Expand pipelines to fix streaming of tokens

This commit is contained in:
Vivek Khandelwal
2023-07-31 15:40:50 +00:00
parent 206c1b70f4
commit 98fb6c52df
2 changed files with 434 additions and 50 deletions

View File

@@ -0,0 +1,432 @@
"""Load question answering chains."""
from __future__ import annotations
from typing import (
Any,
Mapping,
Optional,
Dict,
List,
Sequence,
Tuple,
Union,
Protocol,
)
from langchain.base_language import BaseLanguageModel
from langchain.callbacks.base import BaseCallbackManager
from langchain.chains.question_answering import stuff_prompt
from langchain.prompts.base import BasePromptTemplate
from langchain.docstore.document import Document
from abc import ABC, abstractmethod
from langchain.chains.base import Chain
from langchain.callbacks.manager import (
CallbackManager,
CallbackManagerForChainRun,
Callbacks,
)
from langchain.input import get_colored_text
from langchain.load.dump import dumpd
from langchain.prompts.prompt import PromptTemplate
from langchain.schema import LLMResult, PromptValue
from pydantic import Extra, Field, root_validator
def format_document(doc: Document, prompt: BasePromptTemplate) -> str:
"""Format a document into a string based on a prompt template."""
base_info = {"page_content": doc.page_content}
base_info.update(doc.metadata)
missing_metadata = set(prompt.input_variables).difference(base_info)
if len(missing_metadata) > 0:
required_metadata = [
iv for iv in prompt.input_variables if iv != "page_content"
]
raise ValueError(
f"Document prompt requires documents to have metadata variables: "
f"{required_metadata}. Received document with missing metadata: "
f"{list(missing_metadata)}."
)
document_info = {k: base_info[k] for k in prompt.input_variables}
return prompt.format(**document_info)
class BaseCombineDocumentsChain(Chain, ABC):
"""Base interface for chains combining documents."""
input_key: str = "input_documents" #: :meta private:
output_key: str = "output_text" #: :meta private:
@property
def input_keys(self) -> List[str]:
"""Expect input key.
:meta private:
"""
return [self.input_key]
@property
def output_keys(self) -> List[str]:
"""Return output key.
:meta private:
"""
return [self.output_key]
def prompt_length(
self, docs: List[Document], **kwargs: Any
) -> Optional[int]:
"""Return the prompt length given the documents passed in.
Returns None if the method does not depend on the prompt length.
"""
return None
@abstractmethod
def combine_docs(
self, docs: List[Document], **kwargs: Any
) -> Tuple[str, dict]:
"""Combine documents into a single string."""
def _call(
self,
inputs: Dict[str, List[Document]],
run_manager: Optional[CallbackManagerForChainRun] = None,
) -> Dict[str, str]:
_run_manager = (
run_manager or CallbackManagerForChainRun.get_noop_manager()
)
docs = inputs[self.input_key]
# Other keys are assumed to be needed for LLM prediction
other_keys = {k: v for k, v in inputs.items() if k != self.input_key}
output, extra_return_dict = self.combine_docs(
docs, callbacks=_run_manager.get_child(), **other_keys
)
extra_return_dict[self.output_key] = output
return extra_return_dict
class LLMChain(Chain):
"""Chain to run queries against LLMs.
Example:
.. code-block:: python
from langchain import LLMChain, OpenAI, PromptTemplate
prompt_template = "Tell me a {adjective} joke"
prompt = PromptTemplate(
input_variables=["adjective"], template=prompt_template
)
llm = LLMChain(llm=OpenAI(), prompt=prompt)
"""
@property
def lc_serializable(self) -> bool:
return True
prompt: BasePromptTemplate
"""Prompt object to use."""
llm: BaseLanguageModel
output_key: str = "text" #: :meta private:
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
@property
def input_keys(self) -> List[str]:
"""Will be whatever keys the prompt expects.
:meta private:
"""
return self.prompt.input_variables
@property
def output_keys(self) -> List[str]:
"""Will always return text key.
:meta private:
"""
return [self.output_key]
def _call(
self,
inputs: Dict[str, Any],
run_manager: Optional[CallbackManagerForChainRun] = None,
) -> Dict[str, str]:
response = self.generate([inputs], run_manager=run_manager)
return self.create_outputs(response)[0]
def generate(
self,
input_list: List[Dict[str, Any]],
run_manager: Optional[CallbackManagerForChainRun] = None,
) -> LLMResult:
"""Generate LLM result from inputs."""
prompts, stop = self.prep_prompts(input_list, run_manager=run_manager)
return self.llm.generate_prompt(
prompts,
stop,
callbacks=run_manager.get_child() if run_manager else None,
)
def prep_prompts(
self,
input_list: List[Dict[str, Any]],
run_manager: Optional[CallbackManagerForChainRun] = None,
) -> Tuple[List[PromptValue], Optional[List[str]]]:
"""Prepare prompts from inputs."""
stop = None
if "stop" in input_list[0]:
stop = input_list[0]["stop"]
prompts = []
for inputs in input_list:
selected_inputs = {
k: inputs[k] for k in self.prompt.input_variables
}
prompt = self.prompt.format_prompt(**selected_inputs)
_colored_text = get_colored_text(prompt.to_string(), "green")
_text = "Prompt after formatting:\n" + _colored_text
if run_manager:
run_manager.on_text(_text, end="\n", verbose=self.verbose)
if "stop" in inputs and inputs["stop"] != stop:
raise ValueError(
"If `stop` is present in any inputs, should be present in all."
)
prompts.append(prompt)
return prompts, stop
def apply(
self, input_list: List[Dict[str, Any]], callbacks: Callbacks = None
) -> List[Dict[str, str]]:
"""Utilize the LLM generate method for speed gains."""
callback_manager = CallbackManager.configure(
callbacks, self.callbacks, self.verbose
)
run_manager = callback_manager.on_chain_start(
dumpd(self),
{"input_list": input_list},
)
try:
response = self.generate(input_list, run_manager=run_manager)
except (KeyboardInterrupt, Exception) as e:
run_manager.on_chain_error(e)
raise e
outputs = self.create_outputs(response)
run_manager.on_chain_end({"outputs": outputs})
return outputs
def create_outputs(self, response: LLMResult) -> List[Dict[str, str]]:
"""Create outputs from response."""
return [
# Get the text of the top generated string.
{self.output_key: generation[0].text}
