[colossal-llama2] add stream chat examlple for chat version model (#5428)

* add stream chat for chat version

* remove os.system clear

* modify function name
pull/5430/head
Camille Zhong 9 months ago committed by GitHub
parent 68f55a709c
commit 743e7fad2f
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@ -0,0 +1,247 @@
from copy import deepcopy
from typing import Optional, List, Dict, Tuple, Callable, Any
import torch
from torch import nn
from transformers import PreTrainedTokenizer
from transformers.utils import logging
from transformers.generation.utils import GenerationConfig, LogitsProcessorList, StoppingCriteriaList
logger = logging.get_logger(__name__)
def get_prompt_template(
input_query:str,
history:List[Dict]= None,
roles:list = ["", "Human", "Assistant"],
) -> str:
"""
Generates a prompt template for chat models based on input and history.
Args:
input_query (str): User's current input query.
history (List[Dict], optional): List of past conversations, each a dict with 'role' and 'message'.
roles (list): Specifies the roles in the conversation, defaults to ["", "Human", "Assistant"].
Returns:
str: A formatted prompt including the input query and history.
"""
prompt = ""
if history is None:
new_history = []
else:
new_history = deepcopy(history)
new_history.append({"role": roles[1], "message": input_query.strip()})
new_history.append({"role": roles[2], "message": None})
for _, item in enumerate(new_history):
role = item.get("role")
message = item.get("message")
if role == roles[0]:
prompt += f"<s>{message}\n\n"
else:
if message:
prompt += f"{role}: <s>{message}</s>"
else:
prompt += f"{role}: <s>"
return prompt
@torch.inference_mode()
def streaming_chat(
model: Any,
tokenizer: PreTrainedTokenizer,
input_query: str,
history: List[Dict] = None,
roles: list = ["", "Human", "Assistant"],
past_key_values: Tuple[Tuple[torch.FloatTensor, Any], Any] = None,
temperature: float = 0.8,
top_p: float = 0.95,
top_k: int = 50,
do_sample: bool = True,
length_penalty: float = 1.2,
max_new_tokens: int = 512,
logits_processor: LogitsProcessorList = None,
return_past_key_values: bool = False,
**kwargs,
):
"""
Streaming chat responses generation with a given model and tokenizer.
Args:
model (Any): The language model to generate responses.
tokenizer (PreTrainedTokenizer): Tokenizer compatible with the model, used for encoding inputs and decoding responses.
input_query (str): The current user input to respond to.
history (List[Dict], optional): A list of past conversations, where each conversation is a dictionary with keys 'role' and 'message'.
roles (list): Roles involved in the conversation, defaults to ["", "Human", "Assistant"].
past_key_values (Tuple[Tuple[torch.FloatTensor, Any], Any], optional): Past key values for incremental decoding.
temperature (float): The temperature value for token sampling, defaults to 0.8.
top_p (float): Nucleus sampling probability threshold, defaults to 0.95.
top_k (int): Top-K filtering threshold, defaults to 50.
do_sample (bool): Whether to sample responses, defaults to True.
length_penalty (float): Penalty for response length, defaults to 1.2.
max_new_tokens (int): Maximum number of new tokens to generate, defaults to 512.
logits_processor (LogitsProcessorList, optional): Custom logits processors, defaults to None.
return_past_key_values (bool): Whether to return past key values for further incremental decoding, defaults to False.
**kwargs: Additional keyword arguments for generation.
Yields:
Tuple[str, List[Dict], Optional[Tuple[Tuple[torch.FloatTensor, Any], Any]]]: A tuple containing the generated response, updated history, and
optionally the updated past key values if `return_past_key_values` is True.
Ensures padding is on the left side for the tokenizer.
