Introduce includes/utils directory

[lhc/web/wiklou.git] / includes / Revision.php

diff --git a/includes/Revision.php b/includes/Revision.php
index 2bdc7c0..4446173 100644 (file)
--- a/includes/Revision.php
+++ b/includes/Revision.php
@@ -61,6 +61,11 @@ class Revision implements IDBAccessObject {
         */
        protected $mContentHandler;
 
+       /**
+        * @var int
+        */
+       protected $mQueryFlags = 0;
+
        // Revision deletion constants
        const DELETED_TEXT = 1;
        const DELETED_COMMENT = 2;
@@ -111,11 +116,13 @@ class Revision implements IDBAccessObject {
                if ( $id ) {
                        // Use the specified ID
                        $conds['rev_id'] = $id;
+                       return self::newFromConds( $conds, (int)$flags );
                } else {
                        // Use a join to get the latest revision
                        $conds[] = 'rev_id=page_latest';
+                       $db = wfGetDB( ( $flags & self::READ_LATEST ) ? DB_MASTER : DB_SLAVE );
+                       return self::loadFromConds( $db, $conds, $flags );
                }
-               return self::newFromConds( $conds, (int)$flags );
        }
 
        /**
@@ -298,6 +305,9 @@ class Revision implements IDBAccessObject {
                                $rev = self::loadFromConds( $dbw, $conditions, $flags );
                        }
                }
+               if ( $rev ) {
+                       $rev->mQueryFlags = $flags;
+               }
                return $rev;
        }
 
@@ -423,6 +433,36 @@ class Revision implements IDBAccessObject {
                return $fields;
        }
 
+       /**
+        * Return the list of revision fields that should be selected to create
+        * a new revision from an archive row.
+        * @return array
+        */
+       public static function selectArchiveFields() {
+               global $wgContentHandlerUseDB;
+               $fields = array(
+                       'ar_id',
+                       'ar_page_id',
+                       'ar_rev_id',
+                       'ar_text_id',
+                       'ar_timestamp',
+                       'ar_comment',
+                       'ar_user_text',
+                       'ar_user',
+                       'ar_minor_edit',
+                       'ar_deleted',
+                       'ar_len',
+                       'ar_parent_id',
+                       'ar_sha1',
+               );
+
+               if ( $wgContentHandlerUseDB ) {
+                       $fields[] = 'ar_content_format';
+                       $fields[] = 'ar_content_model';
+               }
+               return $fields;
+       }
+
        /**
         * Return the list of text fields that should be selected to read the
         * revision text
@@ -1209,35 +1249,7 @@ class Revision implements IDBAccessObject {
 
                // If the text was fetched without an error, convert it
                if ( $text !== false ) {
-                       if ( in_array( 'gzip', $flags ) ) {
-                               # Deal with optional compression of archived pages.
-                               # This can be done periodically via maintenance/compressOld.php, and
-                               # as pages are saved if $wgCompressRevisions is set.
-                               $text = gzinflate( $text );
-                       }
-
-                       if ( in_array( 'object', $flags ) ) {
-                               # Generic compressed storage
-                               $obj = unserialize( $text );
-                               if ( !is_object( $obj ) ) {
-                                       // Invalid object
-                                       wfProfileOut( __METHOD__ );
-                                       return false;
-                               }
-                               $text = $obj->getText();
-                       }
-
-                       global $wgLegacyEncoding;
-                       if ( $text !== false && $wgLegacyEncoding
-                               && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags ) )
-                       {
-                               # Old revisions kept around in a legacy encoding?
-                               # Upconvert on demand.
-                               # ("utf8" checked for compatibility with some broken
-                               #  conversion scripts 2008-12-30)
-                               global $wgContLang;
-                               $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
-                       }
+                       $text = self::decompressRevisionText( $text, $flags );
                }
                wfProfileOut( __METHOD__ );
                return $text;
@@ -1272,6 +1284,46 @@ class Revision implements IDBAccessObject {
                return implode( ',', $flags );
        }
 
+       /**
+        * Re-converts revision text according to it's flags.
+        *
+        * @param $text Mixed: reference to a text
+        * @param $flags array: compression flags
+        * @return String|bool decompressed text, or false on failure
+        */
+       public static function decompressRevisionText( $text, $flags ) {
+               if ( in_array( 'gzip', $flags ) ) {
+                       # Deal with optional compression of archived pages.
+                       # This can be done periodically via maintenance/compressOld.php, and
+                       # as pages are saved if $wgCompressRevisions is set.
+                       $text = gzinflate( $text );
+               }
+
+               if ( in_array( 'object', $flags ) ) {
+                       # Generic compressed storage
+                       $obj = unserialize( $text );
+                       if ( !is_object( $obj ) ) {
+                               // Invalid object
+                               return false;
+                       }
+                       $text = $obj->getText();
+               }
+
+               global $wgLegacyEncoding;
+               if ( $text !== false && $wgLegacyEncoding
+                       && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags ) )
+               {
+                       # Old revisions kept around in a legacy encoding?
+                       # Upconvert on demand.
+                       # ("utf8" checked for compatibility with some broken
+                       #  conversion scripts 2008-12-30)
+                       global $wgContLang;
+                       $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
+               }
+
+               return $text;
+       }
+
        /**
         * Insert a new revision into the database, returning the new revision ID
         * number on success and dies horribly on failure.
@@ -1465,20 +1517,30 @@ class Revision implements IDBAccessObject {
                        $dbr = wfGetDB( DB_SLAVE );
                        $row = $dbr->selectRow( 'text',
                                array( 'old_text', 'old_flags' ),
-                               array( 'old_id' => $this->getTextId() ),
+                               array( 'old_id' => $textId ),
                                __METHOD__ );
                }
 
-               if ( !$row && wfGetLB()->getServerCount() > 1 ) {
-                       // Possible slave lag!
+               // Fallback to the master in case of slave lag. Also use FOR UPDATE if it was
+               // used to fetch this revision to avoid missing the row due to REPEATABLE-READ.
+               $forUpdate = ( $this->mQueryFlags & self::READ_LOCKING == self::READ_LOCKING );
+               if ( !$row && ( $forUpdate || wfGetLB()->getServerCount() > 1 ) ) {
                        $dbw = wfGetDB( DB_MASTER );
                        $row = $dbw->selectRow( 'text',
                                array( 'old_text', 'old_flags' ),
-                               array( 'old_id' => $this->getTextId() ),
-                               __METHOD__ );
+                               array( 'old_id' => $textId ),
+                               __METHOD__,
+                               $forUpdate ? array( 'FOR UPDATE' ) : array() );
+               }
+
+               if ( !$row ) {
+                       wfDebugLog( 'Revision', "No text row with ID '$textId' (revision {$this->getId()})." );
                }
 
                $text = self::getRevisionText( $row );
+               if ( $row && $text === false ) {
+                       wfDebugLog( 'Revision', "No blob for text row '$textId' (revision {$this->getId()})." );
+               }
 
                # No negative caching -- negative hits on text rows may be due to corrupted slave servers
                if ( $wgRevisionCacheExpiry && $text !== false ) {