function install_drupal

Installs Drupal either interactively or via an array of passed-in settings.

The Drupal installation happens in a series of steps, which may be spread out over multiple page requests. Each request begins by trying to determine the last completed installation step (also known as a "task"), if one is available from a previous request. Control is then passed to the task handler, which processes the remaining tasks that need to be run until (a) an error is thrown, (b) a new page needs to be displayed, or (c) the installation finishes (whichever happens first).

Parameters

$class_loader: The class loader. Normally Composer's ClassLoader, as included by the front controller, but may also be decorated; e.g., \Symfony\Component\ClassLoader\ApcClassLoader.

$settings: An optional array of installation settings. Leave this empty for a normal, interactive, browser-based installation intended to occur over multiple page requests. Alternatively, if an array of settings is passed in, the installer will attempt to use it to perform the installation in a single page request (optimized for the command line) and not send any output intended for the web browser. See install_state_defaults() for a list of elements that are allowed to appear in this array.

callable $callback: (optional) A callback to allow command line processes to update a progress bar. The callback is passed the $install_state variable.

See also

install_state_defaults()

File

core/includes/install.core.inc, line 104

Code

function install_drupal($class_loader, $settings = [], callable $callback = NULL) {
    global $install_state;
    // Initialize the installation state with the settings that were passed in,
    // as well as a boolean indicating whether or not this is an interactive
    // installation.
    $interactive = empty($settings);
    $install_state = $settings + [
        'interactive' => $interactive,
    ] + install_state_defaults();
    try {
        // Begin the page request. This adds information about the current state of
        // the Drupal installation to the passed-in array.
        install_begin_request($class_loader, $install_state);
        // Based on the installation state, run the remaining tasks for this page
        // request, and collect any output.
        $output = install_run_tasks($install_state, $callback);
    } catch (InstallerException $e) {
        // In the non-interactive installer, exceptions are always thrown directly.
        if (!$install_state['interactive']) {
            throw $e;
        }
        $output = [
            '#title' => $e->getTitle(),
            '#markup' => $e->getMessage(),
        ];
    }
    // After execution, all tasks might be complete, in which case
    // $install_state['installation_finished'] is TRUE. In case the last task
    // has been processed, remove the global $install_state, so other code can
    // reliably check whether it is running during the installer.
    // @see drupal_installation_attempted()
    $state = $install_state;
    if (!empty($install_state['installation_finished'])) {
        unset($GLOBALS['install_state']);
        // If installation is finished ensure any further container rebuilds do not
        // use the installer's service provider.
        unset($GLOBALS['conf']['container_service_providers']['InstallerServiceProvider']);
    }
    // All available tasks for this page request are now complete. Interactive
    // installations can send output to the browser or redirect the user to the
    // next page.
    if ($state['interactive']) {
        // If a session has been initiated in this request, make sure to save it.
        if (\Drupal::request()->hasSession()) {
            \Drupal::request()->getSession()
                ->save();
        }
        if ($state['parameters_changed']) {
            // Redirect to the correct page if the URL parameters have changed.
            install_goto(install_redirect_url($state));
        }
        elseif (isset($output)) {
            // Display a page only if some output is available. Otherwise it is
            // possible that we are printing a JSON page and theme output should
            // not be shown.
            install_display_output($output, $state);
        }
        elseif ($state['installation_finished']) {
            // Redirect to the newly installed site.
            $finish_url = '';
            if (isset($install_state['profile_info']['distribution']['install']['finish_url'])) {
                $finish_url = $install_state['profile_info']['distribution']['install']['finish_url'];
            }
            install_goto($finish_url);
        }
    }
}