"""
assert tokenizer.padding_side == "left", "Current generation only supports left padding."
if history is None:
history = []
if logits_processor is None:
logits_processor = LogitsProcessorList()
generation_kwargs = {
'temperature': temperature,
'top_p': top_p,
'top_k': top_k,
'do_sample': do_sample,
'max_new_tokens': max_new_tokens,
'length_penalty': length_penalty,
'use_cache': True,
**kwargs
}
prompt_str = get_prompt_template(input_query, history=history, roles=roles)
eos_token_id = [tokenizer.eos_token_id]
inputs = tokenizer(prompt_str, return_tensors="pt").to(model.device)
history.append({"role": roles[1], "message": input_query.strip()})
history.append({"role": roles[2], "message": None})
for outputs in stream_generate(model, **inputs, past_key_values=past_key_values,
eos_token_id=eos_token_id, return_past_key_values=return_past_key_values,
**generation_kwargs):
if return_past_key_values:
outputs, past_key_values = outputs
outputs = outputs.tolist()[0][len(inputs["input_ids"][0]):-1]
response = tokenizer.decode(outputs)
history[-1]["message"] = response.strip()
if return_past_key_values:
yield response, history, past_key_values
else:
yield response, history
@torch.inference_mode()
def stream_generate(
model: Any,
input_ids: torch.Tensor,
generation_config: Optional[GenerationConfig] = None,
logits_processor: Optional[LogitsProcessorList] = None,
stopping_criteria: Optional[StoppingCriteriaList] = None,
prefix_allowed_tokens_fn: Optional[Callable[[int, torch.Tensor], List[int]]] = None,
return_past_key_values: bool = False,
**kwargs,
):
"""
Generates sequences of token ids using the specified model and generation parameters.
Adapted from https://huggingface.co/THUDM/chatglm3-6b/blob/main/modeling_chatglm.py
Args:
model (Any): The model used for generating sequences of token ids.
input_ids (torch.Tensor): The sequence used as a prompt for the generation or as model inputs to the encoder.
generation_config (Optional[GenerationConfig]): The generation configuration to be used as base parametrization for the generation call.
logits_processor (Optional[LogitsProcessorList]): Custom logits processors that complement the default logits processors built from arguments
and generation config.
stopping_criteria (Optional[StoppingCriteriaList]): Custom stopping criteria that complement the default stopping criteria built from arguments
and a generation config.
prefix_allowed_tokens_fn (Optional[Callable[[int, torch.Tensor], List[int]]]): Function to constrain token generation.
return_past_key_values (bool): Whether to return past key values for further incremental decoding, defaults to False.
**kwargs: Additional parameters for model generation.
Yields:
torch.Tensor: The generated token IDs, updated after each generation step.
Optional[Tuple[Tuple[torch.FloatTensor, Any], Any]]: The past key values, returned if `return_past_key_values` is True, defaults to False.
"""
input_ids_len = input_ids.size(1)
if generation_config is None:
generation_config = model.generation_config
generation_config = deepcopy(generation_config)
model_kwargs = generation_config.update(**kwargs)
eos_token_id = generation_config.eos_token_id
if isinstance(eos_token_id, int):
eos_token_id = [eos_token_id]
eos_token_id_tensor = torch.tensor(eos_token_id).to(input_ids.device) if eos_token_id is not None else None
if generation_config.max_new_tokens is not None:
generation_config.max_length = generation_config.max_new_tokens + input_ids_len
if input_ids_len >= generation_config.max_length:
input_ids_string = "decoder_input_ids" if model.config.is_encoder_decoder else "input_ids"
logger.warning(
f"Input length of {input_ids_string} is {input_ids_len}, but `max_length` is set to"
f" {generation_config.max_length}. This can lead to unexpected behavior. You should consider"
" increasing `max_new_tokens`."
