/**
* Function to get the contents of the URL. It will get the contents using Gzip compression if possible in
* order to save bandwidth. It uses the HTTP Client class from Simon Willison to do the dirty work.
*
* More information about the HTTP client class can be found on: http://scripts.incutio.com/httpclient/
*
* If it fails to retrieve the data, it will raise a fatal error.
*
* By default, it will cache the downloaded data based on the etag and last-modified headers. The cache files
* are stored in the temp directory of the Yellow Duck framework and have the extension "wch". You can delete
* these automatically as they will be recreated on the fly if needed.
*
* For configuring the cache, there are two configuration variables you can redefine if needed:
* YD_HTTP_CACHE_TIMEOUT: the lifetime of the cache in seconds (default: 3600).
* YD_HTTP_CACHE_USEHEAD: if a HEAD HTTP request should be used to verify the cache validity (default: 1).
*
* @param $cache (optional) Indicate if the web content should be cached or not. By default, caching is
* turned on.
* @param $fail (optional) Whether to fail or not if the contents cannot be downloaded. Defaults to true.
*
* @returns Returns the contents of the URL.
*/
function getContents($cache = true, $fail = true)
{
// Check if caching is enabled
$cacheFName = null;
// Check the cache
if ($cache == true) {
// Include the filesystem library
include_once YD_DIR_HOME_CLS . '/YDFileSystem.php';
// Check if we need to use the HTTP HEAD function
if (YDConfig::get('YD_HTTP_CACHE_USEHEAD') == 1) {
// Get the headers
$headers = $this->getHeaders();
// Check if we have etag or last modified
if (isset($headers['etag']) || isset($headers['last-modified'])) {
$cacheFName = $this->getUrl();
if (isset($headers['etag'])) {
$cacheFName .= $headers['etag'];
}
if (isset($headers['last-modified'])) {
$cacheFName .= $headers['last-modified'];
}
if (isset($headers['content-length'])) {
$cacheFName .= $headers['content-length'];
}
$cacheFName = YD_TMP_PRE . 'W_' . md5($cacheFName) . '.wch';
$cacheFName = YD_DIR_TEMP . '/' . $cacheFName;
}
}
// If the cache filename is null, use the default one
if ($cacheFName == null) {
$cacheFName = YD_DIR_TEMP . '/' . YD_TMP_PRE . 'W_' . md5($this->getUrl()) . '.wch';
}
// Use the cache file if any
if (is_file($cacheFName)) {
$file = new YDFSFile($cacheFName);
$cacheValidTime = $file->getLastModified() + YDConfig::get('YD_HTTP_CACHE_TIMEOUT');
if (time() < $cacheValidTime) {
return $file->getContents();
}
}
}
// Create a new HTTP client
$client = $this->_getHttpClient();
// Now send the request
$result = @$client->doRequest();
// Check if there was a result
if ($result == false) {
if ($fail) {
trigger_error('Failed to retrieve the data from the url "' . $this->getUrl() . '". ' . $client->getError(), YD_ERROR);
} else {
return false;
}
} else {
$data = @$client->getContent();
}
// Check if caching is enabled
if ($cache == true) {
// Save the cached data
if ($cacheFName != null) {
$dir = new YDFSDirectory(YD_DIR_TEMP);
$dir->createFile($cacheFName, $data);
}
}
// Return the data
return $data;
}
