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Using RetrieveChat Powered by PGVector for Retrieve Augmented Code Generation and Question Answering#

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AG2 offers conversable agents powered by LLM, tool or human, which can be used to perform tasks collectively via automated chat. This framework allows tool use and human participation through multi-agent conversation. Please find documentation about this feature here.

RetrieveChat is a conversational system for retrieval-augmented code generation and question answering. In this notebook, we demonstrate how to utilize RetrieveChat to generate code and answer questions based on customized documentations that are not present in the LLM’s training dataset. RetrieveChat uses the AssistantAgent and RetrieveUserProxyAgent, which is similar to the usage of AssistantAgent and UserProxyAgent in other notebooks (e.g., Automated Task Solving with Code Generation, Execution & Debugging). Essentially, RetrieveUserProxyAgent implement a different auto-reply mechanism corresponding to the RetrieveChat prompts.

Table of Contents#

We’ll demonstrate six examples of using RetrieveChat for code generation and question answering:

Requirements

Some extra dependencies are needed for this notebook, which can be installed via pip:

pip install autogen[retrievechat-pgvector] flaml[automl]

For more information, please refer to the installation guide.

Ensure you have a PGVector instance.

If not, a test version can quickly be deployed using Docker.

docker-compose.yml

version: '3.9'

services:
  pgvector:
    image: pgvector/pgvector:pg16
    shm_size: 128mb
    restart: unless-stopped
    ports:
      - "5432:5432"
    environment:
      POSTGRES_USER: <postgres-user>
      POSTGRES_PASSWORD: <postgres-password>
      POSTGRES_DB: <postgres-database>
    volumes:
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql

Create init.sql file

CREATE EXTENSION IF NOT EXISTS vector;

Set your API Endpoint#

The config_list_from_json function loads a list of configurations from an environment variable or a json file.

import os

import psycopg
from sentence_transformers import SentenceTransformer

import autogen
from autogen import AssistantAgent
from autogen.agentchat.contrib.retrieve_user_proxy_agent import RetrieveUserProxyAgent

# Accepted file formats for that can be stored in
# a vector database instance
from autogen.retrieve_utils import TEXT_FORMATS

config_list = autogen.config_list_from_json(
    "OAI_CONFIG_LIST",
    file_location=".",
)
assert len(config_list) > 0
print("models to use: ", [config_list[i]["model"] for i in range(len(config_list))])

Tip

Learn more about configuring LLMs for agents here.

Construct agents for RetrieveChat#

We start by initializing the AssistantAgent and RetrieveUserProxyAgent. The system message needs to be set to “You are a helpful assistant.” for AssistantAgent. The detailed instructions are given in the user message. Later we will use the RetrieveUserProxyAgent.message_generator to combine the instructions and a retrieval augmented generation task for an initial prompt to be sent to the LLM assistant.

print("Accepted file formats for `docs_path`:")
print(TEXT_FORMATS)
# 1. create an AssistantAgent instance named "assistant"
assistant = AssistantAgent(
    name="assistant",
    system_message="You are a helpful assistant. You must always reply with some form of text.",
    llm_config={
        "timeout": 600,
        "cache_seed": 42,
        "config_list": config_list,
    },
)

# Optionally create psycopg conn object
# conn = psycopg.connect(conninfo="postgresql://postgres:postgres@localhost:5432/postgres", autocommit=True)

# Optionally create embedding function object
sentence_transformer_ef = SentenceTransformer("all-distilroberta-v1").encode

