π LightRAG: Simple and Fast Retrieval-Augmented Generation
This repository hosts the code of LightRAG. The structure of this code is based on [nano-graphrag](https://github.com/gusye1234/nano-graphrag).
![LightRAG Diagram](https://i-blog.csdnimg.cn/direct/b2aaf634151b4706892693ffb43d9093.png)
π News
[x] [2024.11.19]π―π’We have added a detailed blog link introducing LightRAG on LearnOpenCV. Many thanks to the blog author!
Use the below Python snippet (in a script) to initialize LightRAG and perform queries:
import os
from lightrag import LightRAG, QueryParam
from lightrag.llm import gpt_4o_mini_complete, gpt_4o_complete
#########
# Uncomment the below two lines if running in a jupyter notebook to handle the async nature of rag.insert()
# import nest_asyncio
# nest_asyncio.apply()
#########
WORKING_DIR = "./dickens"
if not os.path.exists(WORKING_DIR):
os.mkdir(WORKING_DIR)
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=gpt_4o_mini_complete # Use gpt_4o_mini_complete LLM model
# llm_model_func=gpt_4o_complete # Optionally, use a stronger model
)
with open("./book.txt") as f:
rag.insert(f.read())
# Perform naive search
print(rag.query("What are the top themes in this story?", param=QueryParam(mode="naive")))
# Perform local search
print(rag.query("What are the top themes in this story?", param=QueryParam(mode="local")))
# Perform global search
print(rag.query("What are the top themes in this story?", param=QueryParam(mode="global")))
# Perform hybrid search
print(rag.query("What are the top themes in this story?", param=QueryParam(mode="hybrid")))
Using Open AI-like APIs
* LightRAG also supports Open AI-like chat/embeddings APIs:
```python
async def llm_model_func(
prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
return await openai_complete_if_cache(
"solar-mini",
prompt,
system_prompt=system_prompt,
history_messages=history_messages,
api_key=os.getenv("UPSTAGE_API_KEY"),
base_url="https://api.upstage.ai/v1/solar",
**kwargs
)
async def embedding_func(texts: list[str]) -> np.ndarray:
return await openai_embedding(
texts,
model="solar-embedding-1-large-query",
api_key=os.getenv("UPSTAGE_API_KEY"),
base_url="https://api.upstage.ai/v1/solar"
)
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=llm_model_func,
embedding_func=EmbeddingFunc(
embedding_dim=4096,
max_token_size=8192,
func=embedding_func
)
)
```
Using Hugging Face Models
* If you want to use Hugging Face models, you only need to set LightRAG as follows:
```python
from lightrag.llm import hf_model_complete, hf_embedding
from transformers import AutoModel, AutoTokenizer
from lightrag.utils import EmbeddingFunc
# Initialize LightRAG with Hugging Face model
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=hf_model_complete, # Use Hugging Face model for text generation
llm_model_name='meta-llama/Llama-3.1-8B-Instruct', # Model name from Hugging Face
# Use Hugging Face embedding function
embedding_func=EmbeddingFunc(
embedding_dim=384,
max_token_size=5000,
func=lambda texts: hf_embedding(
texts,
tokenizer=AutoTokenizer.from_pretrained("sentence-transformers/all-MiniLM-L6-v2"),
embed_model=AutoModel.from_pretrained("sentence-transformers/all-MiniLM-L6-v2")
)
),
)
```
Using Ollama Models
### Overview
If you want to use Ollama models, you need to pull model you plan to use and embedding model, for example `nomic-embed-text`.
Then you only need to set LightRAG as follows:
```python
from lightrag.llm import ollama_model_complete, ollama_embedding
from lightrag.utils import EmbeddingFunc
# Initialize LightRAG with Ollama model
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=ollama_model_complete, # Use Ollama model for text generation
llm_model_name='your_model_name', # Your model name
# Use Ollama embedding function
embedding_func=EmbeddingFunc(
embedding_dim=768,
max_token_size=8192,
func=lambda texts: ollama_embedding(
texts,
embed_model="nomic-embed-text"
)
),
)
```
### Using Neo4J for Storage
* For production level scenarios you will most likely want to leverage an enterprise solution
* for KG storage. Running Neo4J in Docker is recommended for seamless local testing.
