Allow passing a system prompt (#1318)
This commit is contained in:
parent
9c192ddd73
commit
64ed9cd872
File diff suppressed because it is too large
Load Diff
|
@ -28,10 +28,14 @@ class ChatBody(BaseModel):
|
|||
"examples": [
|
||||
{
|
||||
"messages": [
|
||||
{
|
||||
"role": "system",
|
||||
"content": "You are a rapper. Always answer with a rap.",
|
||||
},
|
||||
{
|
||||
"role": "user",
|
||||
"content": "How do you fry an egg?",
|
||||
}
|
||||
},
|
||||
],
|
||||
"stream": False,
|
||||
"use_context": True,
|
||||
|
@ -56,6 +60,9 @@ def chat_completion(
|
|||
) -> OpenAICompletion | StreamingResponse:
|
||||
"""Given a list of messages comprising a conversation, return a response.
|
||||
|
||||
Optionally include an initial `role: system` message to influence the way
|
||||
the LLM answers.
|
||||
|
||||
If `use_context` is set to `true`, the model will use context coming
|
||||
from the ingested documents to create the response. The documents being used can
|
||||
be filtered using the `context_filter` and passing the document IDs to be used.
|
||||
|
@ -79,7 +86,9 @@ def chat_completion(
|
|||
]
|
||||
if body.stream:
|
||||
completion_gen = service.stream_chat(
|
||||
all_messages, body.use_context, body.context_filter
|
||||
messages=all_messages,
|
||||
use_context=body.use_context,
|
||||
context_filter=body.context_filter,
|
||||
)
|
||||
return StreamingResponse(
|
||||
to_openai_sse_stream(
|
||||
|
@ -89,7 +98,11 @@ def chat_completion(
|
|||
media_type="text/event-stream",
|
||||
)
|
||||
else:
|
||||
completion = service.chat(all_messages, body.use_context, body.context_filter)
|
||||
completion = service.chat(
|
||||
messages=all_messages,
|
||||
use_context=body.use_context,
|
||||
context_filter=body.context_filter,
|
||||
)
|
||||
return to_openai_response(
|
||||
completion.response, completion.sources if body.include_sources else None
|
||||
)
|
||||
|
|
|
@ -1,12 +1,13 @@
|
|||
from dataclasses import dataclass
|
||||
|
||||
from injector import inject, singleton
|
||||
from llama_index import ServiceContext, StorageContext, VectorStoreIndex
|
||||
from llama_index.chat_engine import ContextChatEngine
|
||||
from llama_index.chat_engine import ContextChatEngine, SimpleChatEngine
|
||||
from llama_index.chat_engine.types import (
|
||||
BaseChatEngine,
|
||||
)
|
||||
from llama_index.indices.postprocessor import MetadataReplacementPostProcessor
|
||||
from llama_index.llm_predictor.utils import stream_chat_response_to_tokens
|
||||
from llama_index.llms import ChatMessage
|
||||
from llama_index.llms import ChatMessage, MessageRole
|
||||
from llama_index.types import TokenGen
|
||||
from pydantic import BaseModel
|
||||
|
||||
|
@ -30,6 +31,40 @@ class CompletionGen(BaseModel):
|
|||
sources: list[Chunk] | None = None
|
||||
|
||||
|
||||
@dataclass
|
||||
class ChatEngineInput:
|
||||
system_message: ChatMessage | None = None
|
||||
last_message: ChatMessage | None = None
|
||||
chat_history: list[ChatMessage] | None = None
|
||||
|
||||
@classmethod
|
||||
def from_messages(cls, messages: list[ChatMessage]) -> "ChatEngineInput":
|
||||
# Detect if there is a system message, extract the last message and chat history
|
||||
system_message = (
|
||||
messages[0]
|
||||
if len(messages) > 0 and messages[0].role == MessageRole.SYSTEM
|
||||
else None
|
||||
)
|
||||
last_message = (
|
||||
messages[-1]
|
||||
if len(messages) > 0 and messages[-1].role == MessageRole.USER
|
||||
else None
|
||||
)
