SERVER-29276 adds functions to DropPendingCollectionReaper for rollback

1 files changed, 65 insertions, 0 deletions

diff --git a/src/mongo/db/repl/drop_pending_collection_reaper.cpp b/src/mongo/db/repl/drop_pending_collection_reaper.cpp
index d2aec5aaaae..63da089f28c 100644
--- a/src/mongo/db/repl/drop_pending_collection_reaper.cpp
+++ b/src/mongo/db/repl/drop_pending_collection_reaper.cpp
@@ -97,6 +97,71 @@ boost::optional<OpTime> DropPendingCollectionReaper::getEarliestDropOpTime() {
     return it->first;
 }
 
+bool DropPendingCollectionReaper::dropCollectionAtOpTime(OperationContext* opCtx,
+                                                         const OpTime& opTime) {
+    // Every node cleans up its own drop-pending collections. We should never replicate these drops
+    // because these are internal operations.
+    UnreplicatedWritesBlock uwb(opCtx);
+
+    NamespaceString pendingNss;
+    {
+        stdx::lock_guard<stdx::mutex> lock(_mutex);
+        auto pendingNssIt = _dropPendingNamespaces.find(opTime);
+        if (pendingNssIt == _dropPendingNamespaces.end()) {
+            warning() << "Cannot find drop-pending namespace at OpTime " << opTime << " to drop.";
+            return false;
+        }
+
+        pendingNss = pendingNssIt->second;
+        _dropPendingNamespaces.erase(opTime);
+    }
+
+    log() << "Completing collection drop for " << pendingNss << " with drop OpTime " << opTime;
+
+    auto status = _storageInterface->dropCollection(opCtx, pendingNss);
+    if (!status.isOK()) {
+        warning() << "Failed to remove drop-pending collection " << pendingNss
+                  << " with drop OpTime " << opTime << ": " << status;
+    }
+
+    return true;
+}
+
+bool DropPendingCollectionReaper::rollBackDropPendingCollection(OperationContext* opCtx,
+                                                                const OpTime& opTime,
+                                                                StringData collName) {
+    // Every node cleans up its own drop-pending collections. We should never replicate these
+    // renames because these are internal operations.
+    UnreplicatedWritesBlock uwb(opCtx);
+
+    NamespaceString pendingNss;
+    {
+        stdx::lock_guard<stdx::mutex> lock(_mutex);
+        auto pendingNssIt = _dropPendingNamespaces.find(opTime);
+        if (pendingNssIt == _dropPendingNamespaces.end()) {
+            warning() << "Cannot find drop-pending namespace at OpTime " << opTime
+                      << " for collection " << collName << " to roll back.";
+            return false;
+        }
+
+        pendingNss = pendingNssIt->second;
+        _dropPendingNamespaces.erase(opTime);
+    }
+
+    NamespaceString newNss(pendingNss.db(), collName);
+    log() << "Rolling back collection drop for " << pendingNss << " with drop OpTime " << opTime
+          << " to namespace " << newNss;
+
+    auto status = _storageInterface->renameCollection(opCtx, pendingNss, newNss, true);
+    if (!status.isOK()) {
+        warning() << "Failed to roll back drop-pending collection " << pendingNss
+                  << " with drop OpTime " << opTime << " and rename it to namespace " << newNss
+                  << ": " << status;
+    }
+
+    return true;
+}
+
 void DropPendingCollectionReaper::dropCollectionsOlderThan(OperationContext* opCtx,
                                                            const OpTime& opTime) {
     DropPendingNamespaces toDrop;