SERVER-49915 Disable document validation for <database>.system.resharding.* namespaces

2 files changed, 38 insertions, 0 deletions

diff --git a/src/mongo/db/catalog/collection_impl.cpp b/src/mongo/db/catalog/collection_impl.cpp
index ebeb5af4c3b..30520fe8a54 100644
--- a/src/mongo/db/catalog/collection_impl.cpp
+++ b/src/mongo/db/catalog/collection_impl.cpp
@@ -206,6 +206,12 @@ Status checkValidatorCanBeUsedOnNs(const BSONObj& validator,
     if (validator.isEmpty())
         return Status::OK();
 
+    if (nss.isTemporaryReshardingCollection()) {
+        // In resharding, if the user's original collection has a validator, then the temporary
+        // resharding collection is created with it as well.
+        return Status::OK();
+    }
+
     if (nss.isSystem() && !nss.isDropPendingNamespace()) {
         return {ErrorCodes::InvalidOptions,
                 str::stream() << "Document validators not allowed on system collection " << nss
@@ -384,6 +390,13 @@ Status CollectionImpl::checkValidation(OperationContext* opCtx, const BSONObj& d
     if (documentValidationDisabled(opCtx))
         return Status::OK();
 
+    if (ns().isTemporaryReshardingCollection()) {
+        // In resharding, the donor shard primary is responsible for performing document validation
+        // and the recipient should not perform validation on documents inserted into the temporary
+        // resharding collection.
+        return Status::OK();
+    }
+
     if (validatorMatchExpr->matchesBSON(document))
         return Status::OK();
 
diff --git a/src/mongo/db/catalog/create_collection_test.cpp b/src/mongo/db/catalog/create_collection_test.cpp
index ea9bc5c02a5..cef79c84a45 100644
--- a/src/mongo/db/catalog/create_collection_test.cpp
+++ b/src/mongo/db/catalog/create_collection_test.cpp
@@ -271,4 +271,29 @@ TEST_F(CreateCollectionTest, ValidationOptions) {
     validateValidator("{$expr: {$_internalJsEmit: {eval: 'function() {}', this: {}}}}", 4660801);
     validateValidator("{$where: 'this.a == this.b'}", static_cast<int>(ErrorCodes::BadValue));
 }
+
+// Tests that validator validation is disabled when inserting a document into a
+// <database>.system.resharding.* collection. The primary donor is responsible for validating
+// documents before they are inserted into the recipient's temporary resharding collection.
+TEST_F(CreateCollectionTest, ValidationDisabledForTemporaryReshardingCollection) {
+    NamespaceString reshardingNss("myDb", "system.resharding.yay");
+    auto opCtx = makeOpCtx();
+
+    Lock::GlobalLock lk(opCtx.get(), MODE_X);  // Satisfy low-level locking invariants.
+    BSONObj createCmdObj = BSON("create" << reshardingNss.coll() << "validator" << BSON("a" << 5));
+    ASSERT_OK(createCollection(opCtx.get(), reshardingNss.db().toString(), createCmdObj));
+    ASSERT_TRUE(collectionExists(opCtx.get(), reshardingNss));
+
+    AutoGetCollection agc(opCtx.get(), reshardingNss, MODE_X);
+    Collection* collection = agc.getCollection();
+
+    WriteUnitOfWork wuow(opCtx.get());
+    // Ensure a document that violates validator criteria can be inserted into the temporary
+    // resharding collection.
+    auto insertObj = fromjson("{'_id':2, a:1}");
+    auto status =
+        collection->insertDocument(opCtx.get(), InsertStatement(insertObj), nullptr, false);
+    ASSERT_OK(status);
+}
+
 }  // namespace