)
logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
# prepare distribution pre_processing samplers
logits_processor = model._get_logits_processor(
generation_config=generation_config,
input_ids_seq_length=input_ids_len,
encoder_input_ids=input_ids,
prefix_allowed_tokens_fn=prefix_allowed_tokens_fn,
logits_processor=logits_processor,
)
# prepare stopping criteria
stopping_criteria = model._get_stopping_criteria(
generation_config=generation_config, stopping_criteria=stopping_criteria
)
logits_warper = model._get_logits_warper(generation_config)
unfinished_sequences = input_ids.new(input_ids.shape[0]).fill_(1)
scores = None
while True:
model_inputs = model.prepare_inputs_for_generation(input_ids, **model_kwargs)
# forward pass to get next token
outputs = model(
**model_inputs,
return_dict=True,
output_attentions=False,
output_hidden_states=False,
)
# NOTE: this is correct only in left padding mode
# pre-process distribution
next_token_logits = outputs.logits[:, -1, :]
next_token_scores = logits_processor(input_ids, next_token_logits)
next_token_scores = logits_warper(input_ids, next_token_scores)
# sample
probs = nn.functional.softmax(next_token_scores, dim=-1)
if generation_config.do_sample:
next_tokens = torch.multinomial(probs, num_samples=1).squeeze(1)
else:
next_tokens = torch.argmax(probs, dim=-1)
# update generated ids, model inputs, and length for next step
input_ids = torch.cat([input_ids, next_tokens[:, None]], dim=-1)
model_kwargs = model._update_model_kwargs_for_generation(
outputs, model_kwargs, is_encoder_decoder=model.config.is_encoder_decoder
)
unfinished_sequences = unfinished_sequences.mul(
next_tokens.tile(eos_token_id_tensor.shape[0], 1).ne(eos_token_id_tensor.unsqueeze(1)).prod(dim=0)
)
if return_past_key_values:
yield input_ids, outputs.past_key_values
else:
yield input_ids
# stop when each sentence is finished, or if exceed the maximum length
if unfinished_sequences.max() == 0 or stopping_criteria(input_ids, scores):
break

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import os
import argparse
from transformers import AutoTokenizer, AutoModelForCausalLM
from colossal_llama2.utils.stream_chat_patch import streaming_chat
SYSTEM = "A chat between a curious human and an artificial intelligence assistant. The assistant gives helpful, detailed, and polite answers to the human's questions."
def main(args):
model = AutoModelForCausalLM.from_pretrained(args.model_path).cuda().eval()
tokenizer = AutoTokenizer.from_pretrained(args.tokenizer_path)
past_key_values, history = None, []
roles = ["", "Human", "Assistant"]
history = []
history.append({"role": roles[0], "message": SYSTEM})
while True:
input_query = input(f"\n{roles[1]}: ")
if input_query.strip() == "exit":
break
if input_query.strip() == "clear":
past_key_values, history = None, []
continue
print(f"\n{roles[2]}: ", end="")
gen_len = 0
for response, history, past_key_values in streaming_chat(
model, tokenizer, input_query, history=history, roles=roles,
temperature = args.temperature,
top_p = args.top_p,
top_k = args.top_k,
do_sample = args.do_sample,
length_penalty = args.length_penalty,
max_new_tokens = args.max_new_tokens,
past_key_values=past_key_values,
return_past_key_values=True):
output = response[gen_len:]
print(output, end="", flush=True)
gen_len = len(response)
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument('--model_path', type=str, default=None, help="path to chat version model")
parser.add_argument('--tokenizer_path', type=str, default=None, help="path to chat version tokenizer")
parser.add_argument('--temperature', type=float, default=0.8, help="set temperature")
parser.add_argument('--top_p', type=float, default=0.95, help="set top p value")
parser.add_argument('--top_k', type=int, default=50, help="set top k value")
parser.add_argument('--do_sample', type=bool, default=True, help="whether turn on do_sample or not")
parser.add_argument('--length_penalty', type=float, default=1.2, help="set length penalty")
parser.add_argument('--max_new_tokens', type=int, default=512, help="set max new tokens")
args = parser.parse_args()
main(args)
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