Add debugging helpers to test_state_restore (#86)

See this issue for context:
    #93

.github/workflows/ci.yaml

@@ -97,6 +97,12 @@ jobs:
         run: |
           . venv/bin/activate
           make test
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v3
+        if: ${{ failure() }}
+        with:
+          name: backup
+          path: backupNethsm.bin
       - name: upload coverage
         uses: codecov/codecov-action@v3
         with:

tests/test_nethsm_system.py

@@ -16,7 +16,7 @@
     update,
 )
 
-from nethsm import NetHSM
+from nethsm import NetHSM, NetHSMError
 from nethsm.backup import Backup, EncryptedBackup
 
 """######################### Preparation for the Tests #########################
@@ -104,13 +104,27 @@ def test_state_restore(nethsm: NetHSM) -> None:
     system_time = datetime.datetime.now(datetime.timezone.utc)
     assert nethsm.get_state().value == "Unprovisioned"
 
-    try:
-        with open(C.FILENAME_BACKUP, "rb") as f:
-            nethsm.restore(f, C.BACKUP_PASSPHRASE, system_time)
-            nethsm.unlock(C.UNLOCK_PASSPHRASE)
-    except OSError as e:
-        print(e, type(e))
-        assert False
+    # We repeat the restore call to debug a problem with the restore endpoint in the CI.
+    # See this issue for more information:
+    # https://github.com/Nitrokey/nethsm-sdk-py/issues/93
+
+    successful_try = None
+    last_exception = None
+    for i in range(10):
+        try:
+            with open(C.FILENAME_BACKUP, "rb") as f:
+                nethsm.restore(f, C.BACKUP_PASSPHRASE, system_time)
+            successful_try = i
+        except NetHSMError as e:
+            last_exception = e
+            continue
+
+    if successful_try != 0:
+        print(f"successful try: {successful_try}")
+        assert last_exception
+        raise last_exception
+
+    nethsm.unlock(C.UNLOCK_PASSPHRASE)
 
     assert nethsm.list_keys() == [C.KEY_ID_GENERATED]