google_appliance_suggest_callback.php

<?php

/**
 * @file 
 * The callback for the Google Appliance Suggest module's autocomplete.
 *
 * We do this rather than a Drupal menu callback to use as lightweight a Drupal
 * bootstrap as possible.
 */


// Try and load Drupal's bootstrap.inc.
define('DRUPAL_ROOT', $_SERVER['DOCUMENT_ROOT']);
require_once DRUPAL_ROOT . '/includes/bootstrap.inc';
require_once DRUPAL_ROOT . '/includes/common.inc';

// Bootstrap Drupal to the variables stage.
if (function_exists('drupal_bootstrap')) {
  drupal_bootstrap(DRUPAL_BOOTSTRAP_VARIABLES);
  $gsa_suggest_cache = variable_get('google_appliance_suggest_cache', 1);

  // Attempt to pull the query from cache.
  $cache = drupal_page_get_cache();
  if ($gsa_suggest_cache && is_object($cache)) {
    header('X-Drupal-Cache: HIT');
    drupal_serve_page_from_cache($cache);
    exit();
  }

  // Now that we're in Drupal, pull some configuration values.
  $gsa_hostname = variable_get('google_appliance_hostname', FALSE);
  $gsa_timeout = variable_get('google_appliance_timeout', 10);
  $gsa_collection = variable_get('google_appliance_collection', 'default_collection');
  $gsa_frontend = variable_get('google_appliance_frontend', 'default_frontend');
  $gsa_max_autosuggest = variable_get('google_appliance_suggest_max', 5);

  // Make sure we have a valid GSA host to connect to.
  if ($gsa_hostname) {
    // Build the search term to pass to GSA
    $search_query = $_GET['q'];

    // Create a list of query parameters from configurations.
    $get = array(
      'q' => $search_query,
      'max' => $gsa_max_autosuggest,
      'site' => $gsa_collection,
      'client' => $gsa_frontend,
      'access' => 'p',
      'format' => 'os',
    );

    // Fire off the GET request.
    $curl_defaults = array(
      CURLOPT_URL => $gsa_hostname . '/suggest?' . http_build_query($get, '', '&'),
      CURLOPT_HEADER => 0,
      CURLOPT_RETURNTRANSFER => TRUE,
      CURLOPT_TIMEOUT => check_plain($gsa_timeout)
    );

    // Use drupal proxy if any.
    $drupal_proxy_server = variable_get('proxy_server', '');
    $drupal_proxy_port = variable_get('proxy_port', '');
    $drupal_proxy_username = variable_get('proxy_username', '');
    $drupal_proxy_password = variable_get('proxy_password', '');
    $drupal_proxy_user_agent = variable_get('proxy_user_agent', NULL); // NULL as default value
    $drupal_proxy_exceptions = variable_get('proxy_exceptions', array());

    // Add drupal proxy to curl_defaults.
    if ($drupal_proxy_server != '') {
        // Parse gsa_hostname to obtain the host without the scheme (http/https).
        // Check if a proxy should be used for gsa_hostname using _drupal_http_use_proxy
        // If parsing fails (and it should not), use the proxy. The idea here is that we should always use the proxy
        // except for some exceptional hosts. If we are not able to confirm that this is indeed an exception
        // better to use the proxy.
        $gsa_hostname_components = @parse_url($gsa_hostname);
        if ($gsa_hostname_components === false || _drupal_http_use_proxy($gsa_hostname_components['host'])) {
            $curl_defaults[CURLOPT_PROXY] = $drupal_proxy_server;
            // Add port, if provided.
            if ($drupal_proxy_port != '') {
                $curl_defaults[CURLOPT_PROXY] .= ':' . $drupal_proxy_port;
            }

            // Some proxies reject requests with any User-Agent headers, while others
            // require a specific one.
            if ($drupal_proxy_user_agent !== NULL) {
                $curl_defaults[CURLOPT_USERAGENT] = $drupal_proxy_user_agent;
            }
        }

        // Set authentication, if needed, checking if proxy_username is not empty.
        if ($drupal_proxy_username != '') {
            // The option CURLOPT_PROXYUSERPWD has format [username]:[password].
            $curl_defaults[CURLOPT_PROXYUSERPWD] = $drupal_proxy_username . ':' . $drupal_proxy_password;
        }
    }

    $ch = curl_init();
    curl_setopt_array($ch, $curl_defaults);
    $result = array(
      'is_error' => FALSE,
      'response' => curl_exec($ch),
    );

    // If we got a valid response, cache it and print it.
    if ($result['response'] !== FALSE) {
      // Format JSON to what Drupal expects on autocomplete.
      $json_source = drupal_json_decode($result['response']);
      $response = array();
      if (isset($json_source[1])  && is_array($json_source[1])) {
        $strong = '<strong>' . $search_query . '</strong>';
        foreach ($json_source[1] as $item) {
          $response[$item] = str_replace($search_query, $strong, $item);
        }

        // Prepare content for caching and display it.
        ob_start();
        drupal_json_output($response);
        if ($gsa_suggest_cache) {
          header('X-Drupal-Cache: MISS');
          $cache = drupal_page_set_cache();
          drupal_serve_page_from_cache($cache);
        }
      }
      else {
        drupal_json_output(array());
      }
    }
    else {
      drupal_json_output(array());
    }

    curl_close($ch);
  }
}
else {
  // Fallback to returning nothing.
  drupal_json_output(array());
}