Bug #14724: Incremental update of Bazaar history broken by instability in revision numbers

Author: Knut Anders Hatlen

src/org/opensolaris/opengrok/history/FileHistoryCache.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -292,6 +292,13 @@ public String getLatestCachedRevision(Repository repository) {
         return null;
     }
 
+    @Override
+    public void clear(Repository repository) {
+        // We only expect this method to be called if the cache supports
+        // incremental update, so it's not implemented here for now.
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public String getInfo() {
         return getClass().getSimpleName();

src/org/opensolaris/opengrok/history/HistoryCache.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 package org.opensolaris.opengrok.history;
@@ -105,6 +105,14 @@ boolean hasCacheForDirectory(File directory, Repository repository)
     String getLatestCachedRevision(Repository repository)
             throws HistoryException;
 
+    /**
+     * Clear the history cache for a repository.
+     *
+     * @param repository the repository whose cache to clear
+     * @throws HistoryException if the cache couldn't be cleared
+     */
+    void clear(Repository repository) throws HistoryException;
+
     /**
      * Get a string with information about the history cache.
      *

src/org/opensolaris/opengrok/history/JDBCHistoryCache.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -1125,6 +1125,46 @@ private String getLatestRevisionForRepository(Repository repository)
         }
     }
 
+    @Override
+    public void clear(Repository repository) throws HistoryException {
+        try {
+            for (int i = 0;; i++) {
+                try {
+                    clearHistoryForRepository(repository);
+                    return;
+                } catch (SQLException sqle) {
+                    handleSQLException(sqle, i);
+                }
+            }
+        } catch (SQLException sqle) {
+            throw new HistoryException(sqle);
+        }
+    }
+
+    /**
+     * Helper for {@link #clear(Repository)}.
+     */
+    private void clearHistoryForRepository(Repository repository)
+            throws SQLException {
+        final ConnectionResource conn =
+                connectionManager.getConnectionResource();
+        try {
+            // This statement shouldn't be called very frequently, so don't
+            // care about caching it...
+            PreparedStatement ps = conn.prepareStatement(
+                    getQuery("clearRepository"));
+            try {
+                ps.setInt(1, getRepositoryId(conn, repository));
+                ps.execute();
+                conn.commit();
+            } finally {
+                ps.close();
+            }
+        } finally {
+            connectionManager.releaseConnection(conn);
+        }
+    }
+
     @Override
     public String getInfo() throws HistoryException {
         return info;

src/org/opensolaris/opengrok/history/JDBCHistoryCache_queries.properties

@@ -18,7 +18,7 @@
 #
 
 #
-# Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
+# Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
 
@@ -168,3 +168,7 @@ getMaxDirId=SELECT MAX(ID) FROM OPENGROK.DIRECTORIES
 getMaxChangesetId=SELECT MAX(ID) FROM OPENGROK.CHANGESETS
 
 getMaxAuthorId=SELECT MAX(ID) FROM OPENGROK.AUTHORS
+
+# Cascading deletes will take care of deleting all data associated with the
+# repository from the other tables.
+clearRepository=DELETE FROM OPENGROK.REPOSITORIES WHERE ID=?

src/org/opensolaris/opengrok/history/Repository.java

@@ -194,7 +194,33 @@ final void createCache(HistoryCache cache, String sinceRevision)
         }
 
         File directory = new File(getDirectoryName());
-        History history = getHistory(directory, sinceRevision);
+
+        History history;
+        try {
+            history = getHistory(directory, sinceRevision);
+        } catch (HistoryException he) {
+            if (sinceRevision == null) {
+                // Failed to get full history, so fail.
+                throw he;
+            } else {
+                // Failed to get partial history. This may have been caused
+                // by changes in the revision numbers since the last update
+                // (bug #14724) so we'll try to regenerate the cache from
+                // scratch instead.
+                OpenGrokLogger.getLogger().log(Level.INFO,
+                        "Failed to get partial history. Attempting to " +
+                        "recreate the history cache from scratch.", he);
+                history = null;
+            }
+        }
+
+        if (sinceRevision != null && history == null) {
+            // Failed to get partial history, now get full history instead.
+            history = getHistory(directory);
+            // Got full history successfully. Clear the history cache so that
+            // we can recreate it from scratch.
+            cache.clear(this);
+        }
 
         if (history != null) {
             cache.store(history, this);

test/org/opensolaris/opengrok/history/JDBCHistoryCacheTest.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -230,6 +230,15 @@ public void testStoreAndGet() throws Exception {
                 updatedHistory.getHistoryEntries());
         assertSameEntry(newEntry, updatedEntries.removeFirst());
         assertSameEntries(historyToStore.getHistoryEntries(), updatedEntries);
+
+        // test clearing of cache
+        cache.clear(repos);
+        History clearedHistory = cache.get(reposRoot, repos, true);
+        assertTrue("History should be empty",
+                clearedHistory.getHistoryEntries().isEmpty());
+        cache.store(historyToStore, repos);
+        assertSameEntries(historyToStore.getHistoryEntries(),
+                cache.get(reposRoot, repos, true).getHistoryEntries());
     }
 
     /**