test(backups): more checks regarding tmpdirs and mounting

selfprivacy_api/backup/backuppers/restic_backupper.py

@@ -126,7 +126,9 @@ class ResticBackupper(AbstractBackupper):
                     output,
                 )
 
-    def mount_repo(self, mount_directory):
+    def mount_repo(self, mount_directory: str) -> subprocess.Popen:
+        if not exists(mount_directory):
+            raise FileNotFoundError("no such directory to mount at: ", mount_directory)
         mount_command = self.restic_command("mount", mount_directory)
         mount_command.insert(0, "nohup")
         handle = subprocess.Popen(
@@ -139,7 +141,7 @@ class ResticBackupper(AbstractBackupper):
             raise IOError("failed to mount dir ", mount_directory)
         return handle
 
-    def unmount_repo(self, mount_directory):
+    def unmount_repo(self, mount_directory: str) -> None:
         mount_command = ["umount", "-l", mount_directory]
         with subprocess.Popen(
             mount_command, stdout=subprocess.PIPE, shell=False
@@ -147,10 +149,10 @@ class ResticBackupper(AbstractBackupper):
             output = handle.communicate()[0].decode("utf-8")
             # TODO: check for exit code?
             if "error" in output.lower():
-                return IOError("failed to unmount dir ", mount_directory, ": ", output)
+                raise IOError("failed to unmount dir ", mount_directory, ": ", output)
 
         if not listdir(mount_directory) == []:
-            return IOError("failed to unmount dir ", mount_directory)
+            raise IOError("failed to unmount dir ", mount_directory)
 
     @staticmethod
     def __flatten_list(list_to_flatten):
@@ -363,6 +365,9 @@ class ResticBackupper(AbstractBackupper):
                 self._raw_verified_restore(snapshot_id, target=temp_dir)
                 snapshot_root = temp_dir
             else:  # attempting inplace restore via mount + sync
+                assert exists(
+                    temp_dir
+                )  # paranoid check, TemporaryDirectory is supposedly created
                 self.mount_repo(temp_dir)
                 snapshot_root = join(temp_dir, "ids", snapshot_id)
 

tests/test_graphql/test_backup.py

@@ -8,6 +8,8 @@ from os import urandom
 from datetime import datetime, timedelta, timezone
 from subprocess import Popen
 
+import tempfile
+
 import selfprivacy_api.services as services
 from selfprivacy_api.services import Service, get_all_services
 
@@ -806,3 +808,10 @@ def test_operations_while_locked(backups, dummy_service):
     # check that no locks were left
     Backups.provider().backupper.lock()
     Backups.provider().backupper.unlock()
+
+
+# a paranoid check to weed out problems with tempdirs that are not dependent on us
+def test_tempfile():
+    with tempfile.TemporaryDirectory() as temp:
+        assert path.exists(temp)
+    assert not path.exists(temp)