SERVER-57385 add BSONCollectionCatalogEntry::IndexMetaData::isPresent()

Ignore invalid index metadata when calculating total index count and returning all indexes.

4 files changed, 27 insertions, 4 deletions

diff --git a/src/mongo/db/catalog/collection_impl.cpp b/src/mongo/db/catalog/collection_impl.cpp
index 4138de412e7..54c08ad9f33 100644
--- a/src/mongo/db/catalog/collection_impl.cpp
+++ b/src/mongo/db/catalog/collection_impl.cpp
@@ -1965,7 +1965,7 @@ void CollectionImpl::forceSetIndexIsMultikey(OperationContext* opCtx,
 }
 
 int CollectionImpl::getTotalIndexCount() const {
-    return static_cast<int>(_metadata->indexes.size());
+    return _metadata->getTotalIndexCount();
 }
 
 int CollectionImpl::getCompletedIndexCount() const {
@@ -1987,8 +1987,12 @@ BSONObj CollectionImpl::getIndexSpec(StringData indexName) const {
 }
 
 void CollectionImpl::getAllIndexes(std::vector<std::string>* names) const {
-    for (unsigned i = 0; i < _metadata->indexes.size(); i++) {
-        names->push_back(_metadata->indexes[i].spec["name"].String());
+    for (const auto& index : _metadata->indexes) {
+        if (!index.isPresent()) {
+            continue;
+        }
+
+        names->push_back(index.nameStringData().toString());
     }
 }
 
diff --git a/src/mongo/db/storage/bson_collection_catalog_entry.cpp b/src/mongo/db/storage/bson_collection_catalog_entry.cpp
index 4fdf2f8baa5..1c954cbce9f 100644
--- a/src/mongo/db/storage/bson_collection_catalog_entry.cpp
+++ b/src/mongo/db/storage/bson_collection_catalog_entry.cpp
@@ -139,6 +139,11 @@ void BSONCollectionCatalogEntry::IndexMetaData::updateHiddenSetting(bool hidden)
 
 // --------------------------
 
+int BSONCollectionCatalogEntry::MetaData::getTotalIndexCount() const {
+    return std::count_if(
+        indexes.cbegin(), indexes.cend(), [](const auto& index) { return index.isPresent(); });
+}
+
 int BSONCollectionCatalogEntry::MetaData::findIndexOffset(StringData name) const {
     for (unsigned i = 0; i < indexes.size(); i++)
         if (indexes[i].nameStringData() == name)
diff --git a/src/mongo/db/storage/bson_collection_catalog_entry.h b/src/mongo/db/storage/bson_collection_catalog_entry.h
index 189565eaff1..afdfc310e1b 100644
--- a/src/mongo/db/storage/bson_collection_catalog_entry.h
+++ b/src/mongo/db/storage/bson_collection_catalog_entry.h
@@ -69,6 +69,15 @@ public:
             multikeyPaths = other.multikeyPaths;
         }
 
+        /**
+         * An index is considered present if it has a non-empty 'spec'.
+         * Invalid indexes by this definition include default constructed instances and
+         * and structs zeroed out due to index drops.
+         */
+        bool isPresent() const {
+            return !spec.isEmpty();
+        }
+
         IndexMetaData& operator=(IndexMetaData&& rhs) {
             if (&rhs != this) {
                 spec = std::move(rhs.spec);
@@ -122,6 +131,11 @@ public:
          */
         BSONObj toBSON(bool hasExclusiveAccess = false) const;
 
+        /**
+         * Returns number of valid indexes.
+         */
+        int getTotalIndexCount() const;
+
         int findIndexOffset(StringData name) const;
 
         /**
diff --git a/src/mongo/db/storage/durable_catalog_impl.cpp b/src/mongo/db/storage/durable_catalog_impl.cpp
index cd806d06b0a..bf9818d25e9 100644
--- a/src/mongo/db/storage/durable_catalog_impl.cpp
+++ b/src/mongo/db/storage/durable_catalog_impl.cpp
@@ -1070,7 +1070,7 @@ int DurableCatalogImpl::getTotalIndexCount(OperationContext* opCtx, RecordId cat
     if (!md)
         return 0;
 
-    return static_cast<int>(md->indexes.size());
+    return md->getTotalIndexCount();
 }
 
 bool DurableCatalogImpl::isIndexPresent(OperationContext* opCtx,