feat: improve Gemini client error handling and retry logic

• Add google-api-core dependency
• Add specific exception handling
• Create InvalidResponseError class
• Update retry decorators
• Fix empty response handling

lightrag/llm/gemini.py

@@ -33,18 +33,27 @@ from lightrag.utils import (
 
 import pipmaster as pm
 
-# Install the Google Gemini client on demand
+# Install the Google Gemini client and its dependencies on demand
 if not pm.is_installed("google-genai"):
     pm.install("google-genai")
+if not pm.is_installed("google-api-core"):
+    pm.install("google-api-core")
 
 from google import genai  # type: ignore
 from google.genai import types  # type: ignore
+from google.api_core import exceptions as google_api_exceptions  # type: ignore
 
 DEFAULT_GEMINI_ENDPOINT = "https://generativelanguage.googleapis.com"
 
 LOG = logging.getLogger(__name__)
 
 
+class InvalidResponseError(Exception):
+    """Custom exception class for triggering retry mechanism when Gemini returns empty responses"""
+
+    pass
+
+
 @lru_cache(maxsize=8)
 def _get_gemini_client(
     api_key: str, base_url: str | None, timeout: int | None = None
@@ -176,6 +185,21 @@ def _extract_response_text(
     return ("\n".join(regular_parts), "\n".join(thought_parts))
 
 
+@retry(
+    stop=stop_after_attempt(3),
+    wait=wait_exponential(multiplier=1, min=4, max=60),
+    retry=(
+        retry_if_exception_type(google_api_exceptions.InternalServerError)
+        | retry_if_exception_type(google_api_exceptions.ServiceUnavailable)
+        | retry_if_exception_type(google_api_exceptions.ResourceExhausted)
+        | retry_if_exception_type(google_api_exceptions.GatewayTimeout)
+        | retry_if_exception_type(google_api_exceptions.BadGateway)
+        | retry_if_exception_type(google_api_exceptions.DeadlineExceeded)
+        | retry_if_exception_type(google_api_exceptions.Aborted)
+        | retry_if_exception_type(google_api_exceptions.Unknown)
+        | retry_if_exception_type(InvalidResponseError)
+    ),
+)
 async def gemini_complete_if_cache(
     model: str,
     prompt: str,
@@ -382,7 +406,7 @@ async def gemini_complete_if_cache(
         final_text = regular_text or ""
 
     if not final_text:
-        raise RuntimeError("Gemini response did not contain any text content.")
+        raise InvalidResponseError("Gemini response did not contain any text content.")
 
     if "\\u" in final_text:
         final_text = safe_unicode_decode(final_text.encode("utf-8"))
@@ -434,7 +458,14 @@ async def gemini_model_complete(
     stop=stop_after_attempt(3),
     wait=wait_exponential(multiplier=1, min=4, max=60),
     retry=(
-        retry_if_exception_type(Exception)  # Gemini uses generic exceptions
+        retry_if_exception_type(google_api_exceptions.InternalServerError)
+        | retry_if_exception_type(google_api_exceptions.ServiceUnavailable)
+        | retry_if_exception_type(google_api_exceptions.ResourceExhausted)
+        | retry_if_exception_type(google_api_exceptions.GatewayTimeout)
+        | retry_if_exception_type(google_api_exceptions.BadGateway)
+        | retry_if_exception_type(google_api_exceptions.DeadlineExceeded)
+        | retry_if_exception_type(google_api_exceptions.Aborted)
+        | retry_if_exception_type(google_api_exceptions.Unknown)
     ),
 )
 async def gemini_embed(

pyproject.toml

@@ -24,6 +24,7 @@ dependencies = [
     "aiohttp",
     "configparser",
     "future",
+    "google-api-core>=2.0.0,<3.0.0",
     "google-genai>=1.0.0,<2.0.0",
     "json_repair",
     "nano-vectordb",
@@ -60,6 +61,7 @@ api = [
     "tenacity",
     "tiktoken",
     "xlsxwriter>=3.1.0",
+    "google-api-core>=2.0.0,<3.0.0",
     "google-genai>=1.0.0,<2.0.0",
     # API-specific dependencies
     "aiofiles",
@@ -108,6 +110,7 @@ offline-llm = [
     "aioboto3>=12.0.0,<16.0.0",
     "voyageai>=0.2.0,<1.0.0",
     "llama-index>=0.9.0,<1.0.0",
+    "google-api-core>=2.0.0,<3.0.0",
     "google-genai>=1.0.0,<2.0.0",
 ]
 

requirements-offline-llm.txt

@@ -10,6 +10,7 @@
 # LLM provider dependencies (with version constraints matching pyproject.toml)
 aioboto3>=12.0.0,<16.0.0
 anthropic>=0.18.0,<1.0.0
+google-api-core>=2.0.0,<3.0.0
 google-genai>=1.0.0,<2.0.0
 llama-index>=0.9.0,<1.0.0
 ollama>=0.1.0,<1.0.0