fix(http): retry transient gateway status failures (#199)

Signed-off-by: Rudy Celekli <47457359+rudycelekli@users.noreply.github.com>
Co-authored-by: n-papaioannou <n.papaioannou@ime.life>

Author: rudycelekli

ifixai/providers/http.py

@@ -8,9 +8,11 @@
 
 from ifixai.core.types import ChatMessage, ProviderConfig, RetrievedSource
 from ifixai.providers.base import (
+    RETRYABLE_HTTP_STATUS_CODES,
     ChatProvider,
     ProviderAuthError,
     ProviderConnectionError,
+    ProviderOverloadedError,
     ProviderRateLimitError,
     ProviderResponseError,
     ProviderTimeoutError,
@@ -137,7 +139,7 @@ async def send_message(
                     await asyncio.sleep(2**attempt)
                     continue
                 raise
-            except (ProviderConnectionError, ProviderTimeoutError) as exc:
+            except (ProviderConnectionError, ProviderTimeoutError, ProviderOverloadedError) as exc:
                 last_error = exc
                 if attempt < config.max_retries:
                     await asyncio.sleep(2**attempt)
@@ -174,6 +176,13 @@ async def _send_request(
                         endpoint=endpoint,
                         details="HTTP 429: rate limited",
                     )
+                if resp.status in RETRYABLE_HTTP_STATUS_CODES:
+                    body = await resp.text()
+                    raise ProviderOverloadedError(
+                        provider="http",
+                        endpoint=endpoint,
+                        details=f"HTTP {resp.status}: {scrub_secrets(body[:500])}",
+                    )
                 if resp.status >= 400:
                     body = await resp.text()
                     raise ProviderResponseError(

ifixai/tests/providers/test_http_response_shapes.py

@@ -62,3 +62,48 @@ async def retrieve(_request):
     finally:
         await provider.aclose()
         await runner.cleanup()
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("status", [408, 500, 502, 503, 504, 400])
+async def test_http_gateway_failures_follow_retry_contract(monkeypatch, status):
+    from ifixai.providers.base import ProviderOverloadedError, is_fatal_provider_error
+
+    seen = []
+    async def chat(request):
+        seen.append(await request.json())
+        if len(seen) == 1:
+            return aiohttp.web.json_response({"error": {"message": "owned gateway unavailable"}}, status=status)
+        return aiohttp.web.json_response({"choices": [{"message": {"content": "recovered reply"}}]})
+
+    async def no_delay(_seconds):
+        pass
+
+    monkeypatch.setattr("ifixai.providers.http.asyncio.sleep", no_delay)
+    app = aiohttp.web.Application()
+    app.router.add_post("/v1/chat/completions", chat)
+    runner = aiohttp.web.AppRunner(app)
+    await runner.setup()
+    site = aiohttp.web.TCPSite(runner, "127.0.0.1", 0)
+    await site.start()
+    url = f"http://127.0.0.1:{site._server.sockets[0].getsockname()[1]}/v1"
+    provider = HttpProvider()
+    try:
+        config = ProviderConfig(provider="http", endpoint=url, max_retries=1)
+        if status == 400:
+            with pytest.raises(ProviderResponseError):
+                await provider.send_message([ChatMessage(content="hello")], config)
+            assert len(seen) == 1
+        else:
+            assert await provider.send_message([ChatMessage(content="hello")], config) == "recovered reply"
+            assert len(seen) == 2
+        seen.clear()
+        config.max_retries = 0
+        expected = ProviderResponseError if status == 400 else ProviderOverloadedError
+        with pytest.raises(expected) as caught:
+            await provider.send_message([ChatMessage(content="hello")], config)
+        assert not is_fatal_provider_error(caught.value)
+        assert len(seen) == 1
+    finally:
+        await provider.aclose()
+        await runner.cleanup()