local-llm-server/llm_server/routes/request_handler.py

import sqlite3
import time
from typing import Union

from flask import jsonify

from llm_server import opts
from llm_server.database import log_prompt
from llm_server.llm.hf_textgen.hf_textgen_backend import HfTextgenLLMBackend
from llm_server.llm.oobabooga.ooba_backend import OobaboogaLLMBackend
from llm_server.llm.vllm.vllm_backend import VLLMBackend
from llm_server.routes.cache import redis
from llm_server.routes.helpers.client import format_sillytavern_err
from llm_server.routes.helpers.http import validate_json
from llm_server.routes.queue import priority_queue
from llm_server.routes.stats import SemaphoreCheckerThread

DEFAULT_PRIORITY = 9999


def delete_dict_key(d: dict, k: Union[str, list]):
    if isinstance(k, str):
        if k in d.keys():
            del d[k]
    elif isinstance(k, list):
        for item in k:
            if item in d.keys():
                del d[item]
    else:
        raise ValueError
    return d


class OobaRequestHandler:
    def __init__(self, incoming_request):
        self.request_json_body = None
        self.request = incoming_request
        self.start_time = time.time()
        self.client_ip = self.get_client_ip()
        self.token = self.request.headers.get('X-Api-Key')
        self.parameters = self.get_parameters()
        self.priority = self.get_priority()
        self.backend = self.get_backend()

    def validate_request(self) -> (bool, Union[str, None]):
        # TODO: move this to LLMBackend
        if self.parameters.get('max_new_tokens', 0) > opts.max_new_tokens or self.parameters.get('max_tokens', 0) > opts.max_new_tokens:
            return False, f'`max_new_tokens` must be less than or equal to {opts.max_new_tokens}'
        return True, None

    def get_client_ip(self):
        if self.request.headers.get('cf-connecting-ip'):
            return self.request.headers.get('cf-connecting-ip')
        elif self.request.headers.get('x-forwarded-for'):
            return self.request.headers.get('x-forwarded-for').split(',')[0]
        else:
            return self.request.remote_addr

    def get_parameters(self):
        # TODO: make this a LLMBackend method
        request_valid_json, self.request_json_body = validate_json(self.request.data)
        if not request_valid_json:
            return jsonify({'code': 400, 'msg': 'Invalid JSON'}), 400
        parameters = self.request_json_body.copy()
        if opts.mode in ['oobabooga', 'hf-textgen']:
            del parameters['prompt']
        elif opts.mode == 'vllm':
            parameters = delete_dict_key(parameters, ['messages', 'model', 'stream', 'logit_bias'])
        else:
            raise Exception
        return parameters

    def get_priority(self):
        if self.token:
            conn = sqlite3.connect(opts.database_path)
            cursor = conn.cursor()
            cursor.execute("SELECT priority FROM token_auth WHERE token = ?", (self.token,))
            result = cursor.fetchone()
            conn.close()
            if result:
                return result[0]
        return DEFAULT_PRIORITY

    def get_backend(self):
        if opts.mode == 'oobabooga':
            return OobaboogaLLMBackend()
        elif opts.mode == 'hf-textgen':
            return HfTextgenLLMBackend()
        elif opts.mode == 'vllm':
            return VLLMBackend()
        else:
            raise Exception

    def handle_request(self):
        SemaphoreCheckerThread.recent_prompters[self.client_ip] = time.time()

        # Fix bug on text-generation-inference
        # https://github.com/huggingface/text-generation-inference/issues/929
        if opts.mode == 'hf-textgen' and self.parameters.get('typical_p', 0) > 0.998:
            self.request_json_body['typical_p'] = 0.998

        if opts.mode == 'vllm':
            full_model_path = redis.get('full_model_path')
            if not full_model_path:
                raise Exception
            self.request_json_body['model'] = full_model_path.decode()

        request_valid, invalid_request_err_msg = self.validate_request()
        params_valid, invalid_params_err_msg = self.backend.validate_params(self.parameters)
        if not request_valid or not params_valid:
            error_messages = [msg for valid, msg in [(request_valid, invalid_request_err_msg), (params_valid, invalid_params_err_msg)] if not valid]
            combined_error_message = ', '.join(error_messages)
            err = format_sillytavern_err(f'Validation Error: {combined_error_message}.', 'error')
            log_prompt(self.client_ip, self.token, self.request_json_body.get('prompt', ''), err, 0, self.parameters, dict(self.request.headers), 0, is_error=True)
            # TODO: add a method to LLMBackend to return a formatted response string, since we have both Ooba and OpenAI response types
            return jsonify({
                'code': 400,
                'msg': 'parameter validation error',
                'results': [{'text': err}]
            }), 200

        queued_ip_count = redis.get_dict('queued_ip_count').get(self.client_ip, 0) + redis.get_dict('processing_ips').get(self.client_ip, 0)
        if queued_ip_count < opts.simultaneous_requests_per_ip or self.priority == 0:
            event = priority_queue.put((self.request_json_body, self.client_ip, self.token, self.parameters), self.priority)
        else:
            # Client was rate limited
            event = None

        if not event:
            return self.handle_ratelimited()
        event.wait()
        success, response, error_msg = event.data

        end_time = time.time()
        elapsed_time = end_time - self.start_time
        return self.backend.handle_response(success, response, error_msg, self.client_ip, self.token, self.request_json_body.get('prompt', ''), elapsed_time, self.parameters, dict(self.request.headers))

    def handle_ratelimited(self):
        backend_response = format_sillytavern_err(f'Ratelimited: you are only allowed to have {opts.simultaneous_requests_per_ip} simultaneous requests at a time. Please complete your other requests before sending another.', 'error')
        log_prompt(self.client_ip, self.token, self.request_json_body.get('prompt', ''), backend_response, None, self.parameters, dict(self.request.headers), 429, is_error=True)
        return jsonify({
            'results': [{'text': backend_response}]
        }), 200