fix(files): a token made as every session ends goes with them, and a file being shared holds its job

backend/tests/test_folder_links.py

@@ -325,3 +325,73 @@ def test_a_file_whose_bytes_are_gone_is_not_offered(shelf, client, db):
     (Path(settings.files_root) / asset.rel_path).unlink()
     assert _ids(client, token) == [shelf["inside"][1]]
     assert client.get(f"/api/public/watch/{token}/files/{gone}/file").status_code == 404
+
+
+def _meanwhile(work):
+    """Run `work(other_session)` in another thread and session, committed; (thread, outcome)."""
+    import threading
+
+    from app.db import SessionLocal
+
+    outcome: list[object] = []
+
+    def run():
+        other = SessionLocal()
+        try:
+            outcome.append(work(other))
+            other.commit()
+        except Exception as e:  # noqa: BLE001 — the assertion below names what went wrong
+            outcome.append(e)
+        finally:
+            other.close()
+
+    t = threading.Thread(target=run)
+    t.start()
+    return t, outcome
+
+
+def test_two_opens_at_once_count_as_two_views(shelf, db):
+    from app.routes import public
+
+    made = _link(shelf)
+    link = db.get(DownloadLink, made["id"])
+    public._opened(db, link, made["token"])  # this open's count is not committed yet
+    t, outcome = _meanwhile(
+        lambda other: public._opened(other, other.get(DownloadLink, made["id"]), made["token"])
+    )
+    t.join(timeout=1)
+    db.commit()
+    t.join(timeout=10)
+    assert not isinstance(outcome[0], Exception), outcome
+    db.expire_all()
+    assert db.get(DownloadLink, made["id"]).view_count == 2
+
+
+def test_a_file_shared_as_it_is_deleted_takes_its_new_link_with_it(shelf, db):
+    from app.routes import downloads as routes
+
+    job_id = shelf["outside"]
+    routes._shareable_job(db, shelf["user"], job_id)  # held from the check until this commits
+    t, outcome = _meanwhile(lambda other: other.delete(other.get(DownloadJob, job_id)))
+    t.join(timeout=1)
+    assert t.is_alive()  # the delete waits for the link on its way in
+    db.add(DownloadLink(job_id=job_id, token_hash="h" * 64, created_by=shelf["user"].id))
+    db.commit()
+    t.join(timeout=10)
+    assert outcome == [None]
+    assert db.execute(select(DownloadLink.id)).scalars().all() == []
+
+
+def test_a_folder_shared_as_it_is_deleted_takes_its_new_link_with_it(shelf, db):
+    from app.routes import downloads as routes
+
+    fid = shelf["folder"]
+    routes._shareable_folder(db, shelf["user"], fid)  # held from the check until this commits
+    t, outcome = _meanwhile(lambda other: folders.delete_own(other, other.get(FileFolder, fid)))
+    t.join(timeout=1)
+    assert t.is_alive()  # the delete waits for the link on its way in
+    db.add(DownloadLink(folder_id=fid, token_hash="h" * 64, created_by=shelf["user"].id))
+    db.commit()
+    t.join(timeout=10)
+    assert not isinstance(outcome[0], Exception), outcome
+    assert db.execute(select(DownloadLink.id)).scalars().all() == []