SERVER-13951: Add rollback of collection metadata

This implements rollback of collection creation or dropping, including
associated indexes.

2 files changed, 23 insertions, 6 deletions

diff --git a/src/mongo/db/catalog/database.cpp b/src/mongo/db/catalog/database.cpp
index 2fcabd06962..83ba92727c0 100644
--- a/src/mongo/db/catalog/database.cpp
+++ b/src/mongo/db/catalog/database.cpp
@@ -53,7 +53,7 @@
 #include "mongo/db/server_parameters.h"
 #include "mongo/db/storage_options.h"
 #include "mongo/db/storage/storage_engine.h"
-#include "mongo/db/catalog/collection.h"
+#include "mongo/db/storage/recovery_unit.h"
 #include "mongo/util/log.h"
 
 namespace mongo {
@@ -67,6 +67,18 @@ namespace mongo {
                  NamespaceString::normal( ns ) );
     }
 
+    class Database::CollectionCacheChange : public RecoveryUnit::Change {
+    public:
+        CollectionCacheChange(Database* db, const StringData& ns)
+        : _db(db), _ns(ns.toString()) { }
+
+        void rollback() { _db->_clearCollectionCache(_ns); }
+        void commit() { }
+    private:
+        Database* const _db;
+        std::string _ns;
+    };
+
     Database::~Database() {
         for (CollectionMap::const_iterator i = _collections.begin(); i != _collections.end(); ++i)
             delete i->second;
@@ -299,6 +311,8 @@ namespace mongo {
             return Status::OK();
         }
 
+        txn->recoveryUnit()->registerChange( new CollectionCacheChange(this, fullns) );
+
         {
             NamespaceString s( fullns );
             verify( s.db() == _name );
@@ -470,13 +484,14 @@ namespace mongo {
 
         audit::logCreateCollection( currentClient.get(), ns );
 
-        Status status = _dbEntry->createCollection( txn, ns,
-                                                    options, allocateDefaultSpace );
-        massertStatusOK( status );
+        txn->recoveryUnit()->registerChange( new CollectionCacheChange(this, ns) );
 
+        Status status = _dbEntry->createCollection(txn, ns,
+                                                options, allocateDefaultSpace);
+        massertStatusOK(status);
 
-        Collection* collection = getCollection( txn, ns );
-        invariant( collection );
+        Collection* collection = getCollection(txn, ns);
+        invariant(collection);
 
         if ( createIdIndex ) {
             if ( collection->requiresIdIndex() ) {
diff --git a/src/mongo/db/catalog/database.h b/src/mongo/db/catalog/database.h
index 3180694e111..c13a12bbdbe 100644
--- a/src/mongo/db/catalog/database.h
+++ b/src/mongo/db/catalog/database.h
@@ -142,6 +142,8 @@ namespace mongo {
 
         void _clearCollectionCache_inlock( const StringData& fullns );
 
+        class CollectionCacheChange; // to allow rollback actions for invalidating above cache
+
         const std::string _name; // "alleyinsider"
 
         boost::scoped_ptr<DatabaseCatalogEntry> _dbEntry;