Conversion from 1.4 schema, zero downtime

diff --git a/includes/Image.php b/includes/Image.php
index 0b5ac62..5824da8 100644 (file)
--- a/includes/Image.php
+++ b/includes/Image.php
@@ -237,6 +237,10 @@ class Image
                        $this->fileExists = true;
                        $this->loadFromRow( $row );
                        $this->imagePath = $this->getFullPath();
+                       // Check for rows from a previous schema, quietly upgrade them
+                       if ( $this->type == -1 ) {
+                               $this->upgradeRow();
+                       }
                } elseif ( $wgUseSharedUploads && $wgSharedUploadDBname ) {
                        # In case we're on a wgCapitalLinks=false wiki, we 
                        # capitalize the first letter of the filename before 
@@ -252,6 +256,11 @@ class Image
                                $this->imagePath = $this->getFullPath(true);
                                $this->name = $name;
                                $this->loadFromRow( $row );
+                               
+                               // Check for rows from a previous schema, quietly upgrade them
+                               if ( $this->type == -1 ) {
+                                       $this->upgradeRow();
+                               }
                        }
                }
                
@@ -299,6 +308,38 @@ class Image
                }
        }
 
+       /** 
+        * Metadata was loaded from the database, but the row had a marker indicating it needs to be 
+        * upgraded from the 1.4 schema, which had no width, height, bits or type. Upgrade the row.
+        */
+       function upgradeRow() {
+               global $wgDBname, $wgSharedUploadDBname;
+               $fname = 'Image::upgradeRow';
+               $this->loadFromFile();
+               $dbw =& wfGetDB( DB_MASTER );
+
+               if ( $this->fromSharedDirectory ) {
+                       if ( !$wgSharedUploadDBname ) {
+                               return;
+                       }
+
+                       // Write to the other DB using selectDB, not database selectors
+                       // This avoids breaking replication in MySQL
+                       $dbw->selectDB( $wgSharedUploadDBname );
+               }
+               $dbw->update( '`image`', 
+                       array( 
+                               'img_width' => $this->width,
+                               'img_height' => $this->height,
+                               'img_bits' => $this->bits,
+                               'img_type' => $this->type,
+                       ), array( 'img_name' => $this->name ), $fname
+               );
+               if ( $this->fromSharedDirectory ) {
+                       $dbw->selectDB( $wgDBname );
+               }
+       }
+                               
        /**
         * Return the name of this image
         * @access public

diff --git a/maintenance/archives/patch-img_width.sql b/maintenance/archives/patch-img_width.sql
index 5531259..9dc233f 100644 (file)
--- a/maintenance/archives/patch-img_width.sql
+++ b/maintenance/archives/patch-img_width.sql
@@ -1,10 +1,10 @@
 -- Extra image metadata, added for 1.5
 
 ALTER TABLE /*$wgDBprefix*/image ADD (
-  img_width int(5) NOT NULL default '0',
-  img_height int(5) NOT NULL default '0',
-  img_bits int(5) NOT NULL default '0',
-  img_type int(5) NOT NULL default '0'
+  img_width int(5) NOT NULL default 0,
+  img_height int(5) NOT NULL default 0,
+  img_bits int(5) NOT NULL default 0,
+  img_type int(5) NOT NULL default -1
 );
 
 ALTER TABLE /*$wgDBprefix*/oldimage ADD (