/**
* Generates the RSS Feed
*
* @param strClass $context the context the feed should be created under
* @param array $args array of arguments to be used in the creation of the RSS Feed
* @return NULL|string NULL if there is nothing to return, or the file path of the cached file if there is
*/
function dataform_rss_get_feed($context, $args)
{
global $CFG, $DB;
// Check CFG->data_enablerssfeeds.
if (empty($CFG->dataform_enablerssfeeds)) {
debugging("DISABLED (module configuration)");
return null;
}
// Validate context.
$dataformid = clean_param($args[3], PARAM_INT);
$cm = get_coursemodule_from_instance('dataform', $dataformid, 0, false, MUST_EXIST);
if ($cm) {
$modcontext = context_module::instance($cm->id);
// Context id from db should match the submitted one.
if ($context->id != $modcontext->id) {
return null;
}
}
// Check RSS enbabled for instance.
$dataform = $DB->get_record('dataform', array('id' => $dataformid), '*', MUST_EXIST);
if (!rss_enabled_for_mod('dataform', $dataform, false, false)) {
return null;
}
// Get the target view.
$viewid = clean_param($args[4], PARAM_INT);
$viewdata = $DB->get_record('dataform_views', array('id' => $viewid), '*', MUST_EXIST);
$viewman = mod_dataform_view_manager::instance($dataformid);
$view = $viewman->get_view_by_id($viewid);
// If (!($view instanceof 'mod_dataform\interfaces\rss')) {
// return null;
// }.
// Get the cache file info
// The cached file name is formatted dfid_viewid_contentstamp,
// where contentstamp is provided by the view.
$componentid = $dataformid . "_{$viewid}";
$cachedfilepath = dataform_rss_get_cached_file_path($componentid);
$contentstamp = $cachedfilepath ? dataform_rss_get_cached_content_stamp($cachedfilepath) : null;
$newcontentstamp = $view->get_content_stamp();
$hasnewcontent = $newcontentstamp !== $contentstamp;
// Neither existing nor new.
if (!$cachedfilepath and !$hasnewcontent) {
return null;
}
if ($cachedfilepath) {
// Use cache under 60 seconds.
$cachetime = filemtime($cachedfilepath);
if (time() - $cachetime < 60) {
return $cachedfilepath;
}
// Use cache if there is nothing new.
if (!$hasnewcontent) {
return $cachedfilepath;
}
// Cached file is outdated so delete it.
$instance = (object) array('id' => $componentid);
rss_delete_file('mod_dataform', $instance);
}
// Still here, fetch new content.
// Each article is an stdclass {title, descrition, pubdate, entrylink}.
if (!($items = $view->get_rss_items())) {
return null;
}
// First all rss feeds common headers.
$headertitle = $view->get_rss_header_title();
$headerlink = $view->get_rss_header_link();
$headerdescription = $view->get_rss_header_description();
$header = rss_standard_header($headertitle, $headerlink, $headerdescription);
if (empty($header)) {
return null;
}
// Now all rss feeds common footers.
$footer = rss_standard_footer();
if (empty($footer)) {
return null;
}
// All's good, save the content to file.
$articles = rss_add_items($items);
$rss = $header . $articles . $footer;
$filename = $componentid . "_{$newcontentstamp}";
$status = rss_save_file('mod_dataform', $filename, $rss);
$dirpath = dataform_rss_get_cache_dir_path();
return "{$dirpath}/{$filename}.xml";
}
/**
* Given a forum object, deletes all cached RSS files associated with it.
*
* @param stdClass $forum
*/
function forum_rss_delete_file($forum) {
rss_delete_file('mod_forum', $forum);
}
/**
* Given a anonforum object, deletes all cached RSS files associated with it.
*
* @param stdClass $anonforum
*/
function anonforum_rss_delete_file($anonforum)
{
rss_delete_file('mod_anonforum', $anonforum);
}
/**
* Given a twf object, deletes all cached RSS files associated with it.
*
* @param stdClass $twf
*/
function twf_rss_delete_file($twf)
{
rss_delete_file('mod_twf', $twf);
}
/**
* Given a quora object, deletes all cached RSS files associated with it.
*
* @param stdClass $quora
*/
function quora_rss_delete_file($quora)
{
rss_delete_file('mod_quora', $quora);
}
/**
* Given a glossary object, deletes all cached RSS files associated with it.
*
* @param stdClass $glossary
*/
function glossary_rss_delete_file($glossary)
{
global $CFG;
require_once "{$CFG->libdir}/rsslib.php";
rss_delete_file('mod_glossary', $glossary);
}
/**
* Given a database object, deletes all cached RSS files associated with it.
*
* @param stdClass $data
*/
function data_rss_delete_file($data)
{
global $CFG;
require_once "{$CFG->libdir}/rsslib.php";
rss_delete_file('mod_data', $data);
}