local-llm-server/llm_server/routes/openai/chat_completions.py

126 lines
5.8 KiB
Python

import json
import time
import traceback
from flask import Response, jsonify, request
from llm_server.custom_redis import redis
from . import openai_bp
from ..helpers.http import validate_json
from ..openai_request_handler import OpenAIRequestHandler
from ... import opts
from ...database.database import log_prompt
from ...llm.generator import generator
from ...llm.openai.oai_to_vllm import oai_to_vllm
from ...llm.openai.transform import generate_oai_string, transform_messages_to_prompt, trim_messages_to_fit
# TODO: add rate-limit headers?
@openai_bp.route('/chat/completions', methods=['POST'])
def openai_chat_completions():
request_valid_json, request_json_body = validate_json(request)
if not request_valid_json or not request_json_body.get('messages') or not request_json_body.get('model'):
return jsonify({'code': 400, 'msg': 'invalid JSON'}), 400
else:
handler = OpenAIRequestHandler(incoming_request=request, incoming_json=request_json_body)
if handler.cluster_backend_info['mode'] != 'vllm':
# TODO: implement other backends
raise NotImplementedError
if not request_json_body.get('stream'):
try:
return handler.handle_request()
except Exception:
traceback.print_exc()
return 'Internal server error', 500
else:
if not opts.enable_streaming:
# TODO: return a proper OAI error message
return 'disabled', 401
if opts.openai_silent_trim:
handler.request_json_body['messages'] = trim_messages_to_fit(request_json_body['messages'], handler.cluster_backend_info['model_config']['max_position_embeddings'], handler.backend_url)
response_status_code = 0
start_time = time.time()
request_valid, invalid_response = handler.validate_request()
if not request_valid:
return invalid_response
else:
if opts.openai_silent_trim:
oai_messages = trim_messages_to_fit(handler.request.json['messages'], handler.cluster_backend_info['model_config']['max_position_embeddings'], handler.backend_url)
else:
oai_messages = handler.request.json['messages']
handler.prompt = transform_messages_to_prompt(oai_messages)
handler.parameters = oai_to_vllm(handler.parameters, hashes=True, mode=handler.cluster_backend_info['mode'])
msg_to_backend = {
**handler.parameters,
'prompt': handler.prompt,
'stream': True,
}
try:
response = generator(msg_to_backend, handler.backend_url)
r_headers = dict(request.headers)
r_url = request.url
model = redis.get('running_model', 'ERROR', dtype=str) if opts.openai_expose_our_model else request_json_body.get('model')
oai_string = generate_oai_string(30)
def generate():
generated_text = ''
partial_response = b''
for chunk in response.iter_content(chunk_size=1):
partial_response += chunk
if partial_response.endswith(b'\x00'):
json_strs = partial_response.split(b'\x00')
for json_str in json_strs:
if json_str:
try:
json_obj = json.loads(json_str.decode())
new = json_obj['text'][0].split(handler.prompt + generated_text)[1]
generated_text = generated_text + new
except IndexError:
# ????
continue
data = {
"id": f"chatcmpl-{oai_string}",
"object": "chat.completion.chunk",
"created": int(time.time()),
"model": model,
"choices": [
{
"index": 0,
"delta": {
"content": new
},
"finish_reason": None
}
]
}
yield f'data: {json.dumps(data)}\n\n'
yield 'data: [DONE]\n\n'
end_time = time.time()
elapsed_time = end_time - start_time
log_prompt(
handler.client_ip,
handler.token,
handler.prompt,
generated_text,
elapsed_time,
handler.parameters,
r_headers,
response_status_code,
r_url,
handler.backend_url,
)
return Response(generate(), mimetype='text/event-stream')
except:
# TODO: simulate OAI here
raise Exception