sends
a `set-cookie` header both on the homepage and when logging in.
* Restart it with `--internal-cookie-store` and verify no cookies are
sent to the browser. Confirm the admin login form still works.

cc @bgrgicak @ryanwelcher

Author: adamziel

packages/playground/cli/src/run-cli.ts

@@ -181,6 +181,14 @@ export async function parseOptionsAndRunCLI() {
 			// Hide this option because we want to replace with a more general log-level flag.
 			hidden: true,
 		})
+		.option('internal-cookie-store', {
+			describe:
+				'Enable internal cookie handling. When enabled, Playground will manage cookies internally using ' +
+				'an HttpCookieStore that persists cookies across requests. When disabled, cookies are handled ' +
+				'externally (e.g., by a browser in Node.js environments).',
+			type: 'boolean',
+			default: false,
+		})
 		// TODO: Should we make this a hidden flag?
 		.option('experimentalMultiWorker', {
 			describe:
@@ -283,6 +291,7 @@ export interface RunCLIArgs {
 	followSymlinks?: boolean;
 	experimentalMultiWorker?: number;
 	experimentalTrace?: boolean;
+	internalCookieStore?: boolean;
 }
 
 export interface RunCLIServer extends AsyncDisposable {
@@ -638,6 +647,7 @@ export async function runCLI(args: RunCLIArgs): Promise<RunCLIServer> {
 					processIdSpaceLength,
 					followSymlinks,
 					trace,
+					internalCookieStore: args.internalCookieStore,
 				});
 
 				if (
@@ -728,6 +738,7 @@ export async function runCLI(args: RunCLIArgs): Promise<RunCLIServer> {
 								processIdSpaceLength,
 								followSymlinks,
 								trace,
+								internalCookieStore: args.internalCookieStore,
 							});
 							await additionalPlayground.isReady();
 

packages/playground/cli/src/worker-thread.ts

@@ -32,6 +32,14 @@ export type PrimaryWorkerBootOptions = {
 	dataSqlPath?: string;
 	followSymlinks: boolean;
 	trace: boolean;
+	/**
+	 * When true, Playground will not send cookies to the client but will manage
+	 * them internally. This can be useful in environments that can't store cookies,
+	 * e.g. VS Code WebView.
+	 *
+	 * Default: false.
+	 */
+	internalCookieStore?: boolean;
 };
 
 function mountResources(php: PHP, mounts: Mount[]) {
@@ -110,6 +118,7 @@ export class PlaygroundCliWorker extends PHPWorker {
 		dataSqlPath,
 		followSymlinks,
 		trace,
+		internalCookieStore,
 	}: PrimaryWorkerBootOptions) {
 		if (this.booted) {
 			throw new Error('Playground already booted');
@@ -175,7 +184,7 @@ export class PlaygroundCliWorker extends PHPWorker {
 						mountResources(php, mountsBeforeWpInstall);
 					},
 				},
-				cookieStore: false,
+				cookieStore: internalCookieStore ? undefined : false,
 				dataSqlPath,
 			});
 			this.__internal_setRequestHandler(requestHandler);