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Diffstat (limited to 'user_guide_src/source/helpers/captcha_helper.rst')
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diff --git a/user_guide_src/source/helpers/captcha_helper.rst b/user_guide_src/source/helpers/captcha_helper.rst deleted file mode 100644 index be1b20aaf..000000000 --- a/user_guide_src/source/helpers/captcha_helper.rst +++ /dev/null @@ -1,168 +0,0 @@ -############## -CAPTCHA Helper -############## - -The CAPTCHA Helper file contains functions that assist in creating -CAPTCHA images. - -.. contents:: - :local: - -.. raw:: html - - <div class="custom-index container"></div> - -Loading this Helper -=================== - -This helper is loaded using the following code:: - - $this->load->helper('captcha'); - -Using the CAPTCHA helper -======================== - -Once loaded you can generate a CAPTCHA like this:: - - $vals = array( - 'word' => 'Random word', - 'img_path' => './captcha/', - 'img_url' => 'http://example.com/captcha/', - 'font_path' => './path/to/fonts/texb.ttf', - 'img_width' => '150', - 'img_height' => 30, - 'expiration' => 7200, - 'word_length' => 8, - 'font_size' => 16, - 'img_id' => 'Imageid', - 'pool' => '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', - - // White background and border, black text and red grid - 'colors' => array( - 'background' => array(255, 255, 255), - 'border' => array(255, 255, 255), - 'text' => array(0, 0, 0), - 'grid' => array(255, 40, 40) - ) - ); - - $cap = create_captcha($vals); - echo $cap['image']; - -- The captcha function requires the GD image library. -- Only the **img_path** and **img_url** are required. -- If a **word** is not supplied, the function will generate a random - ASCII string. You might put together your own word library that you - can draw randomly from. -- If you do not specify a path to a TRUE TYPE font, the native ugly GD - font will be used. -- The "captcha" directory must be writable -- The **expiration** (in seconds) signifies how long an image will remain - in the captcha folder before it will be deleted. The default is two - hours. -- **word_length** defaults to 8, **pool** defaults to '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' -- **font_size** defaults to 16, the native GD font has a size limit. Specify a "true type" font for bigger sizes. -- The **img_id** will be set as the "id" of the captcha image. -- If any of the **colors** values is missing, it will be replaced by the default. - -Adding a Database ------------------ - -In order for the captcha function to prevent someone from submitting, -you will need to add the information returned from ``create_captcha()`` -to your database. Then, when the data from the form is submitted by -the user you will need to verify that the data exists in the database -and has not expired. - -Here is a table prototype:: - - CREATE TABLE captcha ( - captcha_id bigint(13) unsigned NOT NULL auto_increment, - captcha_time int(10) unsigned NOT NULL, - ip_address varchar(45) NOT NULL, - word varchar(20) NOT NULL, - PRIMARY KEY `captcha_id` (`captcha_id`), - KEY `word` (`word`) - ); - -Here is an example of usage with a database. On the page where the -CAPTCHA will be shown you'll have something like this:: - - $this->load->helper('captcha'); - $vals = array( - 'img_path' => './captcha/', - 'img_url' => 'http://example.com/captcha/' - ); - - $cap = create_captcha($vals); - $data = array( - 'captcha_time' => $cap['time'], - 'ip_address' => $this->input->ip_address(), - 'word' => $cap['word'] - ); - - $query = $this->db->insert_string('captcha', $data); - $this->db->query($query); - - echo 'Submit the word you see below:'; - echo $cap['image']; - echo '<input type="text" name="captcha" value="" />'; - -Then, on the page that accepts the submission you'll have something like -this:: - - // First, delete old captchas - $expiration = time() - 7200; // Two hour limit - $this->db->where('captcha_time < ', $expiration) - ->delete('captcha'); - - // Then see if a captcha exists: - $sql = 'SELECT COUNT(*) AS count FROM captcha WHERE word = ? AND ip_address = ? AND captcha_time > ?'; - $binds = array($_POST['captcha'], $this->input->ip_address(), $expiration); - $query = $this->db->query($sql, $binds); - $row = $query->row(); - - if ($row->count == 0) - { - echo 'You must submit the word that appears in the image.'; - } - -Available Functions -=================== - -The following functions are available: - -.. php:function:: create_captcha([$data = ''[, $img_path = ''[, $img_url = ''[, $font_path = '']]]]) - - :param array $data: Array of data for the CAPTCHA - :param string $img_path: Path to create the image in (DEPRECATED) - :param string $img_url: URL to the CAPTCHA image folder (DEPRECATED) - :param string $font_path: Server path to font (DEPRECATED) - :returns: array('word' => $word, 'time' => $now, 'image' => $img) - :rtype: array - - Takes an array of information to generate the CAPTCHA as input and - creates the image to your specifications, returning an array of - associative data about the image. - - :: - - array( - 'image' => IMAGE TAG - 'time' => TIMESTAMP (in microtime) - 'word' => CAPTCHA WORD - ) - - The **image** is the actual image tag:: - - <img src="http://example.com/captcha/12345.jpg" width="140" height="50" /> - - The **time** is the micro timestamp used as the image name without the - file extension. It will be a number like this: 1139612155.3422 - - The **word** is the word that appears in the captcha image, which if not - supplied to the function, will be a random string. - - .. note:: Usage of the ``$img_path``, ``$img_url`` and ``$font_path`` - parameters is DEPRECATED. Provide them in the ``$data`` array - instead. |