captcha_questions.module in Captcha Questions 8

Module file for the Captcha questions module.

The module hooks into forms and adds a configurable question field and a custom validate function returning an error if the answer is wrong.

File

captcha_questions.module

<?php

/**
 * @file
 * Module file for the Captcha questions module.
 *
 * The module hooks into forms and adds a configurable question field and a
 * custom validate function returning an error if the answer is wrong.
 */
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Component\Utility\Html;

/**
 * Implements hook_help().
 */
function captcha_questions_help($route_name, RouteMatchInterface $route_match) {
  if ($route_name == 'help.page.captcha_questions') {
    return t('Captcha questions allows the site administrator to add a question to selected forms');
  }
}

/**
 * Implements hook_form_alter().
 */
function captcha_questions_form_alter(&$form, FormStateInterface $form_state, $form_id) {

  // Only show captcha questions if user is anonymous.
  if (\Drupal::currentUser()
    ->isAnonymous()) {

    // Fetching variables for form ids, question and description.
    $config = \Drupal::config('captcha_questions.settings');
    $captcha_questions_form_ids = $config
      ->get('captcha_questions_form_ids');
    $question = $config
      ->get('captcha_questions_question');
    $description = $config
      ->get('captcha_questions_description');
    if (in_array($form_id, $captcha_questions_form_ids)) {

      // If we're on a multi page form, find current page.
      $form_page_count = isset($form['details']['page_num']['#value']) ? $form['details']['page_num']['#value'] : 1;

      // Set field to hidden unless on the first page.
      $form['captcha_questions_answer_given'] = [
        '#type' => $form_page_count == 1 ? 'textfield' : 'hidden',
        '#description' => t("@description", [
          '@description' => $description,
        ]),
        '#title' => Html::escape($question),
        '#size' => 60,
        '#required' => TRUE,
      ];
      $form['#validate'][] = 'captcha_questions_form_validate';
    }
    return $form;
  }
}

/**
 * Implements hook_form_validate().
 */
function captcha_questions_form_validate(&$form, FormStateInterface $form_state) {
  $ip = \Drupal::request()
    ->getClientIp();
  $form_id = $form_state
    ->getValue('form_id');
  $config = \Drupal::config('captcha_questions.settings');
  $question_asked = $config
    ->get('captcha_questions_question');
  $answers = $config
    ->get('captcha_questions_answers');
  $answer_given = $form_state
    ->getValue('captcha_questions_answer_given');

  // Comparison is done in lowercase, ensure answers are lowercase.
  $answers = array_map('strtolower', $answers);
  $answer_given = mb_strtolower($answer_given);

  // Check answer.
  if (in_array($answer_given, $answers) == FALSE) {

    // Log to watchdog if enabled.
    if ($config
      ->get('captcha_questions_watchdog')) {
      $message = t('Blocked submission of form with form_id @form_id. Answer given was %answer_given', [
        '@form_id' => $form_id,
        '%answer_given' => $form_state
          ->getValue('captcha_questions_answer_given'),
      ]);
      \Drupal::logger('captcha_questions')
        ->error($message);
    }

    // Log to dblog if enabled and module exists and enabled.
    $dblog_enabled = \Drupal::config('captcha_questions.settings')
      ->get('captcha_questions_dblog');
    $dblog_module_exists = \Drupal::moduleHandler()
      ->moduleExists('captcha_questions_dblog') ? TRUE : FALSE;
    if ($dblog_enabled && $dblog_module_exists) {
      \Drupal::database()
        ->insert('captcha_questions_dblog')
        ->fields([
        'timestamp' => \Drupal::time()
          ->getRequestTime(),
        'ip' => $ip,
        'form_id' => $form_id,
        'question_asked' => Html::escape($question_asked),
        'answer_given' => Html::escape($answer_given),
        'answer_correct' => implode(",", $answers),
      ])
        ->execute();
    }

    // Display error.
    $form_state
      ->setErrorByName('captcha_questions_answer_given', t('Invalid answer'));
  }
}

Functions

Name	Description
captcha_questions_form_alter	Implements hook_form_alter().
captcha_questions_form_validate	Implements hook_form_validate().
captcha_questions_help	Implements hook_help().