diff --git a/textcaptcha.install b/textcaptcha.install new file mode 100644 index 0000000..9dee928 --- /dev/null +++ b/textcaptcha.install @@ -0,0 +1,47 @@ + l('here', 'http://textcaptcha.com/'), + '!admin' => l('here', 'admin/config/people/captcha/textcaptcha'), + ) + ); + drupal_set_message($text, 'warning'); +} + +/** + * Implements hook_update_N(). + */ +function textcaptcha_update_7001() { + // Update captcha limit. There was a bug, restricting cache limit to 0, 1, 2, + // 3, or 4 (when users were selecting 0, 10, 20, 30, 40). + $limit = variable_get('textcaptcha_cache_limit', 0); + switch ($limit) { + case 0: + case 1: + variable_set('textcaptcha_cache_limit', 10); + break; + case 2: + variable_set('textcaptcha_cache_limit', 20); + break; + case 3: + variable_set('textcaptcha_cache_limit', 30); + break; + case 4: + variable_set('textcaptcha_cache_limit', 40); + break; + } + + // Populate cache with some challenges. + for ($i = 0; $i < 10; $i++) { + if ($challenge = textcaptcha_get_new_challenge()) { + textcaptcha_cache_new_challenge($challenge); + } + } +} diff --git a/textcaptcha.module b/textcaptcha.module index d9273a7..a272a00 100644 --- a/textcaptcha.module +++ b/textcaptcha.module @@ -1,4 +1,4 @@ - 'select', - '#title' => t('Number of challenges to keep as backup'), - '#description' => t('If you cannot contact textcaptcha.com or the service is unavailable, some challenges are kept in the site cache as backup. Select zero to turn this feature off.'), - '#options' => array( - 0, - 10, - 20, - 30, - 40 - ), - '#default_value' => variable_get('textcaptcha_cache_limit', 10), + '#type' => 'textfield', + '#title' => t('Number of challenges to keep cached locally'), + '#description' => t('TextCAPTCHA calls a web service on cron runs to retrieve new challenge questions. This number determines how many challenges to keep cached at a time.'), + '#default_value' => variable_get('textcaptcha_cache_limit', 30), + ); + + $form['textcaptcha_cron'] = array( + '#type' => 'checkbox', + '#title' => t('Fetch questions on cron'), + '#description' => t('Enable or disable fetching and processing questions on cron.'), + '#default_value' => variable_get('textcaptcha_cron', 1), + ); + + $form['actions']['text_captcha'] = array( + '#type' => 'submit', + '#value' => t('Retrieve new captcha challenges'), + '#submit' => array('textcaptcha_get_new_challenges'), ); return system_settings_form($form); } /** + * Get new challenge questions and cache them. + */ +function textcaptcha_get_new_challenges() { + $success = 0; + for ($i = 0; $i < 10; $i++) { + if ($challenge = textcaptcha_get_new_challenge()) { + textcaptcha_cache_new_challenge($challenge); + $success++; + } + } + + if ($success < 1) { + $text = t('Sorry. After trying !i times, I was unable to retrieve any new + challenge questions. Either your API key is bad, you are not online, or the + web service you are trying to reach is not responding.', array('!i' => $i)); + drupal_set_message($text, 'warning'); + } + else { + $text = t('Success! You have !success new challenge questions. (!success/!i + attempts to retrieve new challenge questions were successful.)', + array( + '!success' => $success, + '!i' => $i, + ) + ); + drupal_set_message($text, 'success'); + } + + $count = textcaptcha_cache_count(); + $text = t('You have !count cached challenge questions.', array('!count' => $count)); + if ($count < 10) { + $status = 'warning'; + } + else { + $status = 'notice'; + } + drupal_set_message($text, $status); +} + +/** * Form validation for admin settings. Here we check that the API key works. */ function textcaptcha_settings_form_validate($form, $form_state) { - $result = drupal_http_request(TEXTCAPTCHA_URL_PREFIX . trim($form_state['values']['textcaptcha_api_key'])); + $result = textcaptcha_http_request(); if ($result->code !== '200') { form_set_error('textcaptcha_api_key', t('The API Key did not work or the server cannot contact textcaptcha.com')); } @@ -80,10 +126,10 @@ function textcaptcha_captcha($op, $captcha_type='') { case 'generate' : $result = array(); if ($captcha_type == 'Text Captcha') { - $textcaptcha = textcaptcha_get_captcha(); + $challenge = textcaptcha_get_challenge(); $result['form']['captcha_response'] = array( '#type' => 'textfield', - '#title' => $textcaptcha['question'], + '#title' => $challenge['question'], '#description' => t('Question text provided by !link', array('!link' => l('textcaptcha.com', 'http://textcaptcha.com')) ), @@ -91,7 +137,7 @@ function textcaptcha_captcha($op, $captcha_type='') { '#maxlength' => 50, '#required' => TRUE, ); - $result['solution'] = serialize($textcaptcha['answers']); + $result['solution'] = serialize($challenge['answers']); $result['captcha_validate'] = 'textcaptcha_captcha_validate'; return $result; @@ -101,43 +147,42 @@ function textcaptcha_captcha($op, $captcha_type='') { } /** -* Retrieves CAPTCHA and possible answer list from the textcaptcha.com service -*/ -function textcaptcha_get_captcha($use_cache = TRUE) { - if (variable_get('textcaptcha_cache_limit', 10) == 0) { - $use_cache = FALSE; - } - if (variable_get('textcaptcha_api_key', FALSE)) { - $cached_challenges = cache_get('textcaptcha_cached_challenges'); - $captcha = drupal_http_request(TEXTCAPTCHA_URL_PREFIX . trim(variable_get('textcaptcha_api_key', ''))); - if ($captcha->code == '200' && $captcha->data) { - $parser = drupal_xml_parser_create($captcha->data); - $captcha_xml = array(); - xml_parse_into_struct($parser, $captcha->data, $captcha_xml); - $answers = array(); - foreach ($captcha_xml as $element) { - if ($element['tag'] == 'QUESTION' && $element['type'] == 'complete') { - $question = $element['value']; - } - if ($element['tag'] == 'ANSWER' && $element['type'] == 'complete') { - $answers[] = $element['value']; - } - } - $cached_challenges->data[] = array('question' => $question, - 'answers' => $answers); - if (count($cached_challenges->data) > variable_get('textcaptcha_cache_limit', 10)) { - array_shift($cached_challenges->data); - } - if ($use_cache) { - cache_set('textcaptcha_cached_challenges', $cached_challenges->data); - } - return array('question' => $question, 'answers' => $answers); - } - elseif ($cached_challenges && $use_cache) { - return array_rand($cached_challenges->data); + * Retrieves CAPTCHA and possible answer list from the textcaptcha.com service + * + * @return array $challenge + * @see textcaptcha_parse_data(). + */ +function textcaptcha_get_challenge() { + $challenge = array(); + + if (!$key = variable_get('textcaptcha_api_key', FALSE)) { + return FALSE; + } + + // Try to retreive a cached captcha challenge question. + if ($cache = cache_get('textcaptcha_challenges')) { + $challenges = array_filter($cache->data); + $key = array_rand($challenges); + $challenge = $challenges[$key]; + } + else { + // If no cached challenges are available try and get one on the fly + // from web service. + $challenge = textcaptcha_get_new_challenge(); + if ($challenge) { + textcaptcha_cache_new_challenge($challenge); } } - return FALSE; + + // Handle empty response. + if (!$challenge) { + $text = t("Sorry. Something went wrong. This CAPTCHA won't work. Please reload your page."); + drupal_set_message($text, 'warning'); + $challenge['question'] = $text; + $challenge['answers'] = array(); + } + + return $challenge; } /** @@ -176,4 +221,126 @@ function textcaptcha_requirements($phase) { } } return $requirements; -} \ No newline at end of file +} + +/** + * @param array $data + * Data from a successful drupal_http_request() call to textcaptcha.com API + * + * @return array $challenge + * Return array including challenge and md5 hash of valid answers. + * e.g. $challenge( + * 'question' => 'What color is the sky?', + * 'answers' => array('c9f0f895f', '24d27c169'), + * ); + */ +function textcaptcha_parse_data($data) { + $parser = drupal_xml_parser_create($data); + $captcha_xml = array(); + xml_parse_into_struct($parser, $data, $captcha_xml); + + $challenge = array(); + foreach ($captcha_xml as $element) { + if ($element['tag'] == 'QUESTION' && $element['type'] == 'complete') { + $challenge['question'] = $element['value']; + } + if ($element['tag'] == 'ANSWER' && $element['type'] == 'complete') { + $challenge['answers'][] = $element['value']; + } + } + + return $challenge; +} + +/** + * Implements hook_cron(). + * + * Every time cron runs it checks for a new challenge question to add to the + * cache. If there 100 cached challenges, drop the oldest. + * + */ +function textcaptcha_cron() { + if (variable_get('textcaptcha_cron', 1)) { + $challenge = textcaptcha_get_new_challenge(); + textcaptcha_cache_new_challenge($challenge); + } +} + +/** + * Cache new challenge question. + * + * @param array $challenge + * @see textcaptcha_parse_data(). + */ +function textcaptcha_cache_new_challenge($challenge) { + // Store challenge with other cached challenges. + if ($cache = cache_get('textcaptcha_challenges')) { + $data = $cache->data; + // If the cache is full, remove the oldest, to be replaced with the new one. + $limit = variable_get('textcaptcha_cache_limit', 50); + $limit = (is_int($limit)) ? $limit : 50; + if (count($data) > $limit) { + array_shift($data); + } + $data[] = $challenge; + } + else { + $data = array($challenge); + } + // Use array_filter in case there are empty elements in $data. + $data = array_filter($data); + cache_set('textcaptcha_challenges', $data); +} + +/** + * Return count of cached challenge questions. + */ +function textcaptcha_cache_count() { + if ($cache = cache_get('textcaptcha_challenges')) { + $data = $cache->data; + $count = count($data); + } + else { + $count = 0; + } + return $count; +} + +/** + * Retrieve a new challenge from textcaptcha web service and cache it. + * + * @return + * $challenge array or FALSE + */ +function textcaptcha_get_new_challenge() { + // Attempt to retrieve a new challenge from the web service. + $success = FALSE; + for ($i = 1; $i <= 10; $i++) { + $response = textcaptcha_http_request(); + if (!$response->code == 200) { + // We didn't get a successful response. Log failed attempt. + $text = t('Failed attempt !n to get textcaptcha question from !api.', array('!n' => $i, '!api' => TEXTCAPTCHA_URL_PREFIX)); + watchdog('textcaptcha', $text); + } + else { + // Log success. + $success = TRUE; + $text = t('Successfully retrieved new textcaptcha challenge question on attempt !n', array('!n' => $i)); + watchdog('textcaptcha', $text); + break; + } + } + + return ($success) ? textcaptcha_parse_data($response->data) : FALSE; +} + +/** + * Wrapper around textcaptcha API call. + * + * @return array + * Response from drupal_http_request() to textcaptcha web service. + */ +function textcaptcha_http_request() { + $response = drupal_http_request(TEXTCAPTCHA_URL_PREFIX . trim(variable_get('textcaptcha_api_key', ''))); + return $response; +}