Improve version handling for user_migration

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

Author: come-nc

lib/public/UserMigration/IExportDestination.php

@@ -66,6 +66,13 @@ public function addFileAsStream(string $path, $stream): bool;
 	 */
 	public function copyFolder(Folder $folder, string $destinationPath): bool;
 
+	/**
+	 * @param array<string,int> $versions Migrators and their versions.
+	 *
+	 * @since 24.0.0
+	 */
+	public function setMigratorVersions(array $versions): bool;
+
 	/**
 	 * Called after export is complete
 	 *

lib/public/UserMigration/IImportSource.php

@@ -63,6 +63,13 @@ public function getFileAsStream(string $path);
 	 */
 	public function copyToFolder(Folder $destination, string $sourcePath): bool;
 
+	/**
+	 * @return array<string,int> Migrators and their versions from the export archive.
+	 *
+	 * @since 24.0.0
+	 */
+	public function getMigratorVersions(): array;
+
 	/**
 	 * Called after import is complete
 	 *

lib/public/UserMigration/IMigrator.php

@@ -54,7 +54,8 @@ public function export(
 	public function import(
 		IUser $user,
 		IImportSource $importSource,
-		OutputInterface $output
+		OutputInterface $output,
+		?int $version
 	): void;
 
 	/**
@@ -67,7 +68,12 @@ public function getVersion(): int;
 	/**
 	 * Checks whether it is able to import a version of the export format for this migrator
 	 *
+	 * @param ?int $version Version stored in the import source for this migrator. Null means this migrator was not listed.
+	 *
 	 * @since 24.0.0
 	 */
-	public function canImport(int $version): bool;
+	public function canImport(
+		IImportSource $importSource,
+		?int $version
+	): bool;
 }

lib/public/UserMigration/TMigratorBasicVersionHandling.php

@@ -32,6 +32,8 @@
 trait TMigratorBasicVersionHandling {
 	protected int $version = 1;
 
+	protected bool $mandatory = false;
+
 	/**
 	 * {@inheritDoc}
 	 */
@@ -42,7 +44,13 @@ public function getVersion(): int {
 	/**
 	 * {@inheritDoc}
 	 */
-	public function canImport(int $version): bool {
+	public function canImport(
+		IImportSource $importSource,
+		?int $version
+	): bool {
+		if ($version === null) {
+			return !$this->mandatory;
+		}
 		return ($this->version >= $version);
 	}
 }