fix(openai_compatible): omit rerank authorization without an API key (#206)

Co-authored-by: WH-2099 <wh2099@pm.me>

src/dify_plugin/interfaces/model/openai_compatible/rerank.py

@@ -66,10 +66,9 @@ class OAICompatRerankModel(RerankModel):
             raise CredentialsValidateFailedError(msg)
 
         url = server_url
-        headers = {
-            "Authorization": f"Bearer {credentials.get('api_key')}",
-            "Content-Type": "application/json",
-        }
+        headers = {"Content-Type": "application/json"}
+        if api_key := credentials.get("api_key"):
+            headers["Authorization"] = f"Bearer {api_key}"
 
         # Open question: truncate docs before llama.cpp-compatible requests?
 

tests/interfaces/model/openai_compatible/test_rerank.py

@@ -0,0 +1,51 @@
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from dify_plugin.interfaces.model.openai_compatible.rerank import (
+    OAICompatRerankModel,
+)
+
+
+@pytest.mark.parametrize(
+    ("credentials", "expected_headers"),
+    [
+        (
+            {"endpoint_url": "https://example.com/v1"},
+            {"Content-Type": "application/json"},
+        ),
+        (
+            {"endpoint_url": "https://example.com/v1", "api_key": None},
+            {"Content-Type": "application/json"},
+        ),
+        (
+            {"endpoint_url": "https://example.com/v1", "api_key": ""},
+            {"Content-Type": "application/json"},
+        ),
+        (
+            {"endpoint_url": "https://example.com/v1", "api_key": str(123)},
+            {
+                "Authorization": "Bearer 123",
+                "Content-Type": "application/json",
+            },
+        ),
+    ],
+)
+def test_invoke_only_sends_authorization_with_api_key(
+    credentials: dict, expected_headers: dict[str, str]
+) -> None:
+    response = MagicMock()
+    response.json.return_value = {"results": [{"index": 0, "relevance_score": 1.0}]}
+
+    with patch(
+        "dify_plugin.interfaces.model.openai_compatible.rerank.post",
+        return_value=response,
+    ) as post:
+        OAICompatRerankModel([]).invoke(
+            model="model",
+            credentials=credentials,
+            query="query",
+            docs=["document"],
+        )
+
+    assert post.call_args.kwargs["headers"] == expected_headers