# 2. create the RetrieveUserProxyAgent instance named "ragproxyagent"
# Refer to https://docs.ag2.ai/docs/reference/agentchat/contrib/retrieve_user_proxy_agent
# and https://docs.ag2.ai/docs/reference/agentchat/contrib/vectordb/pgvectordb
# for more information on the RetrieveUserProxyAgent and PGVectorDB
ragproxyagent = RetrieveUserProxyAgent(
    name="ragproxyagent",
    human_input_mode="NEVER",
    max_consecutive_auto_reply=1,
    retrieve_config={
        "task": "code",
        "docs_path": [
            "https://raw.githubusercontent.com/microsoft/FLAML/main/website/docs/Examples/Integrate%20-%20Spark.md",
            "https://raw.githubusercontent.com/microsoft/FLAML/main/website/docs/Research.md",
        ],
        "chunk_token_size": 2000,
        "model": config_list[0]["model"],
        "vector_db": "pgvector",  # PGVector database
        "collection_name": "flaml_collection",
        "db_config": {
            "connection_string": "postgresql://postgres:postgres@localhost:5432/postgres",  # Optional - connect to an external vector database
            # "host": "postgres", # Optional vector database host
            # "port": 5432, # Optional vector database port
            # "dbname": "postgres", # Optional vector database name
            # "username": "postgres", # Optional vector database username
            # "password": "postgres", # Optional vector database password
            # "conn": conn, # Optional - conn object to connect to database
        },
        "get_or_create": True,  # set to False if you don't want to reuse an existing collection
        "overwrite": True,  # set to True if you want to overwrite an existing collection
        "embedding_function": sentence_transformer_ef,  # If left out SentenceTransformer("all-MiniLM-L6-v2").encode will be used
    },
    code_execution_config=False,  # set to False if you don't want to execute the code
)

Example 1#

Back to top

Use RetrieveChat to help generate sample code and automatically run the code and fix errors if there is any.

Problem: Which API should I use if I want to use FLAML for a classification task and I want to train the model in 30 seconds. Use spark to parallel the training. Force cancel jobs if time limit is reached.

# reset the assistant. Always reset the assistant before starting a new conversation.
assistant.reset()

# given a problem, we use the ragproxyagent to generate a prompt to be sent to the assistant as the initial message.
# the assistant receives the message and generates a response. The response will be sent back to the ragproxyagent for processing.
# The conversation continues until the termination condition is met, in RetrieveChat, the termination condition when no human-in-loop is no code block detected.
# With human-in-loop, the conversation will continue until the user says "exit".
code_problem = "How can I use FLAML to perform a classification task and use spark to do parallel training. Train for 30 seconds and force cancel jobs if time limit is reached."
chat_result = ragproxyagent.initiate_chat(
    assistant, message=ragproxyagent.message_generator, problem=code_problem, search_string="spark"
)

Example 2#

Back to top

Use RetrieveChat to answer a question that is not related to code generation.

Problem: Who is the author of FLAML?

# reset the assistant. Always reset the assistant before starting a new conversation.
assistant.reset()

# Optionally create psycopg conn object
conn = psycopg.connect(conninfo="postgresql://postgres:postgres@localhost:5432/postgres", autocommit=True)

ragproxyagent = RetrieveUserProxyAgent(
    name="ragproxyagent",
    human_input_mode="NEVER",
    max_consecutive_auto_reply=1,
    retrieve_config={
        "task": "code",
        "docs_path": [
            "https://raw.githubusercontent.com/microsoft/FLAML/main/website/docs/Examples/Integrate%20-%20Spark.md",
            "https://raw.githubusercontent.com/microsoft/FLAML/main/website/docs/Research.md",
            os.path.join(os.path.abspath(""), "..", "website", "docs"),
        ],
        "custom_text_types": ["non-existent-type"],
        "chunk_token_size": 2000,
        "model": config_list[0]["model"],
        "vector_db": "pgvector",  # PGVector database
        "collection_name": "flaml_collection",
        "db_config": {
            # "connection_string": "postgresql://postgres:postgres@localhost:5432/postgres",  # Optional - connect to an external vector database
            # "host": "postgres", # Optional vector database host
            # "port": 5432, # Optional vector database port
            # "dbname": "postgres", # Optional vector database name
            # "username": "postgres", # Optional vector database username
            # "password": "postgres", # Optional vector database password
            "conn": conn,  # Optional - conn object to connect to database
        },
        "get_or_create": True,  # set to False if you don't want to reuse an existing collection
        "overwrite": True,  # set to True if you want to overwrite an existing collection
    },
    code_execution_config=False,  # set to False if you don't want to execute the code
)

qa_problem = "Who is the author of FLAML?"
chat_result = ragproxyagent.initiate_chat(assistant, message=ragproxyagent.message_generator, problem=qa_problem)