From 4c611c42e0cd9c40bdbcce784354b17a1f9f09dd Mon Sep 17 00:00:00 2001
From: James Panayis <james.panayis@ukaea.uk>
Date: Tue, 1 Sep 2026 14:13:33 +0100
Subject: [PATCH 1/2] Add regression tests for upload stream retries

Cover direct and tuple-form multipart POST files, along with file-like PUT request bodies
---
 tests/unit/test_request.py | 65 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 tests/unit/test_request.py

diff --git a/tests/unit/test_request.py b/tests/unit/test_request.py
new file mode 100644
index 00000000..019513b5
--- /dev/null
+++ b/tests/unit/test_request.py
@@ -0,0 +1,65 @@
+import io
+
+import pytest
+from tenacity import wait_none
+
+from simvue.api import request
+
+_PAYLOAD = b"stable-file-contents"
+
+
+class _Response:
+    def __init__(self, status_code: int) -> None:
+        self.status_code = status_code
+
+
+@pytest.mark.local
+@pytest.mark.parametrize("tuple_form", (False, True), ids=("file-object", "tuple"))
+def test_post_retry_rewinds_file_stream(mocker, tuple_form: bool) -> None:
+    payloads = []
+    stream = io.BytesIO(_PAYLOAD)
+    file_value = ("artifact.bin", stream) if tuple_form else stream
+
+    def fake_post(*args, **kwargs):
+        file = kwargs["files"]["file"]
+        file = file[1] if isinstance(file, tuple) else file
+        payloads.append(file.read())
+        return _Response(503 if len(payloads) == 1 else 200)
+
+    mocker.patch.object(request.requests, "post", side_effect=fake_post)
+
+    response = request.post.retry_with(wait=wait_none())(
+        "https://example.invalid",
+        headers={},
+        params={},
+        data={},
+        is_json=False,
+        files={"file": file_value},
+        timeout=1,
+    )
+
+    assert response.status_code == 200
+    assert payloads == [_PAYLOAD, _PAYLOAD]
+
+
+@pytest.mark.local
+def test_put_retry_rewinds_data_stream(mocker) -> None:
+    payloads = []
+    stream = io.BytesIO(_PAYLOAD)
+
+    def fake_put(*args, **kwargs):
+        payloads.append(kwargs["data"].read())
+        return _Response(503 if len(payloads) == 1 else 200)
+
+    mocker.patch.object(request.requests, "put", side_effect=fake_put)
+
+    response = request.put.retry_with(wait=wait_none())(
+        "https://example.invalid",
+        headers={},
+        data=stream,
+        is_json=False,
+        timeout=1,
+    )
+
+    assert response.status_code == 200
+    assert payloads == [_PAYLOAD, _PAYLOAD]

From 20e17360d5df19759f0d87da02ba82edc5371622 Mon Sep 17 00:00:00 2001
From: James Panayis <james.panayis@ukaea.uk>
Date: Tue, 1 Sep 2026 14:14:48 +0100
Subject: [PATCH 2/2] Rewind upload streams before retrying

Rewind multipart POST files and file-like PUT bodies before Tenacity retries the request

Fixes #1002
---
 simvue/api/request.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/simvue/api/request.py b/simvue/api/request.py
index 89ab9555..a4514a09 100644
--- a/simvue/api/request.py
+++ b/simvue/api/request.py
@@ -14,6 +14,7 @@
 
 import requests
 from tenacity import (
+    RetryCallState,
     retry,
     retry_if_exception_type,
     stop_after_attempt,
@@ -46,6 +47,17 @@ class RetryableHTTPError(Exception):
     pass
 
 
+def _rewind_request_streams(retry_state: RetryCallState) -> None:
+    """Rewind file-like request bodies before retrying."""
+    files = retry_state.kwargs.get("files") or {}
+    streams = (*files.values(), retry_state.kwargs.get("data"))
+
+    for value in streams:
+        stream = value[1] if isinstance(value, tuple) else value
+        if callable(seek := getattr(stream, "seek", None)):
+            seek(0)
+
+
 @retry(
     wait=wait_exponential(multiplier=RETRY_MULTIPLIER, min=RETRY_MIN, max=RETRY_MAX),
     stop=stop_after_attempt(RETRY_STOP),
@@ -56,6 +68,7 @@ class RetryableHTTPError(Exception):
             requests.exceptions.ConnectionError,
         ),
     ),
+    before_sleep=_rewind_request_streams,
     reraise=True,
 )
 def post(
@@ -138,6 +151,7 @@ def post(
         ),
     ),
     stop=stop_after_attempt(RETRY_STOP),
+    before_sleep=_rewind_request_streams,
     reraise=True,
 )
 def put(