Flask实现异步调用sqlalchemy的模型类

事情是这样的，我这边需要在一次请求里面，搞一个异步不阻碍的任务，来执行耗时的操作。
一开始，我准备写的代码是这样的：

from flask import Flask
import time
from concurrent.futures import ThreadPoolExecutor

executor = ThreadPoolExecutor(1)

app = Flask(__name__)


@app.route('/synchronize')
def update_redis():
    executor.submit(do_update)
    return 'ok'


def do_update():
    time.sleep(3)
    print('start update')


if __name__ == '__main__':
    app.run()

但是，异步函数里面没有app的上下文，没办法调用sqlalchemy模型类、config内容、logger等。
所以，我封装成了一个接口，异步只负责发起耗时请求，这样就可以在耗时请求TtsCopyVoiceRaw里面正常使用app上下文了：

# 复制音色 异步
class TtsCopyVoiceRaw(Resource):
    def post(self):
        user_id = request.json.get('user_id')
        name = request.json.get('name')
        speed = request.json.get('speed', 0.75)
        audio_url = request.json.get('audio_url')
        current_app.logger.info('copy_voice 1 --------------')
        current_app.logger.info(user_id, name, audio_url, speed)
        try:
            voice_id = TTSApi().copy_voice(user_id, name, audio_url, speed)
            audition_url = TTSApi().tts(
            	user_id, '欢迎使用直播助手，我是{}'.format(name), voice_id, speed)
            current_app.logger.info('copy_voice voice_id --------------')
            current_app.logger.info(voice_id)
            voice_obj = db.session.query(UserTimbre).filter(
                UserTimbre.user_id == user_id,
                UserTimbre.name == name,
            ).first()
            voice_obj.voice_id = voice_id
            voice_obj.audition_url = audition_url
            voice_obj.status = 3
            db.session.commit()
        except Exception as e:
            current_app.logger.info('copy_voice failed --------------')
            current_app.logger.info(traceback.format_exc())
            voice_obj = db.session.query(UserTimbre).filter(
                UserTimbre.user_id == user_id,
                UserTimbre.name == name,
            ).first()
            voice_obj.status = 4
            db.session.commit()

def copy_voice(full_path, user_id, name, audio_url, speed):
    print('copy_voice -----------')
    print(full_path, user_id, name, audio_url, speed)
    requests.post(full_path + '/raw', json=dict(
        user_id=user_id,
        name=name,
        audio_url=audio_url,
        speed=speed,
    ))


# 复制音色
class TtsCopyVoice(ResourceApiPassed):
    def post(self):
        user_id = self.user_info.get('id')
        name = request.json.get('name')
        speed = request.json.get('speed', 0.75)
        audio_url = request.json.get('audio_url')

        total = db.session.query(UserTimbre).filter(
            UserTimbre.user_id == user_id,
            UserTimbre.name == name,
        ).count()
        if total:
            raise APIException('名称已存在，请改名重新创建')

        current_app.logger.warn('TtsCopyVoice ******* 1')
        current_app.logger.warn(user_id)
        current_app.logger.warn(name)
        current_app.logger.warn(speed)
        current_app.logger.warn(audio_url)

        try:
            current_app.logger.warn('obj ------------- 0')
            # 创建 用户音色
            obj = UserTimbre(
                user_id = user_id,
                name = name,
                status = 1,
            )
            db.session.add(obj)
            db.session.commit()
        except Exception as e:
            current_app.logger.warn('e ------------- 0')
            current_app.logger.warn(e)
            current_app.logger.warn('e ------------- 1')
            current_app.logger.warn(traceback.format_exc())
            raise APIException('创建失败')
        current_app.executor.submit(
        	copy_voice, request.url, user_id, name, audio_url, speed)
        return success({'id': obj.id})