Регистратор блокирует файл журнала. Невозможно создать новый файл журнала

Question

Я использую регистратор TimedRotatingFileHandler в моем приложении flask. Когда HTTP-запрос отправляется приложению в первый раз, код выполняется и успешно создает файл журнала APIlog.log. Когда отправляется второй HTTP-запрос, выполняется тот же фрагмент кода, и я получаю исключение об использовании файла журнала другим процессом.

Ниже выдается исключение:

--- Logging error ---
Traceback (most recent call last):
  File "C:\Program Files (x86)\Python 3.5\lib\logging\handlers.py", line 72, in emit
    self.doRollover()
  File "C:\Program Files (x86)\Python 3.5\lib\logging\handlers.py", line 393, in doRollover
    self.rotate(self.baseFilename, dfn)
  File "C:\Program Files (x86)\Python 3.5\lib\logging\handlers.py", line 113, in rotate
    os.rename(source, dest)
PermissionError: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\ProjectFiles\\ExceptionLogFiles\\APIlog' -> 'C:\\ProjectFiles\\ExceptionLogFiles\\APIlog.2020_02_06.log'
Call stack:
  File "C:\Program Files (x86)\Python 3.5\lib\threading.py", line 891, in _bootstrap
    self._bootstrap_inner()
  File "C:\Program Files (x86)\Python 3.5\lib\threading.py", line 923, in _bootstrap_inner
    self.run()
  File "C:\Program Files (x86)\Python 3.5\lib\threading.py", line 871, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Program Files (x86)\Python 3.5\lib\socketserver.py", line 628, in process_request_thread
    self.finish_request(request, client_address)
  File "C:\Program Files (x86)\Python 3.5\lib\socketserver.py", line 357, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "C:\Program Files (x86)\Python 3.5\lib\socketserver.py", line 684, in __init__
    self.handle()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\werkzeug\serving.py", line 327, in handle
    rv = BaseHTTPRequestHandler.handle(self)
  File "C:\Program Files (x86)\Python 3.5\lib\http\server.py", line 415, in handle
    self.handle_one_request()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\werkzeug\serving.py", line 362, in handle_one_request
    return self.run_wsgi()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\werkzeug\serving.py", line 304, in run_wsgi
    execute(self.server.app)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\werkzeug\serving.py", line 294, in execute
    for data in application_iter:
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\werkzeug\debug\__init__.py", line 330, in debug_application
    app_iter = self.app(environ, start_response)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2463, in __call__
    return self.wsgi_app(environ, start_response)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2446, in wsgi_app
    response = self.full_dispatch_request()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 1949, in full_dispatch_request
    rv = self.dispatch_request()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 1935, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "C:\plugin\ferc\api\api.py", line 30, in validate
    app.logger.debug("New : CID: {}, Period:{}, Year:{}, FileName:{}".format(cid,period,year,filename))
Message: 'New : CID: C00123, Period:Q4, Year:2016, FileName:TEST.doc'
Arguments: ()
127.0.0.1 - - [06/Feb/2020 16:26:34] "POST /validate HTTP/1.1" 500 -
Traceback (most recent call last):
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2463, in __call__
    return self.wsgi_app(environ, start_response)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2449, in wsgi_app
    response = self.handle_exception(e)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask_restful\__init__.py", line 269, in error_router
    return original_handler(e)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 1866, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\_compat.py", line 39, in reraise
    raise value
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2446, in wsgi_app
    response = self.full_dispatch_request()
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 1952, in full_dispatch_request
    return self.finalize_request(rv)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 1967, in finalize_request
    response = self.make_response(rv)
  File "C:\Program Files (x86)\Python 3.5\lib\site-packages\flask\app.py", line 2097, in make_response
    "The view function did not return a valid response. The"
TypeError: The view function did not return a valid response. The function either returned None or ended without a return statement.

Ниже приведен мой код:

from flask import Flask, request, jsonify
from flask_restful import Resource, Api
from sqlalchemy import create_engine
from json import dumps
from flask_jsonpify import jsonify
import subprocess
from subprocess import check_output
from datetime import datetime
import os
import configparser
import adodbapi
import logging
from logging.handlers import TimedRotatingFileHandler
from collections import OrderedDict
from logging.handlers import RotatingFileHandler

app = Flask(__name__)
api = Api(app)

@app.route('/validate', methods=['POST'])
def validate():
    try:

        date =  datetime.now().strftime('%Y_%m_%d_%H-%M-%S')
        cid = request.form.get("cid")
        period = request.form.get("period")
        year = request.form.get("year")
        form = request.form.get("form")
        filename = request.files.get("file").filename        
        app.logger.debug("New : CID: {}, Period:{}, Year:{}, FileName:{}".format(cid,period,year,filename))


    except Exception as e:
        app.logger.exception("validate function: Something went wrong. ", exc_info=True)
        return '"INVALID FILE"'


if __name__ == '__main__':
    app.debug = True
    logFilePath = "C:/ProjectFiles/ExceptionLogFiles/"
    logger = logging.getLogger('APIlogger')
    logger.setLevel(logging.DEBUG)
    formatter = logging.Formatter(fmt='%(asctime)s %(levelname)-5s %(message)s', datefmt='%m-%d-%y %H:%M:%S')
    #fh = TimedRotatingFileHandler(logFilePath + 'APIlog',when='midnight')
    fh = TimedRotatingFileHandler(logFilePath + 'APIlog',when = 's', interval = 30, backupCount = 20)
    fh.suffix = "%Y_%m_%d.log"
    fh.setFormatter(formatter)    
    app.logger.addHandler(fh)
    app.run(host="0.0.0.0", port='80')

Пожалуйста, кто-нибудь может помочь мне решить эту проблему блокировки.