* See: https://hub.docker.com/_/neo4j
```python
export NEO4J_URI="neo4j://localhost:7687"
export NEO4J_USERNAME="neo4j"
export NEO4J_PASSWORD="password"
When you launch the project be sure to override the default KG: NetworkS
by specifying kg="Neo4JStorage".
# Note: Default settings use NetworkX
#Initialize LightRAG with Neo4J implementation.
WORKING_DIR = "./local_neo4jWorkDir"
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=gpt_4o_mini_complete, # Use gpt_4o_mini_complete LLM model
kg="Neo4JStorage", #<-----------override KG default
log_level="DEBUG" #<-----------override log_level default
)
```
see test_neo4j.py for a working example.
### Increasing context size
In order for LightRAG to work context should be at least 32k tokens. By default Ollama models have context size of 8k. You can achieve this using one of two ways:
#### Increasing the `num_ctx` parameter in Modelfile.
1. Pull the model:
```bash
ollama pull qwen2
```
2. Display the model file:
```bash
ollama show --modelfile qwen2 > Modelfile
```
3. Edit the Modelfile by adding the following line:
```bash
PARAMETER num_ctx 32768
```
4. Create the modified model:
```bash
ollama create -f Modelfile qwen2m
```
#### Setup `num_ctx` via Ollama API.
Tiy can use `llm_model_kwargs` param to configure ollama:
```python
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=ollama_model_complete, # Use Ollama model for text generation
llm_model_name='your_model_name', # Your model name
llm_model_kwargs={"options": {"num_ctx": 32768}},
# Use Ollama embedding function
embedding_func=EmbeddingFunc(
embedding_dim=768,
max_token_size=8192,
func=lambda texts: ollama_embedding(
texts,
embed_model="nomic-embed-text"
)
),
)
```
#### Fully functional example
There fully functional example `examples/lightrag_ollama_demo.py` that utilizes `gemma2:2b` model, runs only 4 requests in parallel and set context size to 32k.
#### Low RAM GPUs
In order to run this experiment on low RAM GPU you should select small model and tune context window (increasing context increase memory consumption). For example, running this ollama example on repurposed mining GPU with 6Gb of RAM required to set context size to 26k while using `gemma2:2b`. It was able to find 197 entities and 19 relations on `book.txt`.
Query Param
class QueryParam:
mode: Literal["local", "global", "hybrid", "naive"] = "global"
only_need_context: bool = False
response_type: str = "Multiple Paragraphs"
# Number of top-k items to retrieve; corresponds to entities in "local" mode and relationships in "global" mode.
top_k: int = 60
# Number of tokens for the original chunks.
max_token_for_text_unit: int = 4000
# Number of tokens for the relationship descriptions
max_token_for_global_context: int = 4000
# Number of tokens for the entity descriptions
max_token_for_local_context: int = 4000
Batch Insert
# Batch Insert: Insert multiple texts at once
rag.insert(["TEXT1", "TEXT2",...])
Incremental Insert
# Incremental Insert: Insert new documents into an existing LightRAG instance
rag = LightRAG(
working_dir=WORKING_DIR,
llm_model_func=llm_model_func,
embedding_func=EmbeddingFunc(
embedding_dim=embedding_dimension,
max_token_size=8192,
func=embedding_func,
),
)
with open("./newText.txt") as f:
rag.insert(f.read())
Graph visualization with html
* The following code can be found in `examples/graph_visual_with_html.py`
```python
import networkx as nx
from pyvis.network import Network
# Load the GraphML file
G = nx.read_graphml('./dickens/graph_chunk_entity_relation.graphml')
# Create a Pyvis network
net = Network(notebook=True)
# Convert NetworkX graph to Pyvis network
net.from_nx(G)
# Save and display the network
net.show('knowledge_graph.html')
```
Graph visualization with Neo4j
* The following code can be found in `examples/graph_visual_with_neo4j.py`
```python
import os
import json
from lightrag.utils import xml_to_json
from neo4j import GraphDatabase
# Constants
WORKING_DIR = "./dickens"
BATCH_SIZE_NODES = 500
BATCH_SIZE_EDGES = 100
# Neo4j connection credentials
NEO4J_URI = "bolt://localhost:7687"
NEO4J_USERNAME = "neo4j"
NEO4J_PASSWORD = "your_password"
def convert_xml_to_json(xml_path, output_path):
"""Converts XML file to JSON and saves the output."""
