LightRAG/lightrag/evaluation/eval_rag_quality.py
anouarbm 1ad0bf82f9 feat: add RAGAS evaluation framework for RAG quality assessment
This contribution adds a comprehensive evaluation system using the RAGAS
framework to assess LightRAG's retrieval and generation quality.

Features:
- RAGEvaluator class with four key metrics:
  * Faithfulness: Answer accuracy vs context
  * Answer Relevance: Query-response alignment
  * Context Recall: Retrieval completeness
  * Context Precision: Retrieved context quality
- HTTP API integration for live system testing
- JSON and CSV report generation
- Configurable test datasets
- Complete documentation with examples
- Sample test dataset included

Changes:
- Added lightrag/evaluation/eval_rag_quality.py (RAGAS evaluator implementation)
- Added lightrag/evaluation/README.md (comprehensive documentation)
- Added lightrag/evaluation/__init__.py (package initialization)
- Updated pyproject.toml with optional 'evaluation' dependencies
- Updated .gitignore to exclude evaluation results directory

Installation:
pip install lightrag-hku[evaluation]

Dependencies:
- ragas>=0.3.7
- datasets>=4.3.0
- httpx>=0.28.1
- pytest>=8.4.2
- pytest-asyncio>=1.2.0
2025-11-01 21:36:39 +01:00

