SERVER-63474 Do not recompute the ShardKeyPattern

1 files changed, 9 insertions, 13 deletions

diff --git a/src/mongo/db/exec/shard_filterer_impl.cpp b/src/mongo/db/exec/shard_filterer_impl.cpp
index 577883c1bf6..ebe4f2a52a8 100644
--- a/src/mongo/db/exec/shard_filterer_impl.cpp
+++ b/src/mongo/db/exec/shard_filterer_impl.cpp
@@ -40,11 +40,8 @@ std::unique_ptr<ShardFilterer> ShardFiltererImpl::clone() const {
     return std::make_unique<ShardFiltererImpl>(_collectionFilter);
 }
 
-ShardFiltererImpl::ShardFiltererImpl(ScopedCollectionFilter cf) : _collectionFilter(std::move(cf)) {
-    if (_collectionFilter.isSharded()) {
-        _keyPattern = ShardKeyPattern(_collectionFilter.getKeyPattern());
-    }
-}
+ShardFiltererImpl::ShardFiltererImpl(ScopedCollectionFilter cf)
+    : _collectionFilter(std::move(cf)) {}
 
 ShardFilterer::DocumentBelongsResult ShardFiltererImpl::keyBelongsToMeHelper(
     const BSONObj& shardKey) const {
@@ -63,7 +60,8 @@ ShardFilterer::DocumentBelongsResult ShardFiltererImpl::documentBelongsToMe(
     }
 
     if (wsm.hasObj()) {
-        return keyBelongsToMeHelper(_keyPattern->extractShardKeyFromDoc(wsm.doc.value().toBson()));
+        return keyBelongsToMeHelper(_collectionFilter.getShardKeyPattern().extractShardKeyFromDoc(
+            wsm.doc.value().toBson()));
     }
     // Transform 'IndexKeyDatum' provided by 'wsm' into 'IndexKeyData' to call
     // extractShardKeyFromIndexKeyData().
@@ -73,7 +71,8 @@ ShardFilterer::DocumentBelongsResult ShardFiltererImpl::documentBelongsToMe(
     for (auto&& indexKeyData : wsm.keyData) {
         indexKeyDataVector.push_back({indexKeyData.keyData, indexKeyData.indexKeyPattern});
     }
-    return keyBelongsToMeHelper(_keyPattern->extractShardKeyFromIndexKeyData(indexKeyDataVector));
+    return keyBelongsToMeHelper(
+        _collectionFilter.getShardKeyPattern().extractShardKeyFromIndexKeyData(indexKeyDataVector));
 }
 
 ShardFilterer::DocumentBelongsResult ShardFiltererImpl::documentBelongsToMe(
@@ -81,19 +80,16 @@ ShardFilterer::DocumentBelongsResult ShardFiltererImpl::documentBelongsToMe(
     if (!_collectionFilter.isSharded()) {
         return DocumentBelongsResult::kBelongs;
     }
-    return keyBelongsToMeHelper(_keyPattern->extractShardKeyFromDoc(doc));
+    return keyBelongsToMeHelper(_collectionFilter.getShardKeyPattern().extractShardKeyFromDoc(doc));
 }
 
 const KeyPattern& ShardFiltererImpl::getKeyPattern() const {
-    invariant(_keyPattern);
-    return _keyPattern->getKeyPattern();
+    return _collectionFilter.getShardKeyPattern().getKeyPattern();
 }
 
 size_t ShardFiltererImpl::getApproximateSize() const {
     // _collectionFilter contains a pointer to metadata but it doesn't own this metadata, so we
     // don't account for the size of the metadata here.
-    auto size = sizeof(ShardFiltererImpl);
-    size += _keyPattern ? _keyPattern->getApproximateSize() - sizeof(ShardKeyPattern) : 0;
-    return size;
+    return sizeof(ShardFiltererImpl);
 }
 }  // namespace mongo