Files
chatgpt-on-wechat/bot/openai/open_ai_session.py
2023-03-26 23:09:05 +08:00

77 lines
3.0 KiB
Python

from bot.session_manager import Session
from common.log import logger
class OpenAISession(Session):
def __init__(self, session_id, system_prompt=None, model= "text-davinci-003"):
super().__init__(session_id, system_prompt)
self.conversation = []
self.model = model
self.reset()
def reset(self):
pass
def add_query(self, query):
question = {'type': 'question', 'content': query}
self.conversation.append(question)
def add_reply(self, reply):
answer = {'type': 'answer', 'content': reply}
self.conversation.append(answer)
def __str__(self):
'''
e.g. Q: xxx
A: xxx
Q: xxx
'''
prompt = self.system_prompt
if prompt:
prompt += "<|endoftext|>\n\n\n"
for item in self.conversation:
if item['type'] == 'question':
prompt += "Q: " + item['content'] + "\n"
elif item['type'] == 'answer':
prompt += "\n\nA: " + item['content'] + "<|endoftext|>\n"
if len(self.conversation) > 0 and self.conversation[-1]['type'] == 'question':
prompt += "A: "
return prompt
def discard_exceeding(self, max_tokens, cur_tokens= None):
precise = True
try:
cur_tokens = num_tokens_from_string(str(self), self.model)
except Exception as e:
precise = False
if cur_tokens is None:
raise e
logger.debug("Exception when counting tokens precisely for query: {}".format(e))
while cur_tokens > max_tokens:
if len(self.conversation) > 1:
self.conversation.pop(0)
elif len(self.conversation) == 1 and self.conversation[0]["type"] == "answer":
self.conversation.pop(0)
if precise:
cur_tokens = num_tokens_from_string(str(self), self.model)
else:
cur_tokens = len(str(self))
break
elif len(self.conversation) == 1 and self.conversation[0]["type"] == "question":
logger.warn("user question exceed max_tokens. total_tokens={}".format(cur_tokens))
break
else:
logger.debug("max_tokens={}, total_tokens={}, len(conversation)={}".format(max_tokens, cur_tokens, len(self.conversation)))
break
if precise:
cur_tokens = num_tokens_from_string(str(self), self.model)
else:
cur_tokens = len(str(self))
return cur_tokens
# refer to https://github.com/openai/openai-cookbook/blob/main/examples/How_to_count_tokens_with_tiktoken.ipynb
def num_tokens_from_string(string: str, model: str) -> int:
"""Returns the number of tokens in a text string."""
import tiktoken
encoding = tiktoken.encoding_for_model(model)
num_tokens = len(encoding.encode(string,disallowed_special=()))
return num_tokens