Add objectExists to objectstore interface

Signed-off-by: Robin Appelman <robin@icewind.nl>

lib/private/Files/ObjectStore/Azure.php

@@ -115,4 +115,17 @@ class Azure implements IObjectStore {
 	public function deleteObject($urn) {
 		$this->getBlobClient()->deleteBlob($this->containerName, $urn);
 	}
+
+	public function objectExists($urn) {
+		try {
+			$this->getBlobClient()->getBlobMetadata($this->containerName, $urn);
+			return true;
+		} catch (ServiceException $e) {
+			if ($e->getCode() === 404) {
+				return false;
+			} else {
+				throw $e;
+			}
+		}
+	}
 }

lib/private/Files/ObjectStore/S3ObjectTrait.php

@@ -90,4 +90,8 @@ trait S3ObjectTrait {
 			'Key' => $urn
 		]);
 	}
+
+	public function objectExists($urn) {
+		return $this->getConnection()->doesObjectExist($this->bucket, $urn);
+	}
 }

lib/private/Files/ObjectStore/StorageObjectStore.php

@@ -89,4 +89,7 @@ class StorageObjectStore implements IObjectStore {
 		$this->storage->unlink($urn);
 	}
 
+	public function objectExists($urn) {
+		return $this->storage->file_exists($urn);
+	}
 }

lib/private/Files/ObjectStore/Swift.php

@@ -128,4 +128,7 @@ class Swift implements IObjectStore {
 		$this->getContainer()->delete();
 	}
 
+	public function objectExists($urn) {
+		return $this->getContainer()->objectExists($urn);
+	}
 }

lib/public/Files/ObjectStore/IObjectStore.php

@@ -63,4 +63,13 @@ interface IObjectStore {
 	 * @since 7.0.0
 	 */
 	public function deleteObject($urn);
+
+	/**
+	 * Check if an object exists in the object store
+	 *
+	 * @param string $urn
+	 * @return bool
+	 * @since 16.0.0
+	 */
+	public function objectExists($urn);
 }

tests/lib/Files/ObjectStore/ObjectStoreTest.php

@@ -94,4 +94,19 @@ abstract class ObjectStoreTest extends TestCase {
 			$this->assertEquals(1, 1);
 		}
 	}
+
+	public function testExists() {
+		$stream = $this->stringToStream('foobar');
+
+		$instance = $this->getInstance();
+		$this->assertFalse($instance->objectExists('2'));
+
+		$instance->writeObject('2', $stream);
+
+		$this->assertTrue($instance->objectExists('2'));
+
+		$instance->deleteObject('2');
+
+		$this->assertFalse($instance->objectExists('2'));
+	}
 }