example inject shell config

Inject data into openStationConfig

Add a feature flag + REST endpoint to the shell config so your TypeScript can read it without another rest_url() round-trip.

Plugin file

<?php
/**
 * Plugin Name: My Feature Flags
 */
defined( 'ABSPATH' ) || exit;

add_filter( 'openstation_shell_config', function ( $config ) {
    $config['myFeature'] = array(
        'enabled'  => (bool) get_option( 'my_ext_feature_enabled' ),
        'endpoint' => esc_url_raw( rest_url( 'my-ext/v1/stats' ) ),
        'role'     => wp_get_current_user()->roles[0] ?? 'subscriber',
    );
    return $config;
} );

Reading from JS

document.addEventListener( 'os-init', () => {
    const cfg = window.openStationConfig;
    if ( ! cfg.myFeature?.enabled ) {
        return;
    }
    fetch( cfg.myFeature.endpoint, {
        credentials: 'same-origin',
    } )
        .then( ( r ) => r.json() )
        .then( ( data ) => console.log( 'stats', data ) );
} );

Guidelines

• Namespace your keys. Use myFeature, myExtSomething — avoid generic names like flags or config that could collide with another plugin.
• Always JSON-safe. The config is JSON-encoded into a <script> block. Don't put resources, closures, or unserializable objects in it.
• Don't put secrets. The config is readable by anyone with access to the page. Use nonces for REST calls rather than trying to embed API keys.
• Keep it small. Everything here ships on every shell page-load.

Related

• Hooks Reference — openstation_shell_config
• JavaScript Reference — os-init