出现错误“调用 Python 对象时超出最大递归深度”

Question

所以我刚刚收到一个错误，我有点不明白是什么原因。

Traceback (most recent call last):
  File "C:\Users\utils.py", line 657, in script
    logger.warn('Wopsiy! No word found!')
  File "C:\Users\utils.py", line 30, in warn
    sys.stdout.write("{}{} {}".format(self.__timestamp(), '[' + self.name + '] -', colored(text, "yellow")))
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 40, in write
    self.__convertor.write(text)
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 141, in write
    self.write_and_convert(text)
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 166, in write_and_convert
    self.write_plain_text(text, cursor, start)
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 174, in write_plain_text
    self.wrapped.write(text[start:end])
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 40, in write
    self.__convertor.write(text)
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 141, in write
    self.write_and_convert(text)
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 169, in write_and_convert
    self.write_plain_text(text, cursor, len(text))
  File "C:\Program Files\Python36\lib\site-packages\colorama\ansitowin32.py", line 174, in write_plain_text
    self.wrapped.write(text[start:end])

我可以看到它与我自己创建的记录器有一些类似的东西：

实用程序类

from datetime import datetime
from termcolor import cprint, colored
import sys

import colorama

class Logger:

    def __init__(self,name):
        colorama.init()
        self.name = name

    @staticmethod
    def __timestamp():
        timestamp = str(datetime.now().strftime("[%H:%M:%S.%f")[:-3]+"]")
        return timestamp

    def warn(self, text):
        sys.stdout.write("{}{} {}".format(self.__timestamp(), '[' + self.name + '] -', colored(text, "yellow")))
        sys.stdout.write("\n")
        sys.stdout.flush()

基本上我也做了一个简单的代码来说明我的代码是什么样的：

from utils import Logger
logger = Logger('Script')

def main():
    logger = Logger("product_info")
    word = ['Nope', 'There', 'Is', 'No', 'Word']
    while True:

        try:

            for _ in infinity():
                 if 'Hello' in word:
                     print('WORKS!!')

            else:
                logger.warn('Wopsiy! No word found!')
                time.sleep(1)

         except Exception as err:
              print(err)
              time.sleep(1)
              continue

所以问题是，过了一会儿它给了我maximum recursion depth exceeded while calling a Python object 的错误，但我只有在打印出except Exception as err: 时才会得到它，但是当我通过控制台查看时，它会给我顶部给出的输出.

现在的问题是，我实际上不知道它的原因是什么。

编辑

from datetime import datetime
from termcolor import cprint, colored
import sys

import colorama
colorama.init()
class Logger:

    def __init__(self,name):
        self.name = name

    @staticmethod
    def __timestamp():
        timestamp = str(datetime.now().strftime("[%H:%M:%S.%f")[:-3]+"]")
        return timestamp

    def warn(self, text):
        sys.stdout.write("{}{} {}".format(self.__timestamp(), '[' + self.name + '] -', colored(text, "yellow")))
        sys.stdout.write("\n")
        sys.stdout.flush()

Answer 1

正如我从 cmets 中对问题的讨论中了解到的那样，您可以在执行脚本期间创建 Logger 类的多个实例。 Logger 的每次创建都会调用 colorama.init()。每次调用 colorama.init() 都会强制 Colorama 将 sys.stdout 和 sys.stderr 流替换为它们的 colorama 包装版本。

在越来越多地调用colorama.init 之后，您的流变成了许多（无用重复的）colorama 包装层的肥洋葱，并且对print 的单个调用必须逐层递归传递，直到它到达实际sys.stdout。

当层数超过允许的最大堆栈深度时，您会遇到异常。 this open colorama issue中也提到了这种情况。

解决问题的最简单方法是将colorama.init() 移出Logger 构造函数，并在全局范围内使用类似的东西：

import colorama
colorama.init()