From f8e6468a7b2eb6f02026840a77fa7b9e586690b3 Mon Sep 17 00:00:00 2001
From: Kishore Nallan <kishorenc@gmail.com>
Date: Mon, 21 Aug 2023 12:29:40 +0530
Subject: [PATCH] Better guards for top_k truncation.

---
 src/collection.cpp | 4 ++++
 src/index.cpp      | 3 ++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/collection.cpp b/src/collection.cpp
index 5d92b5b9..50aa82fe 100644
--- a/src/collection.cpp
+++ b/src/collection.cpp
@@ -4953,9 +4953,13 @@ void Collection::hide_credential(nlohmann::json& json, const std::string& creden
     }
 }
 Option<bool> Collection::truncate_after_top_k(const string &field_name, size_t k) {
+    std::shared_lock slock(mutex);
+
     std::vector<uint32_t> seq_ids;
     auto op = index->seq_ids_outside_top_k(field_name, k, seq_ids);
 
+    slock.unlock();
+
     if(!op.ok()) {
         return op;
     }
diff --git a/src/index.cpp b/src/index.cpp
index 2f8be825..84e9f6ed 100644
--- a/src/index.cpp
+++ b/src/index.cpp
@@ -6315,9 +6315,10 @@ size_t Index::num_seq_ids() const {
 
 Option<bool> Index::seq_ids_outside_top_k(const std::string& field_name, size_t k,
                                           std::vector<uint32_t>& outside_seq_ids) {
+    std::shared_lock lock(mutex);
     auto field_it = numerical_index.find(field_name);
 
-    if(field_it == sort_index.end()) {
+    if(field_it == numerical_index.end()) {
         return Option<bool>(400, "Field not found in numerical index.");
     }