for generation in response.generations
]
def predict(self, callbacks: Callbacks = None, **kwargs: Any) -> str:
"""Format prompt with kwargs and pass to LLM.
Args:
callbacks: Callbacks to pass to LLMChain
**kwargs: Keys to pass to prompt template.
Returns:
Completion from LLM.
Example:
.. code-block:: python
completion = llm.predict(adjective="funny")
"""
return self(kwargs, callbacks=callbacks)[self.output_key]
def predict_and_parse(
self, callbacks: Callbacks = None, **kwargs: Any
) -> Union[str, List[str], Dict[str, Any]]:
"""Call predict and then parse the results."""
result = self.predict(callbacks=callbacks, **kwargs)
if self.prompt.output_parser is not None:
return self.prompt.output_parser.parse(result)
else:
return result
def apply_and_parse(
self, input_list: List[Dict[str, Any]], callbacks: Callbacks = None
) -> Sequence[Union[str, List[str], Dict[str, str]]]:
"""Call apply and then parse the results."""
result = self.apply(input_list, callbacks=callbacks)
return self._parse_result(result)
def _parse_result(
self, result: List[Dict[str, str]]
) -> Sequence[Union[str, List[str], Dict[str, str]]]:
if self.prompt.output_parser is not None:
return [
self.prompt.output_parser.parse(res[self.output_key])
for res in result
]
else:
return result
@property
def _chain_type(self) -> str:
return "llm_chain"
@classmethod
def from_string(cls, llm: BaseLanguageModel, template: str) -> LLMChain:
"""Create LLMChain from LLM and template."""
prompt_template = PromptTemplate.from_template(template)
return cls(llm=llm, prompt=prompt_template)
def _get_default_document_prompt() -> PromptTemplate:
return PromptTemplate(
input_variables=["page_content"], template="{page_content}"
)
class StuffDocumentsChain(BaseCombineDocumentsChain):
"""Chain that combines documents by stuffing into context."""
llm_chain: LLMChain
"""LLM wrapper to use after formatting documents."""
document_prompt: BasePromptTemplate = Field(
default_factory=_get_default_document_prompt
)
"""Prompt to use to format each document."""
document_variable_name: str
"""The variable name in the llm_chain to put the documents in.
If only one variable in the llm_chain, this need not be provided."""
document_separator: str = "\n\n"
"""The string with which to join the formatted documents"""
class Config:
"""Configuration for this pydantic object."""
extra = Extra.forbid
arbitrary_types_allowed = True
@root_validator(pre=True)
def get_default_document_variable_name(cls, values: Dict) -> Dict:
"""Get default document variable name, if not provided."""
llm_chain_variables = values["llm_chain"].prompt.input_variables
if "document_variable_name" not in values:
if len(llm_chain_variables) == 1:
values["document_variable_name"] = llm_chain_variables[0]
else:
raise ValueError(
"document_variable_name must be provided if there are "
"multiple llm_chain_variables"
)
else:
if values["document_variable_name"] not in llm_chain_variables:
raise ValueError(
f"document_variable_name {values['document_variable_name']} was "
f"not found in llm_chain input_variables: {llm_chain_variables}"
)
return values
def _get_inputs(self, docs: List[Document], **kwargs: Any) -> dict:
# Format each document according to the prompt
doc_strings = [
format_document(doc, self.document_prompt) for doc in docs
]
# Join the documents together to put them in the prompt.
inputs = {
k: v
for k, v in kwargs.items()
if k in self.llm_chain.prompt.input_variables
}
inputs[self.document_variable_name] = self.document_separator.join(
doc_strings
)
return inputs
def prompt_length(
self, docs: List[Document], **kwargs: Any
) -> Optional[int]:
"""Get the prompt length by formatting the prompt."""
inputs = self._get_inputs(docs, **kwargs)
prompt = self.llm_chain.prompt.format(**inputs)
return self.llm_chain.llm.get_num_tokens(prompt)
def combine_docs(
self, docs: List[Document], callbacks: Callbacks = None, **kwargs: Any
) -> Tuple[str, dict]:
"""Stuff all documents into one prompt and pass to LLM."""
inputs = self._get_inputs(docs, **kwargs)
# Call predict on the LLM.
return self.llm_chain.predict(callbacks=callbacks, **inputs), {}
@property
def _chain_type(self) -> str:
return "stuff_documents_chain"
class LoadingCallable(Protocol):
"""Interface for loading the combine documents chain."""
def __call__(
self, llm: BaseLanguageModel, **kwargs: Any
) -> BaseCombineDocumentsChain:
"""Callable to load the combine documents chain."""
def _load_stuff_chain(
llm: BaseLanguageModel,
prompt: Optional[BasePromptTemplate] = None,
document_variable_name: str = "context",
verbose: Optional[bool] = None,
callback_manager: Optional[BaseCallbackManager] = None,
callbacks: Callbacks = None,
**kwargs: Any,
) -> StuffDocumentsChain:
_prompt = prompt or stuff_prompt.PROMPT_SELECTOR.get_prompt(llm)
llm_chain = LLMChain(
llm=llm,
prompt=_prompt,
verbose=verbose,
callback_manager=callback_manager,
callbacks=callbacks,
)
# TODO: document prompt
return StuffDocumentsChain(
llm_chain=llm_chain,
document_variable_name=document_variable_name,
verbose=verbose,
callback_manager=callback_manager,
**kwargs,
)
def load_qa_chain(
llm: BaseLanguageModel,
chain_type: str = "stuff",
verbose: Optional[bool] = None,
callback_manager: Optional[BaseCallbackManager] = None,
**kwargs: Any,
) -> BaseCombineDocumentsChain:
"""Load question answering chain.
Args:
llm: Language Model to use in the chain.
chain_type: Type of document combining chain to use. Should be one of "stuff",
"map_reduce", "map_rerank", and "refine".
verbose: Whether chains should be run in verbose mode or not. Note that this
applies to all chains that make up the final chain.
callback_manager: Callback manager to use for the chain.
Returns:
A chain to use for question answering.
"""
loader_mapping: Mapping[str, LoadingCallable] = {
"stuff": _load_stuff_chain,
}
if chain_type not in loader_mapping:
raise ValueError(
f"Got unsupported chain type: {chain_type}. "
f"Should be one of {loader_mapping.keys()}"
)
return loader_mapping[chain_type](
llm, verbose=verbose, callback_manager=callback_manager, **kwargs
)

