Files
data-raft/Sources/DataRaft/Protocols/DatabaseServiceProtocol.swift

68 lines
2.6 KiB
Swift

import Foundation
import DataLiteCore
/// A protocol for a database service.
///
/// `DatabaseServiceProtocol` defines the core capabilities required for
/// reliable interaction with a database. Conforming implementations provide
/// execution of client closures with a live connection, transaction wrapping,
/// reconnection logic, and flexible encryption key management.
///
/// This enables building safe and extensible service layers on top of
/// a database.
///
/// ## Topics
///
/// ### Key Management
///
/// - ``DatabaseServiceKeyProvider``
/// - ``keyProvider``
///
/// ### Database Operations
///
/// - ``Perform``
/// - ``perform(_:)``
/// - ``perform(in:closure:)``
public protocol DatabaseServiceProtocol: AnyObject, Sendable {
/// A closure executed with an active database connection.
///
/// Used by the service to safely provide access to `Connection`
/// within the appropriate execution context.
///
/// - Parameter connection: The active database connection.
/// - Returns: The value returned by the closure.
/// - Throws: An error if the closure execution fails.
typealias Perform<T> = (Connection) throws -> T
/// The encryption key provider for the database service.
///
/// Enables external management of encryption keys.
/// When set, the service can request a key when establishing or
/// restoring a connection, and can also notify about errors
/// encountered while applying a key.
var keyProvider: DatabaseServiceKeyProvider? { get set }
/// Executes the given closure with an active connection.
///
/// The closure receives the connection and may perform any
/// database operations within the current context.
///
/// - Parameter closure: The closure that accepts a connection.
/// - Returns: The value returned by the closure.
/// - Throws: An error if one occurs during closure execution.
func perform<T>(_ closure: Perform<T>) throws -> T
/// Executes the given closure within a transaction.
///
/// If the connection is in autocommit mode, the method automatically
/// begins a transaction, executes the closure, and commits the changes.
/// In case of failure, the transaction is rolled back.
///
/// - Parameters:
/// - transaction: The type of transaction to begin.
/// - closure: The closure that accepts a connection.
/// - Returns: The value returned by the closure.
/// - Throws: An error if one occurs during closure execution.
func perform<T>(in transaction: TransactionType, closure: Perform<T>) throws -> T
}