Gemini API Key Rotator for LlamaIndex

This utility monkey-patches google.auth.api_key.Credentials to rotate multiple Google API keys, useful with LlamaIndex to manage Gemini API request limits.

How to Use

1. Install the package: run this in command prompt pip install gemini-rotator.
2. Import and Patch: Before initializing your Gemini LLM, call the patch function with your API keys. The script modifies the Google authentication library at runtime. When patch is called:
   • It extends the Credentials class to cycle through your provided API keys.

patch(api_keys, api_main=None)

• api_keys: A list of your Google API key strings.
• api_main: (Optional, but Recommended) An API key from api_keys. Rotation only occurs if the default key passed to LlamaIndex or generativeai.configure() matches api_main. This prevents interference with other Google services using different keys. If None, keys rotate on every use (use with caution as it might affect other Google clients).

restore()

Call restore() to revert the monkey-patching and return the google.auth.api_key.Credentials class to its original state.

Example with LlamaIndex

# Assuming the rotator script is saved as gemini_key_rotator.py
from gemini_key_rotator import patch
from llama_index.llms.gemini import Gemini
from llama_index.core.base.llms.types import ChatMessage

# --- Configuration ---
MY_GEMINI_API_KEYS = [
    "YOUR_API_KEY_1", # Replace
    "YOUR_API_KEY_2", # Replace
    "YOUR_API_KEY_3", # Replace
]

MAIN_API_KEY = MY_GEMINI_API_KEYS[0] 
# Monkey patch
patch(MY_GEMINI_API_KEYS, MAIN_API_KEY)

llm = Gemini(model="gemini-2.0-flash", api_key=MAIN_API_KEY) # Initialize LlamaIndex with the main key

messages = [ChatMessage(content="Hello Gemini", role="user")] # Example messages
response = llm.chat(messages=messages) # Send message to Gemini

print(response.message.content) # Print the response

The patch will take care of rotating the API keys for you. The Gemini class will use the main key for initialization, and the rotation will happen automatically when making requests.

Important Notes

• api_main: Using api_main is strongly advised to ensure rotation only affects the intended Gemini client.
• Get API Keys: Obtain your API keys from the Google Cloud Console under "Credentials". You should have Gemini API enabled in your project and its limited to one api key per project. You can create multiple projects to get more keys.
• Risks: Abusing the api may lead to account suspension. Use responsibly and ensure compliance with Google's API usage policies.
• Use Cases: This is not for production use. It's a temporary solution for testing that requires slightly more thant gemini rate limits to effectively test and benchmark.

Disclaimer

Use at your own risk. Comply with Google's API terms.