llama-stack/llama_stack/distribution/ui/page/playground/rag.py
Ilya Kolchinsky 40f41af2f7
feat: Add a direct (non-agentic) RAG option to the Playground RAG page (#1940)
# What does this PR do?
This PR makes it possible to switch between agentic and non-agentic RAG
when running the respective Playground page.
When non-agentic RAG is selected, user queries are answered by directly
querying the vector DB, augmenting the prompt, and sending the extended
prompt to the model via Inference API.

## Test Plan
- Launch the Playground and go to the RAG page;
- Select the vector DB ID;
- Adjust other configuration parameters if necessary;
- Set the radio button to Agent-based RAG;
- Send a message to the chat;
- The query will be answered by an agent using the knowledge search tool
as indicated by the output;
- Click the 'Clear Chat' button to make it possible to switch modes;
- Send a message to the chat again;
- This time, the query will be answered by the model directly as can be
deduced from the reply.
2025-04-11 10:16:10 -07:00

294 lines
11 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import uuid
import streamlit as st
from llama_stack_client import Agent, AgentEventLogger, RAGDocument
from llama_stack.apis.common.content_types import ToolCallDelta
from llama_stack.distribution.ui.modules.api import llama_stack_api
from llama_stack.distribution.ui.modules.utils import data_url_from_file
def rag_chat_page():
st.title("🦙 RAG")
def reset_agent_and_chat():
st.session_state.clear()
st.cache_resource.clear()
def should_disable_input():
return "displayed_messages" in st.session_state and len(st.session_state.displayed_messages) > 0
with st.sidebar:
# File/Directory Upload Section
st.subheader("Upload Documents", divider=True)
uploaded_files = st.file_uploader(
"Upload file(s) or directory",
accept_multiple_files=True,
type=["txt", "pdf", "doc", "docx"], # Add more file types as needed
)
# Process uploaded files
if uploaded_files:
st.success(f"Successfully uploaded {len(uploaded_files)} files")
# Add memory bank name input field
vector_db_name = st.text_input(
"Document Collection Name",
value="rag_vector_db",
help="Enter a unique identifier for this document collection",
)
if st.button("Create Document Collection"):
documents = [
RAGDocument(
document_id=uploaded_file.name,
content=data_url_from_file(uploaded_file),
)
for i, uploaded_file in enumerate(uploaded_files)
]
providers = llama_stack_api.client.providers.list()
vector_io_provider = None
for x in providers:
if x.api == "vector_io":
vector_io_provider = x.provider_id
llama_stack_api.client.vector_dbs.register(
vector_db_id=vector_db_name, # Use the user-provided name
embedding_dimension=384,
embedding_model="all-MiniLM-L6-v2",
provider_id=vector_io_provider,
)
# insert documents using the custom vector db name
llama_stack_api.client.tool_runtime.rag_tool.insert(
vector_db_id=vector_db_name, # Use the user-provided name
documents=documents,
chunk_size_in_tokens=512,
)
st.success("Vector database created successfully!")
st.subheader("RAG Parameters", divider=True)
rag_mode = st.radio(
"RAG mode",
["Direct", "Agent-based"],
captions=[
"RAG is performed by directly retrieving the information and augmenting the user query",
"RAG is performed by an agent activating a dedicated knowledge search tool.",
],
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
# select memory banks
vector_dbs = llama_stack_api.client.vector_dbs.list()
vector_dbs = [vector_db.identifier for vector_db in vector_dbs]
selected_vector_dbs = st.multiselect(
label="Select Document Collections to use in RAG queries",
options=vector_dbs,
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
st.subheader("Inference Parameters", divider=True)
available_models = llama_stack_api.client.models.list()
available_models = [model.identifier for model in available_models if model.model_type == "llm"]
selected_model = st.selectbox(
label="Choose a model",
options=available_models,
index=0,
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
system_prompt = st.text_area(
"System Prompt",
value="You are a helpful assistant. ",
help="Initial instructions given to the AI to set its behavior and context",
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
temperature = st.slider(
"Temperature",
min_value=0.0,
max_value=1.0,
value=0.0,
step=0.1,
help="Controls the randomness of the response. Higher values make the output more creative and unexpected, lower values make it more conservative and predictable",
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
top_p = st.slider(
"Top P",
min_value=0.0,
max_value=1.0,
