SERVER-30353 Create an index observer to notify us of changes made to index and document keys

1 files changed, 26 insertions, 0 deletions

diff --git a/src/mongo/db/catalog/collection_impl.h b/src/mongo/db/catalog/collection_impl.h
index 4a766faa9aa..1fdfc40d1fa 100644
--- a/src/mongo/db/catalog/collection_impl.h
+++ b/src/mongo/db/catalog/collection_impl.h
@@ -30,8 +30,12 @@
 
 #include "mongo/db/catalog/collection.h"
 #include "mongo/db/catalog/collection_catalog_entry.h"
+#include "mongo/db/catalog/index_catalog.h"
+#include "mongo/db/concurrency/d_concurrency.h"
 
 namespace mongo {
+class IndexConsistency;
+class IndexObserver;
 class UUIDCatalog;
 class CollectionImpl final : virtual public Collection::Impl,
                              virtual CappedCallback,
@@ -349,6 +353,15 @@ public:
      */
     const CollatorInterface* getDefaultCollator() const final;
 
+    /**
+     * Calls the Inform function in the IndexObserver if it's hooked.
+     */
+    void informIndexObserver(OperationContext* opCtx,
+                             const IndexDescriptor* descriptor,
+                             const IndexKeyEntry& indexEntry,
+                             const ValidationOperation operation) const;
+
+
 private:
     inline DatabaseCatalogEntry* dbce() const final {
         return this->_dbce;
@@ -359,6 +372,16 @@ private:
     }
 
     /**
+     * Hooks the IndexObserver into the collection.
+     */
+    void hookIndexObserver(IndexConsistency* consistency);
+
+    /**
+     * Unhooks the IndexObserver from the collection.
+     */
+    void unhookIndexObserver();
+
+    /**
      * Returns a non-ok Status if document does not pass this collection's validator.
      */
     Status checkValidation(OperationContext* opCtx, const BSONObj& document) const;
@@ -406,6 +429,9 @@ private:
     CollectionInfoCache _infoCache;
     IndexCatalog _indexCatalog;
 
+    mutable stdx::mutex _indexObserverMutex;
+    mutable std::unique_ptr<IndexObserver> _indexObserver;
+
     // The default collation which is applied to operations and indices which have no collation of
     // their own. The collection's validator will respect this collation.
     //