feat(llm): custom request headers for OpenAI-compatible endpoints via LLM_EXTRA_HEADERS

tests/test_llm_extra_headers.py

@@ -0,0 +1,83 @@
+"""Tests for LLM_EXTRA_HEADERS: custom default headers on OpenAI-compatible endpoints."""
+
+from __future__ import annotations
+
+import json
+from typing import TYPE_CHECKING
+
+import litellm
+import pytest
+from agents.models import _openai_shared
+
+from strix.config import loader
+from strix.config.loader import load_settings
+from strix.config.models import configure_sdk_model_defaults
+
+
+if TYPE_CHECKING:
+    from collections.abc import Iterator
+
+
+_ENV_KEYS = ["STRIX_LLM", "LLM_API_KEY", "LLM_API_BASE", "LLM_EXTRA_HEADERS"]
+
+
+@pytest.fixture(autouse=True)
+def _reset(monkeypatch: pytest.MonkeyPatch) -> Iterator[None]:
+    for key in _ENV_KEYS:
+        monkeypatch.delenv(key, raising=False)
+    monkeypatch.setattr(loader, "_cached", None)
+    monkeypatch.setattr(loader, "_override", None)
+
+    saved_headers = litellm.headers
+    saved_client = _openai_shared.get_default_openai_client()
+    litellm.headers = None
+    try:
+        yield
+    finally:
+        litellm.headers = saved_headers
+        _openai_shared.set_default_openai_client(saved_client)  # type: ignore[arg-type]
+
+
+def test_extra_headers_parsed_from_json_env(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("LLM_EXTRA_HEADERS", json.dumps({"X-A": "1", "X-B": "2"}))
+    settings = load_settings()
+    assert settings.llm.extra_headers == {"X-A": "1", "X-B": "2"}
+
+
+def test_extra_headers_merged_into_litellm_headers(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("STRIX_LLM", "litellm/openai/some-model")
+    monkeypatch.setenv("LLM_API_BASE", "https://gateway.example/v1")
+    monkeypatch.setenv("LLM_API_KEY", "token")
+    headers = {"X-Feature-Key": "svc", "X-Tenant": "acme"}
+    monkeypatch.setenv("LLM_EXTRA_HEADERS", json.dumps(headers))
+
+    configure_sdk_model_defaults(load_settings())
+
+    current: object = litellm.headers
+    assert isinstance(current, dict)
+    assert current["X-Feature-Key"] == "svc"
+    assert current["X-Tenant"] == "acme"
+
+
+def test_extra_headers_applied_to_native_openai_client(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("STRIX_LLM", "openai/some-model")
+    monkeypatch.setenv("LLM_API_BASE", "https://gateway.example/v1")
+    monkeypatch.setenv("LLM_API_KEY", "token")
+    monkeypatch.setenv("LLM_EXTRA_HEADERS", json.dumps({"X-Feature-Key": "svc"}))
+
+    configure_sdk_model_defaults(load_settings())
+
+    client = _openai_shared.get_default_openai_client()
+    assert client is not None
+    assert client.default_headers.get("X-Feature-Key") == "svc"
+    assert str(client.base_url).rstrip("/") == "https://gateway.example/v1"
+
+
+def test_no_extra_headers_leaves_litellm_headers_untouched(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("STRIX_LLM", "openai/some-model")
+    monkeypatch.setenv("LLM_API_BASE", "https://gateway.example/v1")
+    monkeypatch.setenv("LLM_API_KEY", "token")
+
+    configure_sdk_model_defaults(load_settings())
+
+    assert litellm.headers is None