litellm/scripts/health_check/health_check_client.py

457 lines
17 KiB
Python

#!/usr/bin/env python3
"""
LiteLLM Health Check Client
A sentinel health check tool that tests all configured models on a LiteLLM proxy.
This script:
- Can read models from YAML config file or fetch from proxy API
- Sends a simple test request to each model concurrently
- Reports health status for each model
- Supports both chat/completion and embedding models
"""
import asyncio
import json
import os
import sys
import time
from typing import Dict, List, Optional, Tuple
import httpx
import yaml
# Default prompt for health checks - exactly 100k characters
# Generate a repeating pattern to reach exactly 100,000 characters
_base_text = "This is a health check test prompt for LiteLLM proxy. "
_repeat_count = (100000 // len(_base_text)) + 1
_DEFAULT_COMPLETION_PROMPT = (_base_text * _repeat_count)[:100000]
# Default embedding text - also exactly 100k characters
_embedding_base_text = "This is a test for vectorization. "
_embedding_repeat_count = (100000 // len(_embedding_base_text)) + 1
_DEFAULT_EMBEDDING_TEXT = (_embedding_base_text * _embedding_repeat_count)[:100000]
class LiteLLMHealthCheckClient:
"""Client for health checking LiteLLM proxy models."""
def __init__(
self,
base_url: str,
api_key: str,
timeout: int = 120, # Match Go implementation's 120s timeout
completion_prompt: str = _DEFAULT_COMPLETION_PROMPT, # Default ~100k chars
embedding_text: str = _DEFAULT_EMBEDDING_TEXT, # Default ~100k chars
custom_auth_header: Optional[str] = None,
):
"""
Initialize the health check client.
Args:
base_url: Base URL of the LiteLLM proxy (e.g., https://litellm.example.com)
api_key: API key for authentication
timeout: Request timeout in seconds (default: 120, matching Go implementation)
completion_prompt: Test prompt for chat/completion models
embedding_text: Test text for embedding models
custom_auth_header: Optional custom header name for authentication (e.g., "x-requester-service").
If provided, uses this header instead of standard "Authorization" header.
"""
self.base_url = base_url.rstrip("/")
self.api_key = api_key
self.timeout = timeout
self.completion_prompt = completion_prompt
self.embedding_text = embedding_text
# Debug: Print prompt/text lengths
print(
f"DEBUG: Completion prompt length: {len(self.completion_prompt)} characters",
file=sys.stderr,
)
print(
f"DEBUG: Embedding text length: {len(self.embedding_text)} characters",
file=sys.stderr,
)
# Support custom auth header for proxies with custom authentication
# Handle both None and empty string
if custom_auth_header and custom_auth_header.strip():
custom_auth_header = custom_auth_header.strip()
self.headers = {
custom_auth_header: f"Bearer {api_key}",
"Content-Type": "application/json",
}
print(f"Using custom auth header: {custom_auth_header}", file=sys.stderr)
else:
self.headers = {
"Authorization": f"Bearer {api_key}",
"Content-Type": "application/json",
}
print("Using standard Authorization header", file=sys.stderr)
def load_models_from_yaml(self, yaml_path: str) -> List[Dict]:
"""
Load models from a YAML config file (similar to Go implementation).
Args:
yaml_path: Path to the YAML config file
Returns:
List of model dictionaries with 'id' and 'mode' keys
"""
try:
with open(yaml_path, "r") as f:
config = yaml.safe_load(f)
model_list = config.get("model_list", [])
models = []
for entry in model_list:
model_name = entry.get("model_name", "")
litellm_params = entry.get("litellm_params", {})
model_info = litellm_params.get("model_info", {})
mode = model_info.get("mode", "")
# Use model_name as the ID (this is what gets sent to the API)
models.append(
{
"id": model_name,
"mode": mode.lower() if mode else "",
"provider": model_info.get("provider", ""),
}
)
return models
except Exception as e:
print(
f"Error loading models from YAML file {yaml_path}: {e}", file=sys.stderr
)
return []
async def fetch_models(self, client: httpx.AsyncClient) -> List[Dict]:
"""
Fetch all available models from the proxy API.