if not os.path.exists(xml_path):
print(f"Error: File not found - {xml_path}")
return None
json_data = xml_to_json(xml_path)
if json_data:
with open(output_path, 'w', encoding='utf-8') as f:
json.dump(json_data, f, ensure_ascii=False, indent=2)
print(f"JSON file created: {output_path}")
return json_data
else:
print("Failed to create JSON data")
return None
def process_in_batches(tx, query, data, batch_size):
"""Process data in batches and execute the given query."""
for i in range(0, len(data), batch_size):
batch = data[i:i + batch_size]
tx.run(query, {"nodes": batch} if "nodes" in query else {"edges": batch})
def main():
# Paths
xml_file = os.path.join(WORKING_DIR, 'graph_chunk_entity_relation.graphml')
json_file = os.path.join(WORKING_DIR, 'graph_data.json')
# Convert XML to JSON
json_data = convert_xml_to_json(xml_file, json_file)
if json_data is None:
return
# Load nodes and edges
nodes = json_data.get('nodes', [])
edges = json_data.get('edges', [])
# Neo4j queries
create_nodes_query = """
UNWIND $nodes AS node
MERGE (e:Entity {id: node.id})
SET e.entity_type = node.entity_type,
e.description = node.description,
e.source_id = node.source_id,
e.displayName = node.id
REMOVE e:Entity
WITH e, node
CALL apoc.create.addLabels(e, [node.entity_type]) YIELD node AS labeledNode
RETURN count(*)
"""
create_edges_query = """
UNWIND $edges AS edge
MATCH (source {id: edge.source})
MATCH (target {id: edge.target})
WITH source, target, edge,
CASE
WHEN edge.keywords CONTAINS 'lead' THEN 'lead'
WHEN edge.keywords CONTAINS 'participate' THEN 'participate'
WHEN edge.keywords CONTAINS 'uses' THEN 'uses'
WHEN edge.keywords CONTAINS 'located' THEN 'located'
WHEN edge.keywords CONTAINS 'occurs' THEN 'occurs'
ELSE REPLACE(SPLIT(edge.keywords, ',')[0], '\"', '')
END AS relType
CALL apoc.create.relationship(source, relType, {
weight: edge.weight,
description: edge.description,
keywords: edge.keywords,
source_id: edge.source_id
}, target) YIELD rel
RETURN count(*)
"""
set_displayname_and_labels_query = """
MATCH (n)
SET n.displayName = n.id
WITH n
CALL apoc.create.setLabels(n, [n.entity_type]) YIELD node
RETURN count(*)
"""
# Create a Neo4j driver
driver = GraphDatabase.driver(NEO4J_URI, auth=(NEO4J_USERNAME, NEO4J_PASSWORD))
try:
# Execute queries in batches
with driver.session() as session:
# Insert nodes in batches
session.execute_write(process_in_batches, create_nodes_query, nodes, BATCH_SIZE_NODES)
# Insert edges in batches
session.execute_write(process_in_batches, create_edges_query, edges, BATCH_SIZE_EDGES)
# Set displayName and labels
session.run(set_displayname_and_labels_query)
except Exception as e:
print(f"Error occurred: {e}")
finally:
driver.close()
if __name__ == "__main__":
main()
```
API Server Implementation
LightRAG also provides a FastAPI-based server implementation for RESTful API access to RAG operations. This allows you to run LightRAG as a service and interact with it through HTTP requests.
Setting up the API Server
Click to expand setup instructions
1. First, ensure you have the required dependencies:
```bash
pip install fastapi uvicorn pydantic
```
2. Set up your environment variables:
```bash
export RAG_DIR="your_index_directory" # Optional: Defaults to "index_default"
export OPENAI_BASE_URL="Your OpenAI API base URL" # Optional: Defaults to "https://api.openai.com/v1"
export OPENAI_API_KEY="Your OpenAI API key" # Required
export LLM_MODEL="Your LLM model" # Optional: Defaults to "gpt-4o-mini"
export EMBEDDING_MODEL="Your embedding model" # Optional: Defaults to "text-embedding-3-large"
```
3. Run the API server:
```bash
python examples/lightrag_api_openai_compatible_demo.py
```
The server will start on `http://0.0.0.0:8020`.