|
||||
# Remove from messages list the system message and last message,
|
||||
# if they exist. The rest is the chat history.
|
||||
if system_message:
|
||||
messages.pop(0)
|
||||
if last_message:
|
||||
messages.pop(-1)
|
||||
chat_history = messages if len(messages) > 0 else None
|
||||
|
||||
return cls(
|
||||
system_message=system_message,
|
||||
last_message=last_message,
|
||||
chat_history=chat_history,
|
||||
)
|
||||
|
||||
|
||||
@singleton
|
||||
class ChatService:
|
||||
@inject
|
||||
|
@ -58,18 +93,28 @@ class ChatService:
|
|||
)
|
||||
|
||||
def _chat_engine(
|
||||
self, context_filter: ContextFilter | None = None
|
||||
self,
|
||||
system_prompt: str | None = None,
|
||||
use_context: bool = False,
|
||||
context_filter: ContextFilter | None = None,
|
||||
) -> BaseChatEngine:
|
||||
vector_index_retriever = self.vector_store_component.get_retriever(
|
||||
index=self.index, context_filter=context_filter
|
||||
)
|
||||
return ContextChatEngine.from_defaults(
|
||||
retriever=vector_index_retriever,
|
||||
service_context=self.service_context,
|
||||
node_postprocessors=[
|
||||
MetadataReplacementPostProcessor(target_metadata_key="window"),
|
||||
],
|
||||
)
|
||||
if use_context:
|
||||
vector_index_retriever = self.vector_store_component.get_retriever(
|
||||
index=self.index, context_filter=context_filter
|
||||
)
|
||||
return ContextChatEngine.from_defaults(
|
||||
system_prompt=system_prompt,
|
||||
retriever=vector_index_retriever,
|
||||
service_context=self.service_context,
|
||||
node_postprocessors=[
|
||||
MetadataReplacementPostProcessor(target_metadata_key="window"),
|
||||
],
|
||||
)
|
||||
else:
|
||||
return SimpleChatEngine.from_defaults(
|
||||
system_prompt=system_prompt,
|
||||
service_context=self.service_context,
|
||||
)
|
||||
|
||||
def stream_chat(
|
||||
self,
|
||||
|
@ -77,24 +122,34 @@ class ChatService:
|
|||
use_context: bool = False,
|
||||
context_filter: ContextFilter | None = None,
|
||||
) -> CompletionGen:
|
||||
if use_context:
|
||||
last_message = messages[-1].content
|
||||
chat_engine = self._chat_engine(context_filter=context_filter)
|
||||
streaming_response = chat_engine.stream_chat(
|
||||
message=last_message if last_message is not None else "",
|
||||
chat_history=messages[:-1],
|
||||
)
|
||||
sources = [
|
||||
Chunk.from_node(node) for node in streaming_response.source_nodes
|
||||
]
|
||||
completion_gen = CompletionGen(
|
||||
response=streaming_response.response_gen, sources=sources
|
||||
)
|
||||
else:
|
||||
stream = self.llm_service.llm.stream_chat(messages)
|
||||
completion_gen = CompletionGen(
|
||||
response=stream_chat_response_to_tokens(stream)
|
||||
)
|
||||
chat_engine_input = ChatEngineInput.from_messages(messages)
|
||||
last_message = (
|
||||
chat_engine_input.last_message.content
|
||||
if chat_engine_input.last_message
|
||||
else None
|
||||
)
|
||||
system_prompt = (
|
||||
chat_engine_input.system_message.content
|
||||
if chat_engine_input.system_message
|
||||
else None
|
||||
)
|
||||
chat_history = (
|
||||
chat_engine_input.chat_history if chat_engine_input.chat_history else None
|
||||
)
|
||||
|
||||
chat_engine = self._chat_engine(
|
||||
system_prompt=system_prompt,
|
||||
use_context=use_context,
|
||||
context_filter=context_filter,
|
||||
)
|
||||
streaming_response = chat_engine.stream_chat(
|
||||
message=last_message if last_message is not None else "",
|
||||
chat_history=chat_history,
|
||||
)
|
||||
sources = [Chunk.from_node(node) for node in streaming_response.source_nodes]
|
||||
completion_gen = CompletionGen(
|
||||
response=streaming_response.response_gen, sources=sources
|
||||
)
|
||||
return completion_gen
|
||||
|
||||
def chat(
|
||||
|
@ -103,18 +158,30 @@ class ChatService:
|
|||
use_context: bool = False,
|
||||
context_filter: ContextFilter | None = None,
|
||||
) -> Completion:
|
||||
if use_context:
|
||||
last_message = messages[-1].content
|
||||
chat_engine = self._chat_engine(context_filter=context_filter)
|
||||
wrapped_response = chat_engine.chat(
|
||||
message=last_message if last_message is not None else "",
|
||||
chat_history=messages[:-1],
|
||||
)
|
||||
sources = [Chunk.from_node(node) for node in wrapped_response.source_nodes]
