<?php
/**
- *
- *
+ * @defgroup ExternalStorage ExternalStorage
+ */
+
+/**
* Constructor class for data kept in external repositories
*
* External repositories might be populated by maintenance/async
* scripts, thus partial moving of data may be possible, as well
* as possibility to have any storage format (i.e. for archives)
*
+ * @ingroup ExternalStorage
*/
-
class ExternalStore {
- /* Fetch data from given URL */
- function fetchFromURL($url) {
+ var $mParams;
+
+ function __construct( $params = array() ) {
+ $this->mParams = $params;
+ }
+
+ /**
+ * Fetch data from given URL
+ *
+ * @param $url String: The URL of the text to get
+ * @param $params Array: associative array of parameters for the ExternalStore object.
+ * @return The text stored or false on error
+ */
+ static function fetchFromURL( $url, $params = array() ) {
global $wgExternalStores;
- if (!$wgExternalStores)
+ if( !$wgExternalStores )
return false;
- @list($proto,$path)=explode('://',$url,2);
- /* Bad URL */
- if ($path=="")
+ $parts = explode( '://', $url, 2 );
+
+ if ( count( $parts ) != 2 ) {
return false;
+ }
+
+ list( $proto, $path ) = $parts;
- $store =& ExternalStore::getStoreObject( $proto );
+ if ( $path == '' ) { // Bad URL
+ return false;
+ }
+
+ $store = self::getStoreObject( $proto, $params );
if ( $store === false )
return false;
- return $store->fetchFromURL($url);
+ return $store->fetchFromURL( $url );
}
/**
- * Get an external store object of the given type
+ * Get an external store object of the given type, with the given parameters
+ *
+ * @param $proto String: type of external storage, should be a value in $wgExternalStores
+ * @param $params Array: associative array of parameters for the ExternalStore object.
+ * @return ExternalStore subclass or false on error
*/
- function &getStoreObject( $proto ) {
+ static function getStoreObject( $proto, $params = array() ) {
global $wgExternalStores;
- if (!$wgExternalStores)
+ if( !$wgExternalStores )
return false;
/* Protocol not enabled */
- if (!in_array( $proto, $wgExternalStores ))
+ if( !in_array( $proto, $wgExternalStores ) )
return false;
- $class='ExternalStore'.ucfirst($proto);
+ $class = 'ExternalStore' . ucfirst( $proto );
/* Any custom modules should be added to $wgAutoLoadClasses for on-demand loading */
- if (!class_exists($class)) {
+ if( !class_exists( $class ) ) {
return false;
}
- $store=new $class();
- return $store;
+
+ return new $class($params);
}
/**
* Store a data item to an external store, identified by a partial URL
* The protocol part is used to identify the class, the rest is passed to the
* class itself as a parameter.
- * Returns the URL of the stored data item, or false on error
+ * @return The URL of the stored data item, or false on error
*/
- function insert( $url, $data ) {
+ static function insert( $url, $data, $params = array() ) {
list( $proto, $params ) = explode( '://', $url, 2 );
- $store =& ExternalStore::getStoreObject( $proto );
+ $store = self::getStoreObject( $proto, $params );
if ( $store === false ) {
return false;
} else {
return $store->store( $params, $data );
}
}
+
+ /**
+ * Like insert() above, but does more of the work for us.
+ * This function does not need a url param, it builds it by
+ * itself. It also fails-over to the next possible clusters.
+ *
+ * @param $data String
+ * @param $storageParams Array: associative array of parameters for the ExternalStore object.
+ * @return The URL of the stored data item, or false on error
+ */
+ public static function insertToDefault( $data, $storageParams = array() ) {
+ global $wgDefaultExternalStore;
+ $tryStores = (array)$wgDefaultExternalStore;
+ $error = false;
+ while ( count( $tryStores ) > 0 ) {
+ $index = mt_rand(0, count( $tryStores ) - 1);
+ $storeUrl = $tryStores[$index];
+ wfDebug( __METHOD__.": trying $storeUrl\n" );
+ list( $proto, $params ) = explode( '://', $storeUrl, 2 );
+ $store = self::getStoreObject( $proto, $storageParams );
+ if ( $store === false ) {
+ throw new MWException( "Invalid external storage protocol - $storeUrl" );
+ }
+ try {
+ $url = $store->store( $params, $data ); // Try to save the object
+ } catch ( DBConnectionError $error ) {
+ $url = false;
+ } catch( DBQueryError $error ) {
+ $url = false;
+ }
+ if ( $url ) {
+ return $url; // Done!
+ } else {
+ unset( $tryStores[$index] ); // Don't try this one again!
+ $tryStores = array_values( $tryStores ); // Must have consecutive keys
+ wfDebugLog( 'ExternalStorage', "Unable to store text to external storage $storeUrl" );
+ }
+ }
+ // All stores failed
+ if ( $error ) {
+ // Rethrow the last connection error
+ throw $error;
+ } else {
+ throw new MWException( "Unable to store text to external storage" );
+ }
+ }
+
+ /** Like insertToDefault, but inserts on another wiki */
+ public static function insertToForeignDefault( $data, $wiki ) {
+ return self::insertToDefault( $data, array( 'wiki' => $wiki ) );
+ }
}
-?>