transaction_config.go

/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [https://neo4j.com]
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package neo4j

import "time"

// TransactionConfig holds the settings for explicit and auto-commit transactions. Actual configuration is expected
// to be done using configuration functions that are predefined, i.e. 'WithTxTimeout' and 'WithTxMetadata', or one
// that you could write by your own.
type TransactionConfig struct {
	// Timeout is the configured transaction timeout.
	Timeout time.Duration
	// Metadata is the configured transaction metadata that will be attached to the underlying transaction.
	Metadata map[string]any
}

// WithTxTimeout returns a transaction configuration function that applies a timeout to a transaction.
//
// Transactions that execute longer than the configured timeout will be terminated by the database.
// This functionality allows user code to limit query/transaction execution time.
// The specified timeout overrides the default timeout configured in the database using the `db.transaction.timeout`
// setting (`dbms.transaction.timeout` before Neo4j 5.0).
// Values higher than `db.transaction.timeout` will be ignored and will fall back to the default for server versions
// between 4.2 and 5.2 (inclusive).
// A `0` duration will make the transaction execute indefinitely.
// `math.MinInt` will use the default timeout configured on the server.
// Other negative durations are invalid.
//
// To apply a transaction timeout to an explicit transaction:
//
//	session.BeginTransaction(WithTxTimeout(5*time.Second))
//
// To apply a transaction timeout to an auto-commit transaction:
//
//	session.Run("RETURN 1", nil, WithTxTimeout(5*time.Second))
//
// To apply a transaction timeout to a read transaction function:
//
//	session.ExecuteRead(DoWork, WithTxTimeout(5*time.Second))
//
// To apply a transaction timeout to a write transaction function:
//
//	session.ExecuteWrite(DoWork, WithTxTimeout(5*time.Second))
//
// To apply a transaction timeout with the ExecuteQuery function, use ExecuteQueryWithTransactionConfig:
//
//	ExecuteQuery(ctx, driver, query, parameters, transformer,
//		ExecuteQueryWithTransactionConfig(WithTxTimeout(*time.Second))
//	)
func WithTxTimeout(timeout time.Duration) func(*TransactionConfig) {
	return func(config *TransactionConfig) {
		config.Timeout = timeout
	}
}

// WithTxMetadata returns a transaction configuration function that attaches metadata to a transaction.
//
// To attach metadata to an explicit transaction:
//
//	session.BeginTransaction(WithTxMetadata(map[string]any{"work-id": 1}))
//
// To attach metadata to an auto-commit transaction:
//
//	session.Run("RETURN 1", nil, WithTxMetadata(map[string]any{"work-id": 1}))
//
// To attach metadata to a read transaction function:
//
//	session.ExecuteRead(DoWork, WithTxMetadata(map[string]any{"work-id": 1}))
//
// To attach metadata to a write transaction function:
//
//	session.ExecuteWrite(DoWork, WithTxMetadata(map[string]any{"work-id": 1}))
//
// To attach metadata with the ExecuteQuery function, use ExecuteQueryWithTransactionConfig:
//
//	ExecuteQuery(ctx, driver, query, parameters, transformer,
//		ExecuteQueryWithTransactionConfig(WithTxMetadata(map[string]any{"work-id": 1}))
//	)
func WithTxMetadata(metadata map[string]any) func(*TransactionConfig) {
	return func(config *TransactionConfig) {
		config.Metadata = metadata
	}
}