function install_run_task

Runs an individual installation task.

Parameters

$task: An array of information about the task to be run.

$install_state: An array of information about the current installation state. This is passed in by reference so that it can be modified by the task.

Return value

The output of the task function, if there is any.

File

drupal/core/includes/install.core.inc, line 464

API functions for installing Drupal.

Code

function install_run_task($task, &$install_state) {
  $function = $task['function'];
  if ($task['type'] == 'form') {
    require_once DRUPAL_ROOT . '/core/includes/form.inc';
    if ($install_state['interactive']) {

      // For interactive forms, build the form and ensure that it will not
      // redirect, since the installer handles its own redirection only after
      // marking the form submission task complete.
      $form_state = array(
        // We need to pass $install_state by reference in order for forms to
        // modify it, since the form API will use it in call_user_func_array(),
        // which requires that referenced variables be passed explicitly.
        'build_info' => array(
          'args' => array(
            &$install_state,
          ),
        ),
        'no_redirect' => TRUE,
      );
      $form = drupal_build_form($function, $form_state);

      // If a successful form submission did not occur, the form needs to be
      // rendered, which means the task is not complete yet.
      if (empty($form_state['executed'])) {
        $install_state['task_not_complete'] = TRUE;
        return drupal_render($form);
      }

      // Otherwise, return nothing so the next task will run in the same
      // request.
      return;
    }
    else {

      // For non-interactive forms, submit the form programmatically with the
      // values taken from the installation state. Throw an exception if any
      // errors were encountered.
      $form_state = array(
        'values' => !empty($install_state['forms'][$function]) ? $install_state['forms'][$function] : array(),
        // We need to pass $install_state by reference in order for forms to
        // modify it, since the form API will use it in call_user_func_array(),
        // which requires that referenced variables be passed explicitly.
        'build_info' => array(
          'args' => array(
            &$install_state,
          ),
        ),
      );
      drupal_form_submit($function, $form_state);
      $errors = form_get_errors();
      if (!empty($errors)) {
        throw new Exception(implode("\n", $errors));
      }
    }
  }
  elseif ($task['type'] == 'batch') {

    // Start a new batch based on the task function, if one is not running
    // already.
    $current_batch = variable_get('install_current_batch');
    if (!$install_state['interactive'] || !$current_batch) {
      $batch = $function($install_state);
      if (empty($batch)) {

        // If the task did some processing and decided no batch was necessary,
        // there is nothing more to do here.
        return;
      }
      batch_set($batch);

      // For interactive batches, we need to store the fact that this batch
      // task is currently running. Otherwise, we need to make sure the batch
      // will complete in one page request.
      if ($install_state['interactive']) {
        variable_set('install_current_batch', $function);
      }
      else {
        $batch =& batch_get();
        $batch['progressive'] = FALSE;
      }

      // Process the batch. For progressive batches, this will redirect.
      // Otherwise, the batch will complete.
      batch_process(install_redirect_url($install_state), install_full_redirect_url($install_state));
    }
    elseif ($current_batch == $function) {
      include_once DRUPAL_ROOT . '/core/includes/batch.inc';
      $output = _batch_page();

      // Because Batch API now returns a JSON response for intermediary steps,
      // but the installer doesn't handle Response objects yet, just send the
      // output here and emulate the old model.
      // @todo Replace this when we refactor the installer to use a request-
      //   response workflow.
      if ($output instanceof Response) {
        $output
          ->send();
        $output = NULL;
      }

      // The task is complete when we try to access the batch page and receive
      // FALSE in return, since this means we are at a URL where we are no
      // longer requesting a batch ID.
      if ($output === FALSE) {

        // Return nothing so the next task will run in the same request.
        variable_del('install_current_batch');
        return;
      }
      else {

        // We need to force the page request to end if the task is not
        // complete, since the batch API sometimes prints JSON output
        // rather than returning a themed page.
        $install_state['task_not_complete'] = $install_state['stop_page_request'] = TRUE;
        return $output;
      }
    }
  }
  else {

    // For normal tasks, just return the function result, whatever it is.
    return $function($install_state);
  }
}