Returns:
List of model dictionaries with 'id' and 'mode' keys
"""
try:
# Try /v1/models first (OpenAI-compatible endpoint)
response = await client.get(
f"{self.base_url}/v1/models",
headers=self.headers,
timeout=self.timeout,
)
response.raise_for_status()
data = response.json()
models_data = data.get("data", [])
models = []
for m in models_data:
models.append({"id": m["id"], "mode": "", "provider": ""})
return models
except Exception as e:
print(f"Error fetching models from /v1/models: {e}", file=sys.stderr)
# Fallback to /model/info endpoint which has more details
try:
response = await client.get(
f"{self.base_url}/model/info",
headers=self.headers,
timeout=self.timeout,
)
response.raise_for_status()
data = response.json()
if isinstance(data, dict) and "data" in data:
models_data = data["data"]
elif isinstance(data, list):
models_data = data
else:
models_data = []
models = []
for m in models_data:
model_info = m.get("model_info", {})
mode = model_info.get("mode", "")
models.append(
{
"id": m.get("model_name", m.get("id", "unknown")),
"mode": mode.lower() if mode else "",
"provider": model_info.get("provider", ""),
}
)
return models
except Exception as e2:
print(f"Error fetching models from /model/info: {e2}", file=sys.stderr)
return []
async def check_model_health(
self, client: httpx.AsyncClient, model: Dict
) -> Tuple[str, Dict]:
"""
Check health of a single model by sending a test request.
Args:
client: HTTP client
model: Model dictionary with 'id' and 'mode' keys
Returns:
Tuple of (model_id, result_dict)
"""
model_id = model["id"]
mode = model.get("mode", "")
start_time = time.time()
result = {
"model": model_id,
"healthy": False,
"error": None,
"response_time_ms": None,
"mode": mode,
}
try:
# Determine if this is an embedding model
# Check mode first (from config), then fall back to name-based detection
is_embedding = mode == "embedding" or any(
keyword in model_id.lower()
for keyword in ["embedding", "embed", "text-embedding"]
)
if is_embedding:
# Test embedding endpoint (matching Go implementation)
embedding_text_length = len(self.embedding_text)
print(
f"DEBUG: Sending embedding text of length {embedding_text_length} chars to model {model_id}",
file=sys.stderr,
)
embedding_response = await client.post(
f"{self.base_url}/v1/embeddings",
headers=self.headers,
json={
"model": model_id,
"input": self.embedding_text,
},
timeout=self.timeout,
)
embedding_response.raise_for_status()
embedding_data = embedding_response.json()
dimensions = 0
if "data" in embedding_data and len(embedding_data["data"]) > 0:
dimensions = len(embedding_data["data"][0].get("embedding", []))
result["healthy"] = True
result["mode"] = "embedding"
result["dimensions"] = dimensions
else:
# Test chat completion endpoint (matching Go implementation)
prompt_length = len(self.completion_prompt)
print(
f"DEBUG: Sending prompt of length {prompt_length} chars to model {model_id}",
file=sys.stderr,
)
completion_response = await client.post(
f"{self.base_url}/v1/chat/completions",
headers=self.headers,
json={
"model": model_id,
"messages": [
{"role": "user", "content": self.completion_prompt}
],
"max_tokens": 10, # Minimal tokens for health check
},
timeout=self.timeout,
)
completion_response.raise_for_status()
completion_data = completion_response.json()
response_text = ""
if "choices" in completion_data and len(completion_data["choices"]) > 0:
response_text = (
completion_data["choices"][0]
.get("message", {})
.get("content", "")
)
result["healthy"] = True
result["mode"] = "chat"
result["response_text"] = response_text[:100] # Truncate for display
elapsed_ms = (time.time() - start_time) * 1000
result["response_time_ms"] = round(elapsed_ms, 2)
except httpx.HTTPStatusError as e:
result["error"] = f"HTTP {e.response.status_code}: {e.response.text[:200]}"
except httpx.TimeoutException:
result["error"] = f"Request timeout after {self.timeout}s"
except Exception as e:
result["error"] = str(e)[:200]
return model_id, result
async def run_health_checks(
self,
models: Optional[List[Dict]] = None,
models_only: Optional[List[str]] = None,
) -> Dict[str, Dict]:
"""
Run health checks on all models concurrently.
Args:
models: Optional list of models to check. If None, fetches from proxy.
models_only: Optional list of model IDs to check. If set, only these
models are health-checked (must exist in the models list).