API Endpoints
The API server provides the following endpoints:
1. Query Endpoint
Click to view Query endpoint details
- **URL:** `/query`
- **Method:** POST
- **Body:**
```json
{
"query": "Your question here",
"mode": "hybrid", // Can be "naive", "local", "global", or "hybrid"
"only_need_context": true // Optional: Defaults to false, if true, only the referenced context will be returned, otherwise the llm answer will be returned
}
```
- **Example:**
```bash
curl -X POST "http://127.0.0.1:8020/query" \
-H "Content-Type: application/json" \
-d '{"query": "What are the main themes?", "mode": "hybrid"}'
```
2. Insert Text Endpoint
Click to view Insert Text endpoint details
- **URL:** `/insert`
- **Method:** POST
- **Body:**
```json
{
"text": "Your text content here"
}
```
- **Example:**
```bash
curl -X POST "http://127.0.0.1:8020/insert" \
-H "Content-Type: application/json" \
-d '{"text": "Content to be inserted into RAG"}'
```
Click to view Health Check endpoint details
- **URL:** `/health`
- **Method:** GET
- **Example:**
```bash
curl -X GET "http://127.0.0.1:8020/health"
```
Configuration
The API server can be configured using environment variables:
RAG_DIR: Directory for storing the RAG index (default: "index_default")
API keys and base URLs should be configured in the code for your specific LLM and embedding model providers
Error Handling
Click to view error handling details
The API includes comprehensive error handling:
- File not found errors (404)
- Processing errors (500)
- Supports multiple file encodings (UTF-8 and GBK)
LightRAG uses the following prompt to generate high-level queries, with the corresponding code in example/generate_query.py.
Prompt
```python
Given the following description of a dataset:
{description}
Please identify 5 potential users who would engage with this dataset. For each user, list 5 tasks they would perform with this dataset. Then, for each (user, task) combination, generate 5 questions that require a high-level understanding of the entire dataset.
Output the results in the following structure:
- User 1: [user description]
- Task 1: [task description]
- Question 1:
- Question 2:
- Question 3:
- Question 4:
- Question 5:
- Task 2: [task description]
...
- Task 5: [task description]
- User 2: [user description]
...
- User 5: [user description]
...
```
Batch Eval
To evaluate the performance of two RAG systems on high-level queries, LightRAG uses the following prompt, with the specific code available in example/batch_eval.py.
Prompt
```python
---Role---
You are an expert tasked with evaluating two answers to the same question based on three criteria: **Comprehensiveness**, **Diversity**, and **Empowerment**.
---Goal---
You will evaluate two answers to the same question based on three criteria: **Comprehensiveness**, **Diversity**, and **Empowerment**.
- **Comprehensiveness**: How much detail does the answer provide to cover all aspects and details of the question?
- **Diversity**: How varied and rich is the answer in providing different perspectives and insights on the question?
- **Empowerment**: How well does the answer help the reader understand and make informed judgments about the topic?
For each criterion, choose the better answer (either Answer 1 or Answer 2) and explain why. Then, select an overall winner based on these three categories.
Here is the question:
{query}
Here are the two answers:
**Answer 1:**
{answer1}
**Answer 2:**
{answer2}
Evaluate both answers using the three criteria listed above and provide detailed explanations for each criterion.
Output your evaluation in the following JSON format:
{{
"Comprehensiveness": {{
"Winner": "[Answer 1 or Answer 2]",
"Explanation": "[Provide explanation here]"
}},
"Empowerment": {{
"Winner": "[Answer 1 or Answer 2]",
"Explanation": "[Provide explanation here]"
}},
"Overall Winner": {{
"Winner": "[Answer 1 or Answer 2]",
"Explanation": "[Summarize why this answer is the overall winner based on the three criteria]"
}}
}}
```