value=0.95,
step=0.1,
on_change=reset_agent_and_chat,
disabled=should_disable_input(),
)
# Add clear chat button to sidebar
if st.button("Clear Chat", use_container_width=True):
reset_agent_and_chat()
st.rerun()
# Chat Interface
if "messages" not in st.session_state:
st.session_state.messages = []
if "displayed_messages" not in st.session_state:
st.session_state.displayed_messages = []
# Display chat history
for message in st.session_state.displayed_messages:
with st.chat_message(message["role"]):
st.markdown(message["content"])
if temperature > 0.0:
strategy = {
"type": "top_p",
"temperature": temperature,
"top_p": top_p,
}
else:
strategy = {"type": "greedy"}
@st.cache_resource
def create_agent():
return Agent(
llama_stack_api.client,
model=selected_model,
instructions=system_prompt,
sampling_params={
"strategy": strategy,
},
tools=[
dict(
name="builtin::rag/knowledge_search",
args={
"vector_db_ids": list(selected_vector_dbs),
},
)
],
)
if rag_mode == "Agent-based":
agent = create_agent()
if "agent_session_id" not in st.session_state:
st.session_state["agent_session_id"] = agent.create_session(session_name=f"rag_demo_{uuid.uuid4()}")
session_id = st.session_state["agent_session_id"]
def agent_process_prompt(prompt):
# Add user message to chat history
st.session_state.messages.append({"role": "user", "content": prompt})
# Send the prompt to the agent
response = agent.create_turn(
messages=[
{
"role": "user",
"content": prompt,
}
],
session_id=session_id,
)
# Display assistant response
with st.chat_message("assistant"):
retrieval_message_placeholder = st.empty()
message_placeholder = st.empty()
full_response = ""
retrieval_response = ""
for log in AgentEventLogger().log(response):
log.print()
if log.role == "tool_execution":
retrieval_response += log.content.replace("====", "").strip()
retrieval_message_placeholder.info(retrieval_response)
else:
full_response += log.content
message_placeholder.markdown(full_response + "")
message_placeholder.markdown(full_response)
st.session_state.messages.append({"role": "assistant", "content": full_response})
st.session_state.displayed_messages.append({"role": "assistant", "content": full_response})
def direct_process_prompt(prompt):
# Add the system prompt in the beginning of the conversation
if len(st.session_state.messages) == 0:
st.session_state.messages.append({"role": "system", "content": system_prompt})
# Query the vector DB
rag_response = llama_stack_api.client.tool_runtime.rag_tool.query(
content=prompt, vector_db_ids=list(selected_vector_dbs)
)
prompt_context = rag_response.content
with st.chat_message("assistant"):
retrieval_message_placeholder = st.empty()
message_placeholder = st.empty()
full_response = ""
retrieval_response = ""
# Display the retrieved content
retrieval_response += str(prompt_context)
retrieval_message_placeholder.info(retrieval_response)
# Construct the extended prompt
extended_prompt = f"Please answer the following query using the context below.\n\nCONTEXT:\n{prompt_context}\n\nQUERY:\n{prompt}"
# Run inference directly
st.session_state.messages.append({"role": "user", "content": extended_prompt})
response = llama_stack_api.client.inference.chat_completion(
messages=st.session_state.messages,
model_id=selected_model,
sampling_params={
"strategy": strategy,
},
stream=True,
)
# Display assistant response
for chunk in response:
response_delta = chunk.event.delta
if isinstance(response_delta, ToolCallDelta):
retrieval_response += response_delta.tool_call.replace("====", "").strip()
retrieval_message_placeholder.info(retrieval_response)
else:
full_response += chunk.event.delta.text
message_placeholder.markdown(full_response + "")
message_placeholder.markdown(full_response)
response_dict = {"role": "assistant", "content": full_response, "stop_reason": "end_of_message"}
st.session_state.messages.append(response_dict)
st.session_state.displayed_messages.append(response_dict)
# Chat input
if prompt := st.chat_input("Ask a question about your documents"):
# Add user message to chat history
st.session_state.displayed_messages.append({"role": "user", "content": prompt})
# Display user message
with st.chat_message("user"):
st.markdown(prompt)
# store the prompt to process it after page refresh
st.session_state.prompt = prompt
# force page refresh to disable the settings widgets
st.rerun()
if "prompt" in st.session_state and st.session_state.prompt is not None:
if rag_mode == "Agent-based":
agent_process_prompt(st.session_state.prompt)
else: # rag_mode == "Direct"
direct_process_prompt(st.session_state.prompt)
st.session_state.prompt = None
rag_chat_page()