|
||||
completion = Completion(response=wrapped_response.response, sources=sources)
|
||||
else:
|
||||
chat_response = self.llm_service.llm.chat(messages)
|
||||
response_content = chat_response.message.content
|
||||
response = response_content if response_content is not None else ""
|
||||
completion = Completion(response=response)
|
||||
chat_engine_input = ChatEngineInput.from_messages(messages)
|
||||
last_message = (
|
||||
chat_engine_input.last_message.content
|
||||
if chat_engine_input.last_message
|
||||
else None
|
||||
)
|
||||
system_prompt = (
|
||||
chat_engine_input.system_message.content
|
||||
if chat_engine_input.system_message
|
||||
else None
|
||||
)
|
||||
chat_history = (
|
||||
chat_engine_input.chat_history if chat_engine_input.chat_history else None
|
||||
)
|
||||
|
||||
chat_engine = self._chat_engine(
|
||||
system_prompt=system_prompt,
|
||||
use_context=use_context,
|
||||
context_filter=context_filter,
|
||||
)
|
||||
wrapped_response = chat_engine.chat(
|
||||
message=last_message if last_message is not None else "",
|
||||
chat_history=chat_history,
|
||||
)
|
||||
sources = [Chunk.from_node(node) for node in wrapped_response.source_nodes]
|
||||
completion = Completion(response=wrapped_response.response, sources=sources)
|
||||
return completion
|
||||
|
|
|
@ -15,6 +15,7 @@ completions_router = APIRouter(prefix="/v1", dependencies=[Depends(authenticated
|
|||
|
||||
class CompletionsBody(BaseModel):
|
||||
prompt: str
|
||||
system_prompt: str | None = None
|
||||
use_context: bool = False
|
||||
context_filter: ContextFilter | None = None
|
||||
include_sources: bool = True
|
||||
|
@ -25,6 +26,7 @@ class CompletionsBody(BaseModel):
|
|||
"examples": [
|
||||
{
|
||||
"prompt": "How do you fry an egg?",
|
||||
"system_prompt": "You are a rapper. Always answer with a rap.",
|
||||
"stream": False,
|
||||
"use_context": False,
|
||||
"include_sources": False,
|
||||
|
@ -46,7 +48,11 @@ def prompt_completion(
|
|||
) -> OpenAICompletion | StreamingResponse:
|
||||
"""We recommend most users use our Chat completions API.
|
||||
|
||||
Given a prompt, the model will return one predicted completion. If `use_context`
|
||||
Given a prompt, the model will return one predicted completion.
|
||||
|
||||
Optionally include a `system_prompt` to influence the way the LLM answers.
|
||||
|
||||
If `use_context`
|
||||
is set to `true`, the model will use context coming from the ingested documents
|
||||
to create the response. The documents being used can be filtered using the
|
||||
`context_filter` and passing the document IDs to be used. Ingested documents IDs
|
||||
|
@ -64,9 +70,13 @@ def prompt_completion(
|
|||
"finish_reason":null}]}
|
||||
```
|
||||
"""
|
||||
message = OpenAIMessage(content=body.prompt, role="user")
|
||||
messages = [OpenAIMessage(content=body.prompt, role="user")]
|
||||
# If system prompt is passed, create a fake message with the system prompt.
|
||||
if body.system_prompt:
|
||||
messages.insert(0, OpenAIMessage(content=body.system_prompt, role="system"))
|
||||
|
||||
chat_body = ChatBody(
|
||||
messages=[message],
|
||||
messages=messages,
|
||||
use_context=body.use_context,
|
||||
stream=body.stream,
|
||||
include_sources=body.include_sources,
|
||||
|
|
|
@ -116,6 +116,17 @@ class PrivateGptUi:
|
|||
all_messages = [*build_history(), new_message]
|
||||
match mode:
|
||||
case "Query Docs":
|
||||
# Add a system message to force the behaviour of the LLM
|
||||
# to answer only questions about the provided context.
|
||||
all_messages.insert(
|
||||
0,
|
||||
ChatMessage(
|
||||
content="You can only answer questions about the provided context. If you know the answer "
|
||||
"but it is not based in the provided context, don't provide the answer, just state "
|
||||
"the answer is not in the context provided.",
|
||||
role=MessageRole.SYSTEM,
|
||||
),
|
||||
)
|
||||
query_stream = self._chat_service.stream_chat(
|
||||
messages=all_messages,
|
||||
use_context=True,
|
||||
|
|
|
@ -22,6 +22,7 @@ ui:
|
|||
|
||||
llm:
|
||||
mode: local
|
||||
|
||||
embedding:
|
||||
# Should be matching the value above in most cases
|
||||
mode: local
|
||||
|
|
Loading…
Reference in New Issue