Add export estimate endpoint

Signed-off-by: Christopher Ng <[email protected]>

appinfo/routes.php

@@ -33,7 +33,8 @@
 		['name' => 'Api#migrators', 'url' => '/api/v{apiVersion}/migrators', 'verb' => 'GET', 'requirements' => $requirements],
 		['name' => 'Api#status', 'url' => '/api/v{apiVersion}/status', 'verb' => 'GET', 'requirements' => $requirements],
 		['name' => 'Api#cancel', 'url' => '/api/v{apiVersion}/cancel', 'verb' => 'PUT', 'requirements' => $requirements],
-		['name' => 'Api#exportable', 'url' => '/api/v{apiVersion}/exportable', 'verb' => 'GET', 'requirements' => $requirements],
+		['name' => 'Api#estimate', 'url' => '/api/v{apiVersion}/export/estimate', 'verb' => 'GET', 'requirements' => $requirements],
+		['name' => 'Api#exportable', 'url' => '/api/v{apiVersion}/export', 'verb' => 'GET', 'requirements' => $requirements],
 		['name' => 'Api#export', 'url' => '/api/v{apiVersion}/export', 'verb' => 'POST', 'requirements' => $requirements],
 		['name' => 'Api#import', 'url' => '/api/v{apiVersion}/import', 'verb' => 'POST', 'requirements' => $requirements],
 	],

lib/Controller/ApiController.php

@@ -211,6 +211,28 @@ private function checkJobAndGetUser(): IUser {
 		return $user;
 	}
 
+	/**
+	 * @NoAdminRequired
+	 * @NoSubAdminRequired
+	 *
+	 * @throws OCSException
+	 */
+	public function estimate(?array $migrators): DataResponse {
+		$user = $this->checkJobAndGetUser();
+
+		if (!is_null($migrators)) {
+			$this->checkMigrators($migrators);
+		}
+
+		try {
+			$size = $this->migrationService->estimateExportSize($user, $migrators);
+		} catch (UserMigrationException $e) {
+			throw new OCSException($e->getMessage());
+		}
+
+		return new DataResponse(['size' => $size], Http::STATUS_OK);
+	}
+
 	/**
 	 * @NoAdminRequired
 	 * @NoSubAdminRequired

lib/Service/UserMigrationService.php

@@ -110,8 +110,10 @@ public function __construct(
 	 * @param ?string[] $filteredMigratorList If not null, only these migrators will run. If empty only the main account data will be exported.
 	 *
 	 * @return int Estimated size in KiB
+	 *
+	 * @throws UserMigrationException
 	 */
-	private function estimateExportSize(IUser $user, ?array $filteredMigratorList = null): int {
+	public function estimateExportSize(IUser $user, ?array $filteredMigratorList = null): int {
 		// 1MiB for base user data
 		$size = 1024;
 
@@ -125,7 +127,11 @@ private function estimateExportSize(IUser $user, ?array $filteredMigratorList =
 				continue;
 			}
 			if ($migrator instanceof ISizeEstimationMigrator) {
-				$migratorSize = $migrator->getEstimatedExportSize($user);
+				try {
+					$migratorSize = $migrator->getEstimatedExportSize($user);
+				} catch (Throwable $e) {
+					throw new UserMigrationException('Could not estimate export size for ' . $migrator->getDisplayName(), 0, $e);
+				}
 				$this->internalCache->set($cacheKey, $migratorSize);
 				$size += $migratorSize;
 			}