SERVER-53224 Fix collection drop on donor shards for resharding.

3 files changed, 42 insertions, 24 deletions

diff --git a/src/mongo/db/s/resharding/resharding_data_copy_util.cpp b/src/mongo/db/s/resharding/resharding_data_copy_util.cpp
index bf59a4af30c..ad85a69d241 100644
--- a/src/mongo/db/s/resharding/resharding_data_copy_util.cpp
+++ b/src/mongo/db/s/resharding/resharding_data_copy_util.cpp
@@ -40,6 +40,7 @@
 namespace mongo::resharding::data_copy {
 
 void ensureCollectionExists(OperationContext* opCtx, const NamespaceString& nss) {
+    invariant(!opCtx->lockState()->isLocked());
     invariant(!opCtx->lockState()->inAWriteUnitOfWork());
 
     writeConflictRetry(opCtx, "resharding::data_copy::ensureCollectionExists", nss.toString(), [&] {
@@ -54,4 +55,25 @@ void ensureCollectionExists(OperationContext* opCtx, const NamespaceString& nss)
     });
 }
 
+void ensureCollectionDropped(OperationContext* opCtx,
+                             const NamespaceString& nss,
+                             const boost::optional<CollectionUUID>& uuid) {
+    invariant(!opCtx->lockState()->isLocked());
+    invariant(!opCtx->lockState()->inAWriteUnitOfWork());
+
+    writeConflictRetry(
+        opCtx, "resharding::data_copy::ensureCollectionDropped", nss.toString(), [&] {
+            AutoGetCollection coll(opCtx, nss, MODE_X);
+            if (!coll || (uuid && coll->uuid() != uuid)) {
+                // If the collection doesn't exist or exists with a different UUID, then the
+                // requested collection has been dropped already.
+                return;
+            }
+
+            WriteUnitOfWork wuow(opCtx);
+            uassertStatusOK(coll.getDb()->dropCollectionEvenIfSystem(opCtx, nss));
+            wuow.commit();
+        });
+}
+
 }  // namespace mongo::resharding::data_copy
diff --git a/src/mongo/db/s/resharding/resharding_data_copy_util.h b/src/mongo/db/s/resharding/resharding_data_copy_util.h
index 72ccd0cd8b1..22b96a1b26a 100644
--- a/src/mongo/db/s/resharding/resharding_data_copy_util.h
+++ b/src/mongo/db/s/resharding/resharding_data_copy_util.h
@@ -29,6 +29,10 @@
 
 #pragma once
 
+#include <boost/optional.hpp>
+
+#include "mongo/db/catalog/collection_catalog.h"
+
 namespace mongo {
 
 class NamespaceString;
@@ -38,5 +42,16 @@ namespace resharding::data_copy {
 
 void ensureCollectionExists(OperationContext* opCtx, const NamespaceString& nss);
 
+/**
+ * Drops the specified collection or returns without error if the collection has already been
+ * dropped. A particular incarnation of the collection can be dropped by specifying its UUID.
+ *
+ * This functions assumes the collection being dropped doesn't have any two-phase index builds
+ * active on it.
+ */
+void ensureCollectionDropped(OperationContext* opCtx,
+                             const NamespaceString& nss,
+                             const boost::optional<CollectionUUID>& uuid = boost::none);
+
 }  // namespace resharding::data_copy
 }  // namespace mongo
diff --git a/src/mongo/db/s/resharding/resharding_donor_service.cpp b/src/mongo/db/s/resharding/resharding_donor_service.cpp
index 8bece262499..18869850144 100644
--- a/src/mongo/db/s/resharding/resharding_donor_service.cpp
+++ b/src/mongo/db/s/resharding/resharding_donor_service.cpp
@@ -42,6 +42,7 @@
 #include "mongo/db/op_observer.h"
 #include "mongo/db/persistent_task_store.h"
 #include "mongo/db/repl/repl_client_info.h"
+#include "mongo/db/s/resharding/resharding_data_copy_util.h"
 #include "mongo/db/s/resharding/resharding_server_parameters_gen.h"
 #include "mongo/db/s/resharding_util.h"
 #include "mongo/db/s/sharding_state.h"
@@ -408,30 +409,10 @@ void ReshardingDonorService::DonorStateMachine::_dropOriginalCollection() {
         return;
     }
 
-    auto origNssRoutingInfo =
-        getShardedCollectionRoutingInfoWithRefreshAndFlush(_donorDoc.getNss());
-    auto currentCollectionUUID =
-        getCollectionUUIDFromChunkManger(_donorDoc.getNss(), origNssRoutingInfo);
-
-    if (currentCollectionUUID == _donorDoc.getExistingUUID()) {
-        DBDirectClient client(cc().makeOperationContext().get());
-        BSONObj dropResult;
-        if (!client.dropCollection(
-                _donorDoc.getNss().toString(), WriteConcerns::kMajorityWriteConcern, &dropResult)) {
-            auto dropStatus = getStatusFromCommandResult(dropResult);
-            if (dropStatus != ErrorCodes::NamespaceNotFound) {
-                uassertStatusOK(dropStatus);
-            }
-        }
-    } else {
-        uassert(ErrorCodes::InvalidUUID,
-                "Expected collection {} to have either the original UUID {} or the resharding UUID"
-                " {}, but the collection instead has UUID {}"_format(
-                    _donorDoc.getNss().toString(),
-                    _donorDoc.getExistingUUID().toString(),
-                    _donorDoc.get_id().toString(),
-                    currentCollectionUUID.toString()),
-                currentCollectionUUID == _donorDoc.get_id());
+    {
+        auto opCtx = cc().makeOperationContext();
+        resharding::data_copy::ensureCollectionDropped(
+            opCtx.get(), _donorDoc.getNss(), _donorDoc.getExistingUUID());
     }
 
     _transitionStateAndUpdateCoordinator(DonorStateEnum::kDone);