let graph_id increasing, don't use previous ids

Committed-by: xiaolei.zl from Dev container

flex/engines/http_server/handler/graph_db_http_handler.cc

@@ -176,7 +176,7 @@ class stored_proc_handler : public StoppableHandler {
 
   bool start() override {
     if (get_executors()[StoppableHandler::shard_id()].size() > 0) {
-      VLOG(1) << "The actors have been already created!";
+      VLOG(10) << "The actors have been already created!";
       return false;
     }
     return StoppableHandler::start_scope(

flex/storages/metadata/local_file_metadata_store.cc

@@ -181,8 +181,8 @@ Result<bool> LocalFileMetadataStore::UpdateMeta(const meta_kind_t& meta_kind,
 
 Result<LocalFileMetadataStore::meta_key_t>
 LocalFileMetadataStore::get_next_meta_key(
-    const LocalFileMetadataStore::meta_kind_t& meta_kind) const {
-  return std::to_string(get_max_id(meta_kind) + 1);
+    const LocalFileMetadataStore::meta_kind_t& meta_kind) {
+  return std::to_string(increase_and_get_id(meta_kind));
 }
 
 std::string LocalFileMetadataStore::get_root_meta_dir() const {
@@ -208,29 +208,38 @@ std::string LocalFileMetadataStore::get_meta_file(const meta_kind_t& meta_kind,
   return ret;
 }
 
-int32_t LocalFileMetadataStore::get_max_id(const meta_kind_t& meta_kind) const {
-  // iterate all files in the directory, get the max id.
-  int max_id_ = 0;
+// Guarded by meta_mutex_ outside.
+int32_t LocalFileMetadataStore::increase_and_get_id(
+    const meta_kind_t& meta_kind) {
   auto dir = get_meta_kind_dir(meta_kind);
-  for (auto& p : std::filesystem::directory_iterator(dir)) {
-    if (std::filesystem::is_directory(p)) {
-      continue;
-    }
-    auto file_name = p.path().filename().string();
-    if (file_name.find(META_FILE_PREFIX) != std::string::npos) {
-      auto id_str = file_name.substr(strlen(META_FILE_PREFIX));
-      int32_t id;
-      try {
-        id = std::stoi(id_str);
-      } catch (std::invalid_argument& e) {
-        LOG(ERROR) << "Invalid id: " << id_str;
-        continue;
-      }
-      if (id > max_id_) {
-        max_id_ = id;
-      }
+  int max_id_ = 0;
+  // In the directory, we expect a file with name CUR_ID_FILE_NAME.
+  // If the file does not exist, we will create one with content "0".
+  auto cur_id_file = dir + "/" + CUR_ID_FILE_NAME;
+  if (!std::filesystem::exists(cur_id_file)) {
+    std::ofstream out_file(cur_id_file);
+    if (!out_file.is_open()) {
+      LOG(ERROR) << "Failed to create file: " << cur_id_file;
+      return -1;
     }
+    out_file << "0";
+    out_file.close();
+  }
+  std::ifstream in_file(cur_id_file);
+  if (!in_file.is_open()) {
+    LOG(ERROR) << "Failed to open file: " << cur_id_file;
+    return -1;
   }
+  in_file >> max_id_;
+  in_file.close();
+  max_id_++;
+  std::ofstream out_file(cur_id_file);
+  if (!out_file.is_open()) {
+    LOG(ERROR) << "Failed to open file: " << cur_id_file;
+    return -1;
+  }
+  out_file << max_id_;
+  out_file.close();
   return max_id_;
 }
 

flex/storages/metadata/local_file_metadata_store.h

@@ -48,6 +48,7 @@ class LocalFileMetadataStore : public IMetaStore {
 
   static constexpr const char* METADATA_DIR = "METADATA";
   static constexpr const char* META_FILE_PREFIX = "META_";
+  static constexpr const char* CUR_ID_FILE_NAME = "CUR_ID";
 
   LocalFileMetadataStore(const std::string& path);
 
@@ -110,12 +111,15 @@ class LocalFileMetadataStore : public IMetaStore {
                           update_func_t update_func) override;
 
  private:
-  Result<meta_key_t> get_next_meta_key(const meta_kind_t& meta_kind) const;
+  Result<meta_key_t> get_next_meta_key(const meta_kind_t& meta_kind);
   std::string get_root_meta_dir() const;
   std::string get_meta_kind_dir(const meta_kind_t& meta_kind) const;
   std::string get_meta_file(const meta_kind_t& meta_kind,
                             const meta_key_t& meta_key) const;
-  int32_t get_max_id(const meta_kind_t& meta_kind) const;
+  /**
+   * For the specified meta_kind, increase the id and return the new id.
+   */
+  int32_t increase_and_get_id(const meta_kind_t& meta_kind);
   bool is_key_exist(const meta_kind_t& meta_kind,
                     const meta_key_t& meta_key) const;
 

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/meta/GraphId.java

@@ -51,4 +51,9 @@ public boolean equals(Object o) {
     public int hashCode() {
         return Objects.hashCode(id);
     }
+
+    @Override
+    public String toString() {
+        return "GraphId{" + "id=" + id + '}';
+    }
 }

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/meta/fetcher/DynamicIrMetaFetcher.java

@@ -82,24 +82,22 @@ private synchronized void syncMeta() {
             logger.info(
                     "schema from remote: {}",
                     (meta == null) ? null : meta.getSchema().getSchemaSpec(Type.IR_CORE_IN_JSON));
-            // NOTE(lei): We could not use graph id to determine whether the graph is
-            // changed. Because the graph id is generated by the graph store, it may be
-            // different. So currently we need to update the schema and statistics every time.
-            // if (this.currentState == null
-            // || !this.currentState.getGraphId().equals(meta.getGraphId())
-            // || !this.currentState
-            //         .getSchema()
-            //         .getVersion()
-            //         .equals(meta.getSchema().getVersion())) {
-            this.statsState = StatsState.INITIALIZED;
-            this.currentState =
-                    new IrMetaStats(
-                            meta.getGraphId(),
-                            meta.getSnapshotId(),
-                            meta.getSchema(),
-                            meta.getStoredProcedures(),
-                            null);
-            // }
+            // if the graph id or schema version is changed, we need to update the statistics
+            if (this.currentState == null
+                    || !this.currentState.getGraphId().equals(meta.getGraphId())
+                    || !this.currentState
+                            .getSchema()
+                            .getVersion()
+                            .equals(meta.getSchema().getVersion())) {
+                this.statsState = StatsState.INITIALIZED;
+                this.currentState =
+                        new IrMetaStats(
+                                meta.getGraphId(),
+                                meta.getSnapshotId(),
+                                meta.getSchema(),
+                                meta.getStoredProcedures(),
+                                null);
+            }
             boolean statsEnabled = getStatsEnabled(this.currentState.getGraphId());
             if (statsEnabled && this.statsState != StatsState.SYNCED
                     || (!statsEnabled && this.statsState != StatsState.MOCKED)) {