Wp Playground

Sites API and active site client

Use this reference for browser JavaScript operations on the Playground website when selected by the interaction router.

• window.playgroundSites manages saved browser sites and the active site selection.

• window.playground is the PlaygroundClient for the active WordPress runtime; playgroundSites.getClient() returns that client after the site is ready.

Manage browser sites with window.playgroundSites

Use window.playgroundSites on the top-level https://playground.wordpress.net/ page. It is not available immediately during page load, so wait for the global and then call isReady() before site-manager work.

while (!window.playgroundSites) {
	await new Promise((resolve) => setTimeout(resolve, 50));
}
await window.playgroundSites.isReady();

Available site-manager operations:

• list(): inspect known sites, active site, names, slugs, and storage types.

• createNewTemporarySite(slug?, settings?): create and switch to a fresh in-memory site. Settings use phpVersion, wpVersion, networking, language, and multisite.

• setActiveSite(slug): switch to an existing site and wait for it to boot.

• isReady(): wait until the active site and its client are ready.

• getClient(): get the active site's PlaygroundClient.

• saveInBrowser(name?): persist the active site to OPFS browser storage.

• saveToLocalFileSystem(name?, handle?): persist the active site to a user-selected local directory when the browser supports it.

• rename(newName): rename the active saved site.

• setPhpVersion(version): change PHP version and reboot the active saved site.

• setNetworking(enabled): toggle outbound networking and reboot the active saved site.

• delete(slug): delete a saved site when the user explicitly asked for deletion.

Storage behavior:

• temporary: in memory only; resets on reload.

• opfs: saved in browser storage for playground.wordpress.net; survives reloads.

• local-fs: saved to a user-selected local directory; Chromium/File System Access API only.

Important constraints:

• createNewTemporarySite() accepts only version/site boot settings: phpVersion, wpVersion, networking, language, and multisite. The JS names are phpVersion and wpVersion, not php and wp.

• It does not install plugins/themes or run Blueprints; use a URL/Blueprint workflow for that.

• saveInBrowser() and saveToLocalFileSystem() are safe on already-saved sites.

• rename(), setPhpVersion(), and setNetworking() operate on the active saved site. Switch with setActiveSite(slug) first when targeting a specific site. Save a temporary site first.

• delete(slug) deletes a saved site's persisted data; do not call it unless the user asked for deletion.

Interact with the active WordPress site

Use the active PlaygroundClient after the site is booted. If the user says window.palyground, treat it as a typo for window.playground.

await window.playgroundSites?.isReady();
const client = window.playgroundSites?.getClient() || window.playground;
await client.isReady();

Available active-site operations:

• File inspection: listFiles, readFileAsText, readFileAsBuffer, fileExists, isFile, isDir, isSymlink, readlink, and realpath in the /wordpress virtual filesystem.

• File mutation: mkdir, mkdirTree, writeFile, mv, cp, chmod, symlink, unlink, rmdir, and unzip. mv moves or renames files. unlink deletes files, while playgroundSites.delete(slug) deletes a saved site. rmdir is for empty directories.

• PHP execution: run PHP snippets with run({ code }); inspect the returned output/status/error fields. Require /wordpress/wp-load.php before using WordPress APIs such as wp_insert_post, get_option, get_stylesheet, or wp_get_theme.

• Web requests: call WordPress routes with request({ path, method, headers, body }) and inspect status/body. Use it for admin pages such as /wp-admin/ and REST routes such as /wp-json/wp/v2/posts; remember admin/nonce behavior depends on login state.

• Browser navigation: send the visible Playground frame to a WordPress path with goTo(path).

• State checks: verify installed/active plugins and themes through WordPress PHP APIs or filesystem checks before claiming setup succeeded.

• MU plugins: write files under /wordpress/wp-content/mu-plugins/, then request or navigate to a WordPress route to force loading.

Keep the distinction clear:

• playgroundSites manages site records and persistence.

• window.playground / getClient() manipulates the active WordPress runtime.

• Query API / blueprint-url sets up a site at page load.

Verification

• Before changes, inspect window.playgroundSites.list() to confirm the intended active site.

• After site-manager operations, verify window.playgroundSites.list() shows the expected active site and storage type.

• For client operations, run a harmless read first, such as await client.listFiles('/wordpress'), before writing files or changing state. Verify the requested state after the operation.

• After switching sites or rebooting, wait for readiness and reacquire the active client before further operations.