如何在Drupal中缓存PHP生成的XML文件？

Question

I'm using ammap to display a map. On click, the user gets a list of latest Drupal 6 nodes tagged with the respective country (taxonomy). The list is generated by a view. To accomplish that, I use the basic ammap XML code, but I added some PHP to include the view, i.e.:

<?php
//set the working directory
chdir('..');
define('DRUPAL_ROOT', getcwd());

//Load Drupal
require_once './includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL); 

header ("Content-Type:text/xml");

?>

<map map_file="maps/world3.swf" tl_long="-117.2" tl_lat="33.3" br_long="-94.5" br_lat="-33.9" zoom="299.9999%" zoom_x="-30.94%" zoom_y="-156.8%">
  <areas>
      <!-- ... -->
      <area title="ARGENTINE" mc_name="AR">
        <description><![CDATA[<?php print views_embed_view('MY_VIEW', 'VIEW_DISPLAY_ID', 'ARGUMENT'); ?>]]></description>
      </area>
      <!-- ... -->
  </areas>
</map>

Now, since there are many tags that include a view, generating the XML file takes some moments which leads to long loading times for the map. For that reason I would like to cache the generated XML file somehow - taking into account that I need to add a path to it in the ammap configuration file.

How could I do that?

Answer 1

The best way to do, it is to write a small module.

Here's the shortest:

/**
 * Implement hook_menu()
 * to define path for our xml file.
 */
function mymodule_menu() {
    $items = array();
    $items['map.xml'] = array(
        'title' => 'Map xml',
        'page callback' => 'map_get_xml',
        'access arguments' => TRUE,
        'type' => MENU_CALLBACK
    );
    return $items;
}

/**
 * Your custom function for xml file.
 */
function map_get_xml() {
    $cache = cache_get('your-cache-id');
    $xml = $cache->data;

    if (!$xml) {
        $xml = ... // perform your code to generate your XML

        cache_set('your-cache-id', $xml);
    }

    drupal_set_header("Content-Type:text/xml");
    print $xml;
    exit();
}