Introduce BackendService for managing external storage backends

Backends are registered to the BackendService through new data
structures:

Backends are concrete classes, deriving from
\OCA\Files_External\Lib\Backend\Backend. During construction, the
various configuration parameters of the Backend can be set, in a design
similar to Symfony Console.

DefinitionParameter stores a parameter configuration for an external
storage: name of parameter, human-readable name, type of parameter
(text, password, hidden, checkbox), flags (optional or not).

Storages in the StoragesController now get their parameters validated
server-side (fixes a TODO).

3 files changed, 80 insertions, 36 deletions

diff --git a/apps/files_external/tests/controller/globalstoragescontrollertest.php b/apps/files_external/tests/controller/globalstoragescontrollertest.php
index fc58743454a..e1bfad8caf6 100644
--- a/apps/files_external/tests/controller/globalstoragescontrollertest.php
+++ b/apps/files_external/tests/controller/globalstoragescontrollertest.php
@@ -28,7 +28,9 @@ use \OCA\Files_external\NotFoundException;
 class GlobalStoragesControllerTest extends StoragesControllerTest {
 	public function setUp() {
 		parent::setUp();
-		$this->service = $this->getMock('\OCA\Files_external\Service\GlobalStoragesService');
+		$this->service = $this->getMockBuilder('\OCA\Files_external\Service\GlobalStoragesService')
+			->disableOriginalConstructor()
+			->getMock();
 
 		$this->controller = new GlobalStoragesController(
 			'files_external',
diff --git a/apps/files_external/tests/controller/storagescontrollertest.php b/apps/files_external/tests/controller/storagescontrollertest.php
index 86874ef9786..f3e8c9afbac 100644
--- a/apps/files_external/tests/controller/storagescontrollertest.php
+++ b/apps/files_external/tests/controller/storagescontrollertest.php
@@ -47,11 +47,33 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 		\OC_Mount_Config::$skipTest = false;
 	}
 
+	protected function getBackendMock($class = '\OCA\Files_External\Lib\Backend\SMB', $storageClass = '\OC\Files\Storage\SMB') {
+		$backend = $this->getMockBuilder('\OCA\Files_External\Lib\Backend\Backend')
+			->disableOriginalConstructor()
+			->getMock();
+		$backend->method('getStorageClass')
+			->willReturn($storageClass);
+		$backend->method('getClass')
+			->willReturn($storageClass);
+		return $backend;
+	}
+
 	public function testAddStorage() {
+		$backend = $this->getBackendMock();
+		$backend->method('validateStorage')
+			->willReturn(true);
+		$backend->method('isVisibleFor')
+			->willReturn(true);
+
 		$storageConfig = new StorageConfig(1);
 		$storageConfig->setMountPoint('mount');
+		$storageConfig->setBackend($backend);
+		$storageConfig->setBackendOptions([]);
 
 		$this->service->expects($this->once())
+			->method('createStorage')
+			->will($this->returnValue($storageConfig));
+		$this->service->expects($this->once())
 			->method('addStorage')
 			->will($this->returnValue($storageConfig));
 
@@ -71,10 +93,21 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 	}
 
 	public function testUpdateStorage() {
+		$backend = $this->getBackendMock();
+		$backend->method('validateStorage')
+			->willReturn(true);
+		$backend->method('isVisibleFor')
+			->willReturn(true);
+
 		$storageConfig = new StorageConfig(1);
 		$storageConfig->setMountPoint('mount');
+		$storageConfig->setBackend($backend);
+		$storageConfig->setBackendOptions([]);
 
 		$this->service->expects($this->once())
+			->method('createStorage')
+			->will($this->returnValue($storageConfig));
+		$this->service->expects($this->once())
 			->method('updateStorage')
 			->will($this->returnValue($storageConfig));
 
@@ -106,6 +139,14 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 	 * @dataProvider mountPointNamesProvider
 	 */
 	public function testAddOrUpdateStorageInvalidMountPoint($mountPoint) {
+		$storageConfig = new StorageConfig(1);
+		$storageConfig->setMountPoint($mountPoint);
+		$storageConfig->setBackend($this->getBackendMock());
+		$storageConfig->setBackendOptions([]);
+
+		$this->service->expects($this->exactly(2))
+			->method('createStorage')
+			->will($this->returnValue($storageConfig));
 		$this->service->expects($this->never())
 			->method('addStorage');
 		$this->service->expects($this->never())
@@ -138,6 +179,9 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 	}
 
