GET access argument

get.inc

<?php
/**
 * @file
 * Plugin to provide access control/visibility based on specified get argument matching user-specified string
 */

$plugin = array(
  'title' => t("GET: comparison"),
  'description' => t('Control access by comparing a GET argument.'),
  'callback' => 'ctools_get_ctools_access_check',
  'settings form' => 'ctools_get_ctools_access_settings',
  'summary' => 'ctools_get_ctools_access_summary',
  //'required context' => new ctools_context_required(t('String'), 'string'),
  'defaults' => array('operator' => '=', 'value' => '', 'case' => FALSE),
);

/**
 * Settings form
 */
function ctools_get_ctools_access_settings(&$form, &$form_state, $conf) {
  $form['settings']['operator'] = array(
    '#type' => 'select',
    '#title' => t('Operator'),
    '#options' => array(
      'isset' => t('Is set'),
      '=' => t('Equal'),
      '!=' => t('Not equal'),
      'regex' => t('Regular expression'),
      '!regex' => t('Not equal to regular expression'),
    ),
    '#default_value' => $conf['operator'],
    '#id' => 'ctools-select-operator',
    '#description' => t('If using a regular expression, you should enclose the pattern in slashes like so: <em>/foo/</em>. If you need to compare against slashes you can use another character to enclose the pattern, such as @. See <a href="http://www.php.net/manual/en/reference.pcre.pattern.syntax.php">PHP regex documentation</a> for more.'),
  );

  $form['settings']['argument'] = array(
    '#type' => 'textfield',
    '#title' => t('Argument'),
    '#default_value' => $conf['argument'],
  );

  ctools_include('dependent');
  $form['settings']['value'] = array(
    '#type' => 'textfield',
    '#title' => t('Value'),
    '#default_value' => $conf['value'],
    '#process' => array('ctools_dependent_process'),
    '#dependency' => array('ctools-select-operator' => array('=', '!=', 'regex', '!regex')),
  );

  $form['settings']['case'] = array(
    '#type' => 'checkbox',
    '#title' => t('Case sensitive'),
    '#default_value' => $conf['case'],
  );
}

/**
 * Check for access
 */
function ctools_get_ctools_access_check($conf, $context) {

  $argument = isset($_GET[$conf['argument']]) ? $_GET[$conf['argument']] : '';
  $value = $conf['value'];
  if (empty($conf['case'])) {
    $argument = drupal_strtolower($argument);
    $value = drupal_strtolower($value);
  }

  switch ($conf['operator']) {
    case 'isset':
      return isset($_GET[$conf['argument']]);
    case '=':
      return $argument === $value;
    case '!=':
      return $argument !== $value;
    case 'regex':
      return preg_match($value, $argument);
    case '!regex':
      return !preg_match($value, $argument);
  }
}

/**
 * Provide a summary description based upon the specified context
 */
function ctools_get_ctools_access_summary($conf, $context) {
  $values = array('@identifier' => $conf['argument'], '@value' => $conf['value']);
  switch ($conf['operator']) {
    case 'isset':
      return t('GET argument @identifier is set', $values);
    case '=':
      return t('GET argument @identifier is "@value"', $values);
    case '!=':
      return t('GET argument @identifier is not "@value"', $values);
    case 'regex':
      return t('GET argument @identifier matches "@value"', $values);
    case '!regex':
      return t('GET argument @identifier does not match "@value"', $values);
  }
}