Fix for missing end tag </page> on some exports

T203424 replaced streaming mode with batched queries.
However, it did not properly handle some values of
the $wgExportMaxHistory config variable, and emitted
broken XML. This change fixes that issue.

Bug: T207974
Change-Id: Iade3fc603e513da51b7a970c16275516c02ede49

diff --git a/includes/export/WikiExporter.php b/includes/export/WikiExporter.php
index 32f7519..e6b9719 100644 (file)
--- a/includes/export/WikiExporter.php
+++ b/includes/export/WikiExporter.php
@@ -418,7 +418,7 @@ class WikiExporter {
                        $queryConds[] = 'rev_page>' . intval( $revPage ) . ' OR (rev_page=' .
                                intval( $revPage ) . ' AND rev_id' . $op . intval( $revId ) . ')';
 
-                       # Do the query!
+                       # Do the query and process any results, remembering max ids for the next iteration.
                        $result = $this->db->select(
                                $tables,
                                $fields,
@@ -427,15 +427,18 @@ class WikiExporter {
                                $opts,
                                $join
                        );
-                       # Output dump results, get new max ids.
-                       $lastRow = $this->outputPageStream( $result, $lastRow );
-
-                       if ( !$result->numRows() || !$lastRow ) {
-                               $done = true;
-                       } else {
+                       if ( $result->numRows() > 0 ) {
+                               $lastRow = $this->outputPageStreamBatch( $result, $lastRow );
                                $rowCount += $result->numRows();
                                $revPage = $lastRow->rev_page;
                                $revId = $lastRow->rev_id;
+                       } else {
+                               $done = true;
+                       }
+
+                       // If we are finished, close off final page element (if any).
+                       if ( $done && $lastRow ) {
+                               $this->finishPageStreamOutput( $lastRow );
                        }
                }
        }
@@ -445,46 +448,49 @@ class WikiExporter {
         * The result set should be sorted/grouped by page to avoid duplicate
         * page records in the output.
         *
-        * @param ResultWrapper $resultset
+        * @param ResultWrapper $results
         * @param object $lastRow the last row output from the previous call (or null if none)
         * @return object the last row processed
         */
-       protected function outputPageStream( $resultset, $lastRow ) {
-               if ( $resultset->numRows() ) {
-                       foreach ( $resultset as $row ) {
-                               if ( $lastRow === null ||
-                                       $lastRow->page_namespace != $row->page_namespace ||
-                                       $lastRow->page_title != $row->page_title ) {
-                                       if ( $lastRow !== null ) {
-                                               $output = '';
-                                               if ( $this->dumpUploads ) {
-                                                       $output .= $this->writer->writeUploads( $lastRow, $this->dumpUploadFileContents );
-                                               }
-                                               $output .= $this->writer->closePage();
-                                               $this->sink->writeClosePage( $output );
+       protected function outputPageStreamBatch( $results, $lastRow ) {
+               foreach ( $results as $row ) {
+                       if ( $lastRow === null ||
+                               $lastRow->page_namespace != $row->page_namespace ||
+                               $lastRow->page_title != $row->page_title ) {
+                               if ( $lastRow !== null ) {
+                                       $output = '';
+                                       if ( $this->dumpUploads ) {
+                                               $output .= $this->writer->writeUploads( $lastRow, $this->dumpUploadFileContents );
                                        }
-                                       $output = $this->writer->openPage( $row );
-                                       $this->sink->writeOpenPage( $row, $output );
+                                       $output .= $this->writer->closePage();
+                                       $this->sink->writeClosePage( $output );
                                }
-                               $output = $this->writer->writeRevision( $row );
-                               $this->sink->writeRevision( $row, $output );
-                               $lastRow = $row;
+                               $output = $this->writer->openPage( $row );
+                               $this->sink->writeOpenPage( $row, $output );
                        }
-               } elseif ( $lastRow !== null ) {
-                       // Empty resultset means done with all batches  Close off final page element (if any).
-                       $output = '';
-                       if ( $this->dumpUploads ) {
-                               $output .= $this->writer->writeUploads( $lastRow, $this->dumpUploadFileContents );
-                       }
-                       $output .= $this->author_list;
-                       $output .= $this->writer->closePage();
-                       $this->sink->writeClosePage( $output );
-                       $lastRow = null;
+                       $output = $this->writer->writeRevision( $row );
+                       $this->sink->writeRevision( $row, $output );
+                       $lastRow = $row;
                }
 
                return $lastRow;
        }
 
+       /**
+        * Final page stream output, after all batches are complete
+        *
+        * @param object $lastRow the last row output from the last batch (or null if none)
+        */
+       protected function finishPageStreamOutput( $lastRow ) {
+               $output = '';
+               if ( $this->dumpUploads ) {
+                       $output .= $this->writer->writeUploads( $lastRow, $this->dumpUploadFileContents );
+               }
+               $output .= $this->author_list;
+               $output .= $this->writer->closePage();
+               $this->sink->writeClosePage( $output );
+       }
+
        /**
         * @param ResultWrapper $resultset
         * @return int the log_id value of the last item output, or null if none