 	public function testAddOrUpdateStorageInvalidBackend() {
+		$this->service->expects($this->exactly(2))
+			->method('createStorage')
+			->will($this->throwException(new \InvalidArgumentException()));
 		$this->service->expects($this->never())
 			->method('addStorage');
 		$this->service->expects($this->never())
@@ -170,6 +214,20 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 	}
 
 	public function testUpdateStorageNonExisting() {
+		$backend = $this->getBackendMock();
+		$backend->method('validateStorage')
+			->willReturn(true);
+		$backend->method('isVisibleFor')
+			->willReturn(true);
+
+		$storageConfig = new StorageConfig(255);
+		$storageConfig->setMountPoint('mount');
+		$storageConfig->setBackend($backend);
+		$storageConfig->setBackendOptions([]);
+
+		$this->service->expects($this->once())
+			->method('createStorage')
+			->will($this->returnValue($storageConfig));
 		$this->service->expects($this->once())
 			->method('updateStorage')
 			->will($this->throwException(new NotFoundException()));
@@ -206,9 +264,10 @@ abstract class StoragesControllerTest extends \Test\TestCase {
 	}
 
 	public function testGetStorage() {
+		$backend = $this->getBackendMock();
 		$storageConfig = new StorageConfig(1);
 		$storageConfig->setMountPoint('test');
-		$storageConfig->setBackendClass('\OC\Files\Storage\SMB');
+		$storageConfig->setBackend($backend);
 		$storageConfig->setBackendOptions(['user' => 'test', 'password', 'password123']);
 		$storageConfig->setMountOptions(['priority' => false]);
 
diff --git a/apps/files_external/tests/controller/userstoragescontrollertest.php b/apps/files_external/tests/controller/userstoragescontrollertest.php
index f9b4c5b2681..99825f26394 100644
--- a/apps/files_external/tests/controller/userstoragescontrollertest.php
+++ b/apps/files_external/tests/controller/userstoragescontrollertest.php
@@ -24,6 +24,8 @@ use \OCA\Files_external\Controller\UserStoragesController;
 use \OCA\Files_external\Service\UserStoragesService;
 use \OCP\AppFramework\Http;
 use \OCA\Files_external\NotFoundException;
+use \OCA\Files_External\Lib\StorageConfig;
+use \OCA\Files_External\Service\BackendService;
 
 class UserStoragesControllerTest extends StoragesControllerTest {
 
@@ -44,41 +46,22 @@ class UserStoragesControllerTest extends StoragesControllerTest {
 			$this->getMock('\OCP\IL10N'),
 			$this->service
 		);
-
-		$config = \OC::$server->getConfig();
-
-		$this->oldAllowedBackends = $config->getAppValue(
-			'files_external',
-			'user_mounting_backends',
-			''
-		);
-		$config->setAppValue(
-			'files_external',
-			'user_mounting_backends',
-			'\OC\Files\Storage\SMB'
-		);
 	}
 
-	public function tearDown() {
-		$config = \OC::$server->getConfig();
-		$config->setAppValue(
-			'files_external',
-			'user_mounting_backends',
-			$this->oldAllowedBackends
-		);
-		parent::tearDown();
-	}
+	public function testAddOrUpdateStorageDisallowedBackend() {
+		$backend = $this->getBackendMock();
+		$backend->method('isVisibleFor')
+			->with(BackendService::VISIBILITY_PERSONAL)
+			->willReturn(false);
 
-	function disallowedBackendClassProvider() {
-		return array(
-			array('\OC\Files\Storage\Local'),
-			array('\OC\Files\Storage\FTP'),
-		);
-	}
-	/**
-	 * @dataProvider disallowedBackendClassProvider
-	 */
-	public function testAddOrUpdateStorageDisallowedBackend($backendClass) {
+		$storageConfig = new StorageConfig(1);
+		$storageConfig->setMountPoint('mount');
+		$storageConfig->setBackend($backend);
+		$storageConfig->setBackendOptions([]);
+
+		$this->service->expects($this->exactly(2))
+			->method('createStorage')
+			->will($this->returnValue($storageConfig));
 		$this->service->expects($this->never())
 			->method('addStorage');
 		$this->service->expects($this->never())
@@ -86,7 +69,7 @@ class UserStoragesControllerTest extends StoragesControllerTest {
 
 		$response = $this->controller->create(
 			'mount',
-			$backendClass,
+			'\OC\Files\Storage\SMB',
 			array(),
 			[],
 			[],
@@ -99,7 +82,7 @@ class UserStoragesControllerTest extends StoragesControllerTest {
 		$response = $this->controller->update(
 			1,
 			'mount',
-			$backendClass,
+			'\OC\Files\Storage\SMB',
 			array(),
 			[],
 			[],