#pragma once #include #include #include #include namespace DB { /* Implements storage in the MongoDB database. * Use ENGINE = mysql(host_port, database_name, table_name, user_name, password) * Read only. */ class StorageMongoDB final : public shared_ptr_helper, public IStorage { friend struct shared_ptr_helper; public: StorageMongoDB( const StorageID & table_id_, const std::string & host_, uint16_t port_, const std::string & database_name_, const std::string & collection_name_, const std::string & username_, const std::string & password_, const std::string & options_, const ColumnsDescription & columns_, const ConstraintsDescription & constraints_, const String & comment); std::string getName() const override { return "MongoDB"; } Pipe read( const Names & column_names, const StorageSnapshotPtr & storage_snapshot, SelectQueryInfo & query_info, ContextPtr context, QueryProcessingStage::Enum processed_stage, size_t max_block_size, unsigned num_streams) override; static StorageMongoDBConfiguration getConfiguration(ASTs engine_args, ContextPtr context); private: void connectIfNotConnected(); const std::string host; const uint16_t port; /// NOLINT const std::string database_name; const std::string collection_name; const std::string username; const std::string password; const std::string options; const std::string uri; std::shared_ptr connection; bool authenticated = false; std::mutex connection_mutex; /// Protects the variables `connection` and `authenticated`. }; }