394 lines
14 KiB
Python

#!/usr/bin/env python3
"""
RAGAS Evaluation Script for Portfolio RAG System
Evaluates RAG response quality using RAGAS metrics:
- Faithfulness: Is the answer factually accurate based on context?
- Answer Relevance: Is the answer relevant to the question?
- Context Recall: Is all relevant information retrieved?
- Context Precision: Is retrieved context clean without noise?
Usage:
python lightrag/evaluation/eval_rag_quality.py
python lightrag/evaluation/eval_rag_quality.py http://localhost:8000
python lightrag/evaluation/eval_rag_quality.py http://your-rag-server.com:8000
Results are saved to: lightrag/evaluation/results/
- results_YYYYMMDD_HHMMSS.csv (CSV export for analysis)
- results_YYYYMMDD_HHMMSS.json (Full results with details)
"""
import json
import asyncio
import time
import csv
from pathlib import Path
from datetime import datetime
from typing import Any, Dict, List
import sys
import httpx
import os
from dotenv import load_dotenv
# Add parent directory to path
sys.path.insert(0, str(Path(__file__).parent.parent.parent))
# Load .env from project root
project_root = Path(__file__).parent.parent.parent
load_dotenv(project_root / ".env")
# Setup OpenAI API key (required for RAGAS evaluation)
# Use LLM_BINDING_API_KEY if OPENAI_API_KEY is not set
if "OPENAI_API_KEY" not in os.environ:
if "LLM_BINDING_API_KEY" in os.environ:
os.environ["OPENAI_API_KEY"] = os.environ["LLM_BINDING_API_KEY"]
else:
os.environ["OPENAI_API_KEY"] = input("Enter your OpenAI API key: ")
try:
from ragas import evaluate
from ragas.metrics import (
faithfulness,
answer_relevancy,
context_recall,
context_precision,
)
from datasets import Dataset
except ImportError as e:
print(f"❌ RAGAS import error: {e}")
print(" Install with: pip install ragas datasets")
sys.exit(1)
class RAGEvaluator:
"""Evaluate RAG system quality using RAGAS metrics"""
def __init__(self, test_dataset_path: str = None, rag_api_url: str = None):
"""
Initialize evaluator with test dataset
Args:
test_dataset_path: Path to test dataset JSON file
rag_api_url: Base URL of LightRAG API (e.g., http://localhost:8000)
If None, will try to read from environment or use default
"""
if test_dataset_path is None:
test_dataset_path = Path(__file__).parent / "test_dataset.json"
if rag_api_url is None:
rag_api_url = os.getenv("LIGHTRAG_API_URL", "http://localhost:8000")
self.test_dataset_path = Path(test_dataset_path)
self.rag_api_url = rag_api_url.rstrip("/") # Remove trailing slash
self.results_dir = Path(__file__).parent / "results"
self.results_dir.mkdir(exist_ok=True)
# Load test dataset
self.test_cases = self._load_test_dataset()
def _load_test_dataset(self) -> List[Dict[str, str]]:
"""Load test cases from JSON file"""
if not self.test_dataset_path.exists():
raise FileNotFoundError(f"Test dataset not found: {self.test_dataset_path}")
with open(self.test_dataset_path) as f:
data = json.load(f)
return data.get("test_cases", [])
async def generate_rag_response(
self,
question: str,
context: str = None, # Not used - actual context comes from LightRAG
) -> Dict[str, str]:
"""
Generate RAG response by calling LightRAG API
Calls the actual LightRAG /query endpoint instead of using mock data.
Args:
question: The user query
context: Ignored (for compatibility), actual context from LightRAG
Returns:
Dict with 'answer' and 'context' keys
Raises:
Exception: If LightRAG API is unavailable
"""
try:
async with httpx.AsyncClient(timeout=60.0) as client:
# Prepare request to LightRAG API
payload = {
"query": question,
"mode": "mix", # Recommended: combines local & global
"include_references": True,
"response_type": "Multiple Paragraphs",
"top_k": 10,
}
# Call LightRAG /query endpoint
response = await client.post(
f"{self.rag_api_url}/query",
json=payload,
)
if response.status_code != 200:
raise Exception(
f"LightRAG API error {response.status_code}: {response.text}"
)
result = response.json()
return {
"answer": result.get("response", "No response generated"),
"context": json.dumps(result.get("references", []))
if result.get("references")
else "",
}
except httpx.ConnectError:
raise Exception(
f"❌ Cannot connect to LightRAG API at {self.rag_api_url}\n"
f" Make sure LightRAG server is running:\n"
f" python -m lightrag.api.lightrag_server"
)
except Exception as e:
raise Exception(f"Error calling LightRAG API: {str(e)}")
async def evaluate_responses(self) -> List[Dict[str, Any]]:
"""
Evaluate all test cases and return metrics
Returns:
List of evaluation results with metrics
"""
print("\n" + "=" * 70)
print("🚀 Starting RAGAS Evaluation of Portfolio RAG System")
print("=" * 70 + "\n")
results = []
for idx, test_case in enumerate(self.test_cases, 1):
question = test_case["question"]
ground_truth = test_case["ground_truth"]
print(f"[{idx}/{len(self.test_cases)}] Evaluating: {question[:60]}...")
# Generate RAG response by calling actual LightRAG API
rag_response = await self.generate_rag_response(question=question)
# Prepare dataset for RAGAS evaluation
eval_dataset = Dataset.from_dict(
{
"question": [question],
"answer": [rag_response["answer"]],
"contexts": [
[ground_truth]
], # RAGAS expects list of context strings
"ground_truth": [ground_truth],