View File

@@ -87,7 +87,7 @@ from langchain.document_loaders import (
UnstructuredExcelLoader,
)
from langchain.text_splitter import RecursiveCharacterTextSplitter, Language
from langchain.chains.question_answering import load_qa_chain
from expanded_pipelines import load_qa_chain
from langchain.docstore.document import Document
from langchain import PromptTemplate, HuggingFaceTextGenInference
from langchain.vectorstores import Chroma
@@ -2958,56 +2958,8 @@ def get_similarity_chain(
template=template,
)
chain = load_qa_chain(llm, prompt=prompt)
else:
# only if use_openai_model = True, unused normally except in testing
chain = load_qa_with_sources_chain(llm)
if not use_context:
chain_kwargs = dict(input_documents=[], question=query)
else:
chain_kwargs = dict(input_documents=docs, question=query)
chain_kwargs = dict(input_documents=docs, question=query)
target = wrapped_partial(chain, chain_kwargs)
elif langchain_action in [
LangChainAction.SUMMARIZE_MAP.value,
LangChainAction.SUMMARIZE_REFINE,
LangChainAction.SUMMARIZE_ALL.value,
]:
from langchain.chains.summarize import load_summarize_chain
if langchain_action == LangChainAction.SUMMARIZE_MAP.value:
prompt = PromptTemplate(
input_variables=["text"], template=template
)
chain = load_summarize_chain(
llm,
chain_type="map_reduce",
map_prompt=prompt,
combine_prompt=prompt,
return_intermediate_steps=True,
)
target = wrapped_partial(
chain, {"input_documents": docs}
) # , return_only_outputs=True)
elif langchain_action == LangChainAction.SUMMARIZE_ALL.value:
assert use_template
prompt = PromptTemplate(
input_variables=["text"], template=template
)
chain = load_summarize_chain(
llm,
chain_type="stuff",
prompt=prompt,
return_intermediate_steps=True,
)
target = wrapped_partial(chain)
elif langchain_action == LangChainAction.SUMMARIZE_REFINE.value:
chain = load_summarize_chain(
llm, chain_type="refine", return_intermediate_steps=True
)
target = wrapped_partial(chain)
else:
raise RuntimeError(
"No such langchain_action=%s" % langchain_action
)
else:
raise RuntimeError("No such langchain_action=%s" % langchain_action)