Files
data-raft/Sources/DataRaft/Protocols/MigrationServiceProtocol.swift
2025-11-09 15:58:05 +02:00

62 lines
2.3 KiB
Swift

import Foundation
/// A type that manages and executes database schema migrations.
///
/// ## Overview
///
/// Conforming types are responsible for registering migration steps, applying encryption keys
/// (if required), and executing pending migrations in ascending version order. Migrations ensure
/// that the database schema evolves consistently across application versions without manual
/// intervention.
///
/// ## Topics
///
/// ### Associated Types
/// - ``Version``
///
/// ### Properties
/// - ``keyProvider``
///
/// ### Instance Methods
/// - ``add(_:)``
/// - ``migrate()``
/// - ``migrate()-18x5r``
public protocol MigrationServiceProtocol: AnyObject, Sendable {
/// The type representing a schema version used for migrations.
associatedtype Version: VersionRepresentable
/// The provider responsible for supplying encryption keys to the service.
var keyProvider: ConnectionServiceKeyProvider? { get set }
/// Registers a migration to be executed by the service.
///
/// - Parameter migration: The migration to register.
/// - Throws: ``MigrationError/duplicateMigration(_:)`` if a migration with the same version
/// or script URL is already registered.
func add(_ migration: Migration<Version>) throws(MigrationError<Version>)
/// Executes all pending migrations in ascending version order.
///
/// - Throws: ``MigrationError/emptyMigrationScript(_:)`` if a migration script is empty.
/// - Throws: ``MigrationError/migrationFailed(_:_:)`` if a migration step fails to execute
/// or update the stored version.
func migrate() throws(MigrationError<Version>)
}
@available(iOS 13.0, macOS 10.15, *)
public extension MigrationServiceProtocol {
/// Asynchronously executes all pending migrations in ascending version order.
///
/// Performs the same logic as ``migrate()``, but runs asynchronously on a background task with
/// `.utility` priority.
///
/// - Throws: ``MigrationError/emptyMigrationScript(_:)`` if a migration script is empty.
/// - Throws: ``MigrationError/migrationFailed(_:_:)`` if a migration step fails to execute
/// or update the stored version.
func migrate() async throws {
try await Task(priority: .utility) {
try self.migrate()
}.value
}
}