[refactor] make delete_blob() return a deferred

src/leap/soledad/server/_blobs.py

@@ -147,6 +147,7 @@ class FilesystemBlobsBackend(object):
             os.unlink(blob_path + '.flags')
         except Exception:
             pass
+        return defer.succeed(None)
 
     def get_blob_size(self, user, blob_id, namespace=''):
         blob_path = self._get_path(user, blob_id, namespace)
@@ -303,13 +304,17 @@ class BlobsResource(resource.Resource):
     def render_DELETE(self, request):
         logger.info("http put: %s" % request.path)
         user, blob_id, namespace = self._validate(request)
-        try:
-            self._handler.delete_blob(user, blob_id, namespace=namespace)
-            return ''
-        except BlobNotFound:
+
+        def catchBlobNotFound(failure):
+            failure.trap(BlobNotFound)
             request.setResponseCode(404)
             return "Blob doesn't exists: %s" % blob_id
 
+        d = self._handler.delete_blob(user, blob_id, namespace=namespace)
+        d.addCallback(lambda _: request.finish())
+        d.addErrback(catchBlobNotFound)
+        return NOT_DONE_YET
+
     def render_PUT(self, request):
         logger.info("http put: %s" % request.path)
         user, blob_id, namespace = self._validate(request)

src/leap/soledad/server/interfaces.py

@@ -69,6 +69,9 @@ class IBlobsBackend(Interface):
         :type blob_id: str
         :param namespace: An optional namespace for the blob.
         :type namespace: str
+
+        :return: A deferred that fires when the blob has been deleted.
+        :rtype: twisted.internet.defer.Deferred
         """
 
     def get_blob_size(user, blob_id, namespace=''):

tests/blobs/test_fs_backend.py

@@ -170,6 +170,7 @@ class FilesystemBackendTestCase(unittest.TestCase):
 
     @pytest.mark.usefixtures("method_tmpdir")
     @mock.patch('leap.soledad.server._blobs.os.unlink')
+    @defer.inlineCallbacks
     def test_delete_blob(self, unlink_mock):
         backend = _blobs.FilesystemBlobsBackend(blobs_path=self.tempdir)
         # write a blob...
@@ -178,7 +179,7 @@ class FilesystemBackendTestCase(unittest.TestCase):
         with open(path, "w") as f:
             f.write("bl0b")
         # ...and delete it
-        backend.delete_blob('user', 'blob_id')
+        yield backend.delete_blob('user', 'blob_id')
         unlink_mock.assert_any_call(backend._get_path('user',
                                                       'blob_id'))
         unlink_mock.assert_any_call(backend._get_path('user',
@@ -186,6 +187,7 @@ class FilesystemBackendTestCase(unittest.TestCase):
 
     @pytest.mark.usefixtures("method_tmpdir")
     @mock.patch('leap.soledad.server._blobs.os.unlink')
+    @defer.inlineCallbacks
     def test_delete_blob_custom_namespace(self, unlink_mock):
         backend = _blobs.FilesystemBlobsBackend(blobs_path=self.tempdir)
         # write a blob...
@@ -194,7 +196,7 @@ class FilesystemBackendTestCase(unittest.TestCase):
         with open(path, "w") as f:
             f.write("bl0b")
         # ...and delete it
-        backend.delete_blob('user', 'blob_id', namespace='trash')
+        yield backend.delete_blob('user', 'blob_id', namespace='trash')
         unlink_mock.assert_any_call(backend._get_path('user',
                                                       'blob_id',
                                                       'trash'))