feat(guardrails): send an empty attachments list when a step has no files [AL-611]

packages/uipath-platform/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "uipath-platform"
-version = "0.2.35"
+version = "0.2.36"
 description = "HTTP client library for programmatic access to UiPath Platform"
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.11"

packages/uipath-platform/src/uipath/platform/guardrails/_guardrails_service.py

@@ -119,7 +119,9 @@ def evaluate_guardrail(
         Args:
             input_data: The text or structured data to validate. Dictionaries will be converted to a string before validation.
             guardrail: A guardrail instance used for validation.
-            attachments: Files attached to the run that the guardrail may inspect.
+            attachments: Files the guardrail may inspect. ``None`` omits the field, so
+                the backend checks only the text. An empty list is sent as ``[]``,
+                meaning files apply but there are none to inspect.
             termination_mode: ``FAIL_FAST`` stops scanning at the first violation;
                 ``EVALUATE_ALL`` or ``None`` scans everything.
 
@@ -141,7 +143,7 @@ def evaluate_guardrail(
                     "BYO (Bring Your Own) guardrails require byo_validator_name."
                 )
             payload["byoValidatorName"] = guardrail.byo_validator_name
-        if attachments:
+        if attachments is not None:
             payload["attachments"] = [a.model_dump(by_alias=True) for a in attachments]
         if termination_mode is not None:
             payload["terminationMode"] = termination_mode.value

packages/uipath-platform/tests/services/test_guardrails_service.py

@@ -975,14 +975,15 @@ def test_attachments_key_is_absent_when_not_supplied(
 
         assert "attachments" not in json.loads(httpx_mock.get_requests()[0].content)
 
-    def test_attachments_key_is_absent_when_empty_list(
+    def test_empty_attachments_list_is_sent_as_empty_list(
         self,
         httpx_mock: HTTPXMock,
         service: GuardrailsService,
         base_url: str,
         org: str,
         tenant: str,
     ) -> None:
+        """An empty list tells the backend files apply but none were found."""
         httpx_mock.add_response(
             url=f"{base_url}{org}{tenant}{_VALIDATE_PATH}",
             status_code=200,
@@ -991,7 +992,8 @@ def test_attachments_key_is_absent_when_empty_list(
 
         service.evaluate_guardrail("x", _judge_guardrail(), attachments=[])
 
-        assert "attachments" not in json.loads(httpx_mock.get_requests()[0].content)
+        body = json.loads(httpx_mock.get_requests()[0].content)
+        assert body["attachments"] == []
 
     def test_attachment_round_trips_the_wire_shape(self) -> None:
         """The camelCase body the API emits parses back into the model unchanged."""
@@ -1126,6 +1128,27 @@ def test_folder_header_absent_without_attachments_even_if_configured(
         request = httpx_mock.get_requests()[0]
         assert "x-uipath-folderkey" not in request.headers
 
+    def test_folder_header_absent_with_empty_attachments_even_if_configured(
+        self,
+        httpx_mock: HTTPXMock,
+        service: GuardrailsService,
+        base_url: str,
+        org: str,
+        tenant: str,
+        monkeypatch: pytest.MonkeyPatch,
+    ) -> None:
+        monkeypatch.setenv("UIPATH_FOLDER_KEY", "folder-key-123")
+        httpx_mock.add_response(
+            url=f"{base_url}{org}{tenant}{_VALIDATE_PATH}",
+            status_code=200,
+            json={"result": "PASSED", "details": ""},
+        )
+
+        service.evaluate_guardrail("x", _judge_guardrail(), attachments=[])
+
+        request = httpx_mock.get_requests()[0]
+        assert "x-uipath-folderkey" not in request.headers
+
 
 class TestGuardrailAttachmentTiming:
     """Attachments still get the longer, file-fetching-aware timeout."""
@@ -1170,6 +1193,26 @@ def test_evaluate_guardrail_keeps_default_timeout_without_attachments(
         timeout = httpx_mock.get_requests()[0].extensions["timeout"]
         assert timeout["read"] != 60.0
 
+    def test_evaluate_guardrail_keeps_default_timeout_with_empty_attachments(
+        self,
+        httpx_mock: HTTPXMock,
+        service: GuardrailsService,
+        base_url: str,
+        org: str,
+        tenant: str,
+    ) -> None:
+        """No file is fetched for an empty list, so it needs no longer timeout."""
+        httpx_mock.add_response(
+            url=f"{base_url}{org}{tenant}{_VALIDATE_PATH}",
+            status_code=200,
+            json={"result": "PASSED", "details": ""},
+        )
+
+        service.evaluate_guardrail("x", _judge_guardrail(), attachments=[])
+
+        timeout = httpx_mock.get_requests()[0].extensions["timeout"]
+        assert timeout["read"] != 60.0
+
 
 class TestGuardrailFlaggedAttachmentIds:
     """evaluate_guardrail parses the flagged attachment ids from the response."""