Returns:
Dictionary mapping model_id to health check result
"""
async with httpx.AsyncClient() as client:
if models is None:
models = await self.fetch_models(client)
if not models:
print("No models found to health check", file=sys.stderr)
return {}
if models_only:
allowlist = {m.strip() for m in models_only if m and m.strip()}
models = [m for m in models if m.get("id") in allowlist]
print(
f"Filtering to only check {len(models)} models: {', '.join(sorted(allowlist))}",
file=sys.stderr,
)
if not models:
print(
"No models matched LITELLM_MODELS_ONLY filter",
file=sys.stderr,
)
return {}
print(f"Running health checks on {len(models)} models...", file=sys.stderr)
# Run all health checks concurrently
tasks = [self.check_model_health(client, model) for model in models]
results_list = await asyncio.gather(*tasks, return_exceptions=True)
# Convert to dictionary format
results = {}
for result in results_list:
if isinstance(result, Exception):
print(f"Exception in health check task: {result}", file=sys.stderr)
continue
# Type narrowing: after checking it's not an Exception, it's a Tuple
if isinstance(result, tuple) and len(result) == 2:
model_id, result_dict = result
results[model_id] = result_dict
return results
def print_results(self, results: Dict[str, Dict], json_output: bool = False):
"""
Print health check results.
Args:
results: Dictionary of health check results
json_output: If True, output as JSON
"""
if json_output:
print(json.dumps(results, indent=2))
return
healthy_count = sum(1 for r in results.values() if r.get("healthy"))
unhealthy_count = len(results) - healthy_count
# Print detailed results for each model (matching Go output format)
print(f"\n{'='*60}", file=sys.stderr)
print(f"Starting health check queries\n", file=sys.stderr)
for model_id, result in results.items():
if result.get("healthy"):
if result.get("mode") == "embedding":
dimensions = result.get("dimensions", 0)
print(
f"---- {model_id} ----\n✅ Success. "
f"Generated embedding vector with {dimensions} dimensions.\n\n",
file=sys.stderr,
)
else:
response_text = result.get("response_text", "")
print(
f"---- {model_id} ----\n✅ Success. "
f"Response:\n{response_text}\n\n",
file=sys.stderr,
)
else:
error = result.get("error", "Unknown error")
print(f"---- {model_id} ----\n❌ ERROR: {error}\n\n", file=sys.stderr)
print(f"{'='*60}", file=sys.stderr)
print(f"Health Check Summary", file=sys.stderr)
print(f"{'='*60}", file=sys.stderr)
print(f"Total models: {len(results)}", file=sys.stderr)
print(f"Healthy: {healthy_count}", file=sys.stderr)
print(f"Unhealthy: {unhealthy_count}", file=sys.stderr)
print(f"{'='*60}\n", file=sys.stderr)
# Exit with non-zero code if any models are unhealthy
if unhealthy_count > 0:
sys.exit(1)
else:
sys.exit(0)
async def main():
"""Main entry point."""
base_url = os.environ.get("LITELLM_BASE_URL", "http://localhost:4000")
api_key = os.environ.get("LITELLM_API_KEY", "sk-1234")
yaml_path = os.environ.get("LITELLM_MODELS_YAML")
custom_auth_header = os.environ.get(
"LITELLM_CUSTOM_AUTH_HEADER"
) # e.g., "x-requester-service"
# Debug: Print custom auth header value if set
if custom_auth_header:
print(f"Custom auth header from env: '{custom_auth_header}'", file=sys.stderr)
if not base_url:
print("Error: LITELLM_BASE_URL environment variable not set", file=sys.stderr)
sys.exit(1)
if not api_key:
print("Error: LITELLM_API_KEY environment variable not set", file=sys.stderr)
sys.exit(1)
timeout = int(os.environ.get("LITELLM_TIMEOUT", "120")) # Match Go's 120s default
completion_prompt = os.environ.get(
"LITELLM_COMPLETION_PROMPT", _DEFAULT_COMPLETION_PROMPT
)
embedding_text = os.environ.get("LITELLM_EMBEDDING_TEXT", _DEFAULT_EMBEDDING_TEXT)
json_output = os.environ.get("LITELLM_JSON_OUTPUT", "").lower() == "true"
# Optional: only health-check these model IDs (comma-separated). E.g.:
# LITELLM_MODELS_ONLY=claude-3.7-sonnet,claude-3.5-sonnet,claude-4.5-haiku
models_only_raw = os.environ.get("LITELLM_MODELS_ONLY", "")
models_only = [m.strip() for m in models_only_raw.split(",") if m.strip()] or None
client = LiteLLMHealthCheckClient(
base_url=base_url,
api_key=api_key,
timeout=timeout,
completion_prompt=completion_prompt,
embedding_text=embedding_text,
custom_auth_header=custom_auth_header,
)
# Load models from YAML if provided, otherwise fetch from API
models = None
if yaml_path:
models = client.load_models_from_yaml(yaml_path)
if models:
print(
f"Successfully loaded {len(models)} models from {yaml_path}",
file=sys.stderr,
)
results = await client.run_health_checks(models=models, models_only=models_only)
client.print_results(results, json_output=json_output)
if __name__ == "__main__":
asyncio.run(main())