Overall Performance Table
Agriculture
CS
Legal
Mix
NaiveRAG
LightRAG
NaiveRAG
LightRAG
NaiveRAG
LightRAG
NaiveRAG
LightRAG
Comprehensiveness
32.4%
67.6%
38.4%
61.6%
16.4%
83.6%
38.8%
61.2%
Diversity
23.6%
76.4%
38.0%
62.0%
13.6%
86.4%
32.4%
67.6%
Empowerment
32.4%
67.6%
38.8%
61.2%
16.4%
83.6%
42.8%
57.2%
Overall
32.4%
67.6%
38.8%
61.2%
15.2%
84.8%
40.0%
60.0%
RQ-RAG
LightRAG
RQ-RAG
LightRAG
RQ-RAG
LightRAG
RQ-RAG
LightRAG
Comprehensiveness
31.6%
68.4%
38.8%
61.2%
15.2%
84.8%
39.2%
60.8%
Diversity
29.2%
70.8%
39.2%
60.8%
11.6%
88.4%
30.8%
69.2%
Empowerment
31.6%
68.4%
36.4%
63.6%
15.2%
84.8%
42.4%
57.6%
Overall
32.4%
67.6%
38.0%
62.0%
14.4%
85.6%
40.0%
60.0%
HyDE
LightRAG
HyDE
LightRAG
HyDE
LightRAG
HyDE
LightRAG
Comprehensiveness
26.0%
74.0%
41.6%
58.4%
26.8%
73.2%
40.4%
59.6%
Diversity
24.0%
76.0%
38.8%
61.2%
20.0%
80.0%
32.4%
67.6%
Empowerment
25.2%
74.8%
40.8%
59.2%
26.0%
74.0%
46.0%
54.0%
Overall
24.8%
75.2%
41.6%
58.4%
26.4%
73.6%
42.4%
57.6%
GraphRAG
LightRAG
GraphRAG
LightRAG
GraphRAG
LightRAG
GraphRAG
LightRAG
Comprehensiveness
45.6%
54.4%
48.4%
51.6%
48.4%
51.6%
50.4%
49.6%
Diversity
22.8%
77.2%
40.8%
59.2%
26.4%
73.6%
36.0%
64.0%
Empowerment
41.2%
58.8%
45.2%
54.8%
43.6%
56.4%
50.8%
49.2%
Overall
45.2%
54.8%
48.0%
52.0%
47.2%
52.8%
50.4%
49.6%
Reproduce
All the code can be found in the ./reproduce directory.
Step-0 Extract Unique Contexts
First, we need to extract unique contexts in the datasets.
Code
```python
def extract_unique_contexts(input_directory, output_directory):
os.makedirs(output_directory, exist_ok=True)
jsonl_files = glob.glob(os.path.join(input_directory, '*.jsonl'))
print(f"Found {len(jsonl_files)} JSONL files.")
for file_path in jsonl_files:
filename = os.path.basename(file_path)
name, ext = os.path.splitext(filename)
output_filename = f"{name}_unique_contexts.json"
output_path = os.path.join(output_directory, output_filename)
unique_contexts_dict = {}
print(f"Processing file: {filename}")
try:
with open(file_path, 'r', encoding='utf-8') as infile:
for line_number, line in enumerate(infile, start=1):
line = line.strip()
if not line:
continue
try:
json_obj = json.loads(line)
context = json_obj.get('context')
if context and context not in unique_contexts_dict:
unique_contexts_dict[context] = None
except json.JSONDecodeError as e:
print(f"JSON decoding error in file {filename} at line {line_number}: {e}")
except FileNotFoundError:
print(f"File not found: {filename}")
continue
except Exception as e:
print(f"An error occurred while processing file {filename}: {e}")
continue
unique_contexts_list = list(unique_contexts_dict.keys())
print(f"There are {len(unique_contexts_list)} unique `context` entries in the file {filename}.")
try:
with open(output_path, 'w', encoding='utf-8') as outfile:
json.dump(unique_contexts_list, outfile, ensure_ascii=False, indent=4)
print(f"Unique `context` entries have been saved to: {output_filename}")
except Exception as e:
print(f"An error occurred while saving to the file {output_filename}: {e}")
print("All files have been processed.")
```
Step-1 Insert Contexts
For the extracted contexts, we insert them into the LightRAG system.
Code
```python
def insert_text(rag, file_path):
with open(file_path, mode='r') as f:
unique_contexts = json.load(f)
retries = 0
max_retries = 3
while retries < max_retries:
try:
rag.insert(unique_contexts)
break
except Exception as e:
retries += 1
print(f"Insertion failed, retrying ({retries}/{max_retries}), error: {e}")
time.sleep(10)
if retries == max_retries:
print("Insertion failed after exceeding the maximum number of retries")
```
Step-2 Generate Queries
We extract tokens from the first and the second half of each context in the dataset, then combine them as dataset descriptions to generate queries.
@article{guo2024lightrag,
title={LightRAG: Simple and Fast Retrieval-Augmented Generation},
author={Zirui Guo and Lianghao Xia and Yanhua Yu and Tu Ao and Chao Huang},
year={2024},
eprint={2410.05779},
archivePrefix={arXiv},
primaryClass={cs.IR}
}