grav-multisite.php

 /**
 * Multisite setup for subsites accessible via sub-domains.
 *
 * DO NOT EDIT UNLESS YOU KNOW WHAT YOU ARE DOING!
 */

use Grav\Common\Utils;

// Get subsite name from sub-domain
$environment = isset($_SERVER['HTTP_HOST'])
    ? $_SERVER['HTTP_HOST']
    : (isset($_SERVER['SERVER_NAME']) ? $_SERVER['SERVER_NAME'] : 'localhost');
// Remove port from HTTP_HOST generated $environment
$environment = strtolower(Utils::substrToString($environment, ':'));
$folder = "sites/{$environment}";

$themes = ["user/themes"];
if (is_dir(__DIR__ . "/user/{$folder}/themes")) {
    array_unshift($themes, "user/{$folder}/themes");
}

$plugins = ["user/plugins"];
if (is_dir(__DIR__ . "/user/{$folder}/plugins")) {
    array_unshift($themes, "user/{$folder}/plugins");
}

if ($environment === 'localhost' || !is_dir(ROOT_DIR . "user/{$folder}")) {
    return [];
}

return [
    'environment' => $environment,
    'streams' => [
        'schemes' => [
            'user' => [
               'type' => 'ReadOnlyStream',
               'prefixes' => [
                   '' => ["user/{$folder}"],
               ]
            ],
            'environment' => [
                'type' => 'ReadOnlyStream',
                'prefixes' => [
                    '' => ["user/{$folder}"],
                ]
            ],
            'themes' => [
                'type' => 'ReadOnlyStream',
                'prefixes' => [
                    '' => $themes
                ]
            ],
            'plugins' => [
                'type' => 'ReadOnlyStream',
                'prefixes' => [
                    '' => $plugins
                ]
            ],
            'plugin' => [
                'type' => 'ReadOnlyStream',
                'prefixes' => [
                    '' => ['plugins://']
                ]
            ]
        ]
    ]
];