Persist UTF-8 as Default Encoding

Question

I tried to persist UTF-8 as the default encoding in Python.

I tried:

>>> import sys
>>> sys.getdefaultencoding()
'ascii'

And I also tried:

>>> import sys
>>> reload(sys)
<module 'sys' (built-in)>
>>> sys.setdefaultencoding('UTF8')
>>> sys.getdefaultencoding()
'UTF8'
>>> 

But after closing the session and opening a new session, the following was the result:

>>> import sys
>>> sys.getdefaultencoding()
'ascii'

How can I persist my changes? (I know that it's not always a good idea to change to UTF-8. It's in a Docker container of Python).

I know it's possible. I saw someone who has UTF-8 as his default encoding (always).

Answer 1

首先，这几乎肯定是一个坏主意，因为如果您在尚未完成此配置的另一台机器上运行代码，代码将会神秘地中断。

(1) 创建一个像这样的新文件（我的名为setEncoding.py）：

import sys
# reload because Python removes setdefaultencoding() from the namespace
# see http://stackoverflow.com/questions/2276200/changing-default-encoding-of-python
reload(sys)
sys.setdefaultencoding("utf-8")

(2) 设置环境变量[PYTHONSTARTUP][1]指向该文件。

PYTHONSTARTUP(3) 当Python解释器加载时，首先执行指向的文件内的代码：

bgporter@Ornette ~/temp:python
Python 2.7.10 (default, Oct 23 2015, 19:19:21)
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> sys.getdefaultencoding()
'utf-8'
>>>

Answer 2

请查看site.py库 - 这是发生的地方sys.setdefaultencoding。我认为，您可以修改或替换此模块，以便使其永久保留在您的计算机上。这是它的一些源代码，注释解释了一些内容：

def setencoding():
    """Set the string encoding used by the Unicode implementation.  The
    default is 'ascii', but if you're willing to experiment, you can
    change this."""

    encoding = "ascii" # Default value set by _PyUnicode_Init()
    if 0:
        # Enable to support locale aware default string encodings.
        import locale
        loc = locale.getdefaultlocale()
        if loc[1]:
            encoding = loc[1]
    if 0:
        # Enable to switch off string to Unicode coercion and implicit
        # Unicode to string conversion.
        encoding = "undefined"
    if encoding != "ascii":
        # On Non-Unicode builds this will raise an AttributeError...
        sys.setdefaultencoding(encoding) # Needs Python Unicode build !

完整源代码https://hg.python.org/cpython/file/2.7/Lib/site.py。

sys.setdefaultencoding如果您想知道，这是他们删除该函数的地方：

def main():

    ...

    # Remove sys.setdefaultencoding() so that users cannot change the
    # encoding after initialization.  The test for presence is needed when
    # this module is run as a script, because this code is executed twice.
    if hasattr(sys, "setdefaultencoding"):
        del sys.setdefaultencoding