}
)
# Run RAGAS evaluation
try:
eval_results = evaluate(
dataset=eval_dataset,
metrics=[
faithfulness,
answer_relevancy,
context_recall,
context_precision,
],
)
# Convert to DataFrame (RAGAS v0.3+ API)
df = eval_results.to_pandas()
# Extract scores from first row
scores_row = df.iloc[0]
# Extract scores (RAGAS v0.3+ uses .to_pandas())
result = {
"question": question,
"answer": rag_response["answer"][:200] + "..."
if len(rag_response["answer"]) > 200
else rag_response["answer"],
"ground_truth": ground_truth[:200] + "..."
if len(ground_truth) > 200
else ground_truth,
"project": test_case.get("project_context", "unknown"),
"metrics": {
"faithfulness": float(scores_row.get("faithfulness", 0)),
"answer_relevance": float(
scores_row.get("answer_relevancy", 0)
),
"context_recall": float(scores_row.get("context_recall", 0)),
"context_precision": float(
scores_row.get("context_precision", 0)
),
},
"timestamp": datetime.now().isoformat(),
}
# Calculate RAGAS score (average of all metrics)
metrics = result["metrics"]
ragas_score = sum(metrics.values()) / len(metrics) if metrics else 0
result["ragas_score"] = round(ragas_score, 4)
results.append(result)
# Print metrics
print(f" ✅ Faithfulness: {metrics['faithfulness']:.4f}")
print(f" ✅ Answer Relevance: {metrics['answer_relevance']:.4f}")
print(f" ✅ Context Recall: {metrics['context_recall']:.4f}")
print(f" ✅ Context Precision: {metrics['context_precision']:.4f}")
print(f" 📊 RAGAS Score: {result['ragas_score']:.4f}\n")
except Exception as e:
import traceback
print(f" ❌ Error evaluating: {str(e)}")
print(f" 🔍 Full traceback:\n{traceback.format_exc()}\n")
result = {
"question": question,
"error": str(e),
"metrics": {},
"ragas_score": 0,
"timestamp": datetime.now().isoformat()
}
results.append(result)
return results
def _export_to_csv(self, results: List[Dict[str, Any]]) -> Path:
"""
Export evaluation results to CSV file
Args:
results: List of evaluation results
Returns:
Path to the CSV file
CSV Format:
- question: The test question
- project: Project context
- faithfulness: Faithfulness score (0-1)
- answer_relevance: Answer relevance score (0-1)
- context_recall: Context recall score (0-1)
- context_precision: Context precision score (0-1)
- ragas_score: Overall RAGAS score (0-1)
- timestamp: When evaluation was run
"""
csv_path = self.results_dir / f"results_{datetime.now().strftime('%Y%m%d_%H%M%S')}.csv"
with open(csv_path, "w", newline="", encoding="utf-8") as f:
fieldnames = [
"test_number",
"question",
"project",
"faithfulness",
"answer_relevance",
"context_recall",
"context_precision",
"ragas_score",
"status",
"timestamp",
]
writer = csv.DictWriter(f, fieldnames=fieldnames)
writer.writeheader()
for idx, result in enumerate(results, 1):
metrics = result.get("metrics", {})
writer.writerow({
"test_number": idx,
"question": result.get("question", ""),
"project": result.get("project", "unknown"),
"faithfulness": f"{metrics.get('faithfulness', 0):.4f}",
"answer_relevance": f"{metrics.get('answer_relevance', 0):.4f}",
"context_recall": f"{metrics.get('context_recall', 0):.4f}",
"context_precision": f"{metrics.get('context_precision', 0):.4f}",
"ragas_score": f"{result.get('ragas_score', 0):.4f}",
"status": "success" if metrics else "error",
"timestamp": result.get("timestamp", ""),
})
return csv_path
async def run(self) -> Dict[str, Any]:
"""Run complete evaluation pipeline"""
start_time = time.time()
# Evaluate responses
results = await self.evaluate_responses()
elapsed_time = time.time() - start_time
# Save results
summary = {
"timestamp": datetime.now().isoformat(),
"total_tests": len(results),
"elapsed_time_seconds": round(elapsed_time, 2),
"results": results
}
# Save JSON results
json_path = self.results_dir / f"results_{datetime.now().strftime('%Y%m%d_%H%M%S')}.json"
with open(json_path, "w") as f:
json.dump(summary, f, indent=2)
print(f"✅ JSON results saved to: {json_path}")
# Export to CSV
csv_path = self._export_to_csv(results)
print(f"✅ CSV results saved to: {csv_path}")
# Print summary
print("\n" + "="*70)
print("📊 EVALUATION COMPLETE")
print("="*70)
print(f"Total Tests: {len(results)}")
print(f"Elapsed Time: {elapsed_time:.2f} seconds")
print(f"Results Dir: {self.results_dir.absolute()}")
print("\n📁 Generated Files:")
print(f" • CSV: {csv_path.name}")
print(f" • JSON: {json_path.name}")
print("="*70 + "\n")
return summary
async def main():
"""
Main entry point for RAGAS evaluation
Usage:
python lightrag/evaluation/eval_rag_quality.py
python lightrag/evaluation/eval_rag_quality.py http://localhost:8000
python lightrag/evaluation/eval_rag_quality.py http://your-server.com:8000
"""
try:
# Get RAG API URL from command line or environment
rag_api_url = None
if len(sys.argv) > 1:
rag_api_url = sys.argv[1]
print("\n" + "="*70)
print("🔍 RAGAS Evaluation - Using Real LightRAG API")
print("="*70)
if rag_api_url:
print(f"📡 RAG API URL: {rag_api_url}")
else:
print(f"📡 RAG API URL: http://localhost:8000 (default)")
print("="*70 + "\n")
evaluator = RAGEvaluator(rag_api_url=rag_api_url)
await evaluator.run()
except Exception as e:
print(f"\n❌ Error: {str(e)}\n")
sys.exit(1)
if __name__ == "__main__":
asyncio.run(main())