fix: fix index loading

src/server/search/doc_index.cc

@@ -11,6 +11,7 @@
 #include "base/logging.h"
 #include "server/engine_shard_set.h"
 #include "server/search/doc_accessors.h"
+#include "server/server_state.h"
 
 extern "C" {
 #include "redis/object.h"
@@ -150,10 +151,13 @@ bool DocIndex::Matches(string_view key, unsigned obj_code) const {
 }
 
 ShardDocIndex::ShardDocIndex(shared_ptr<DocIndex> index)
-    : base_{index}, indices_{index->schema}, key_index_{} {
+    : base_{std::move(index)}, indices_{{}}, key_index_{} {
 }
 
-void ShardDocIndex::Init(const OpArgs& op_args) {
+void ShardDocIndex::Rebuild(const OpArgs& op_args) {
+  key_index_ = DocKeyIndex{};
+  indices_ = search::FieldIndices{base_->schema};
+
   auto cb = [this](string_view key, BaseAccessor* doc) { indices_.Add(key_index_.Add(key), doc); };
   TraverseAllMatching(*base_, op_args, cb);
 }
@@ -213,7 +217,11 @@ void ShardDocIndices::InitIndex(const OpArgs& op_args, std::string_view name,
                                 shared_ptr<DocIndex> index_ptr) {
   auto shard_index = make_unique<ShardDocIndex>(index_ptr);
   auto [it, _] = indices_.emplace(name, move(shard_index));
-  it->second->Init(op_args);
+
+  // Don't build while loading, shutting down, etc.
+  // After loading, indices are rebuilt separately
+  if (ServerState::tlocal()->gstate() == GlobalState::ACTIVE)
+    it->second->Rebuild(op_args);
 
   op_args.shard->db_slice().SetDocDeletionCallback(
       [this](string_view key, const DbContext& cntx, const PrimeValue& pv) {
@@ -235,6 +243,11 @@ bool ShardDocIndices::DropIndex(string_view name) {
   return true;
 }
 
+void ShardDocIndices::RebuildAllIndices(const OpArgs& op_args) {
+  for (auto& [_, ptr] : indices_)
+    ptr->Rebuild(op_args);
+}
+
 vector<string> ShardDocIndices::GetIndexNames() const {
   vector<string> names{};
   names.reserve(indices_.size());

src/server/search/doc_index.h

@@ -75,6 +75,7 @@ class ShardDocIndex {
   struct DocKeyIndex {
     DocId Add(std::string_view key);
     DocId Remove(std::string_view key);
+
     std::string_view Get(DocId id) const;
     size_t Size() const;
 
@@ -86,14 +87,15 @@ class ShardDocIndex {
   };
 
  public:
+  // Index must be rebuilt at least once after intialization
   ShardDocIndex(std::shared_ptr<DocIndex> index);
 
   // Perform search on all indexed documents and return results.
   SearchResult Search(const OpArgs& op_args, const SearchParams& params,
                       search::SearchAlgorithm* search_algo) const;
 
-  // Initialize index. Traverses all matching documents and assigns ids.
-  void Init(const OpArgs& op_args);
+  // Clears internal data. Traverses all matching documents and assigns ids.
+  void Rebuild(const OpArgs& op_args);
 
   // Return whether base index matches
   bool Matches(std::string_view key, unsigned obj_code) const;
@@ -114,11 +116,17 @@ class ShardDocIndices {
  public:
   // Get sharded document index by its name or nullptr if not found
   ShardDocIndex* GetIndex(std::string_view name);
-  // Init index: create shard local state for given index with given name
+
+  // Init index: create shard local state for given index with given name.
+  // Build if instance is in active state.
   void InitIndex(const OpArgs& op_args, std::string_view name, std::shared_ptr<DocIndex> index);
+
   // Drop index, return true if it existed and was dropped
   bool DropIndex(std::string_view name);
 
+  // Rebuild all indices
+  void RebuildAllIndices(const OpArgs& op_args);
+
   std::vector<std::string> GetIndexNames() const;
 
   void AddDoc(std::string_view key, const DbContext& db_cnt, const PrimeValue& pv);

src/server/server_family.cc

@@ -779,6 +779,15 @@ struct SaveStagesController : public SaveStagesInputs {
   Mutex rdb_name_map_mu_;
 };
 
+void RebuildAllSearchIndices(Service* service) {
+  boost::intrusive_ptr<Transaction> trans{new Transaction{service->FindCmd("FT.CREATE")}};
+  trans->InitByArgs(0, {});
+  trans->ScheduleSingleHop([](auto* trans, auto* es) {
+    es->search_indices()->RebuildAllIndices(trans->GetOpArgs(es));
+    return OpStatus::OK;
+  });
+}
+
 }  // namespace
 
 std::optional<SnapshotSpec> ParseSaveSchedule(string_view time) {
@@ -1073,6 +1082,8 @@ Future<std::error_code> ServerFamily::Load(const std::string& load_path) {
       fiber.Join();
     }
 
+    RebuildAllSearchIndices(&service_);
+
     LOG(INFO) << "Load finished, num keys read: " << aggregated_result->keys_read;
     service_.SwitchState(GlobalState::LOADING, GlobalState::ACTIVE);
     ec_promise.set_value(*(aggregated_result->first_error));