Flask JSONEncoder将ensure_ascii设置为False [英] Flask JSONEncoder set ensure_ascii to False

问题描述

我正在一个小瓶子应用程序中，我想要返回包含变音符的字符串（通常是德语特殊字符，例如ß）。由于烧瓶中的$ code> JSONEncoder 的默认值为$ code> ensure_ascii = True ，这将永远转换我的字符串

I'm working on a small flask app in which I want to return strings containing umlauts (in general German special characters, e.g 'ß'). As the default JSONEncoder in flask has ensure_ascii=True, this will always convert my string

Hauptstraße 213

：

Hauptstra\u00dfe 213

我的第一种方法是创建一个非常基本的自定义 JSONEncoder

My first approach was to just create a very basic custom JSONEncoder

class NonAsciiJSONEncoder(json.JSONEncoder):
    def __init__(self, **kwargs):
        super(NonAsciiJSONEncoder, self).__init__(kwargs)
        self.ensure_ascii = False 

如果我使用这个，通过设置

If I use this, by setting

app.json_encoder = NonAsciiJSONEncoder

我的 return jsonify（...）将实际返回包含'ß'的字符串。

my return jsonify(...) will actually return the string containing 'ß'.

但是，由于 ensure_ascii 是默认编码器的属性，我认为只是更改它可能会更好通过将它设置为 False

However, as ensure_ascii is an attribute of the default Encoder, I thought it might be better to just change it by setting it to False

app.json_encoder.ensure_ascii = False

这将在返回之前将属性设置为False。但是不知何故，字符串仍然没有ß但是 \\\ß 返回。

This will actually set the property to False which I checked before returning. But somehow, the string is still returned without 'ß' but with \u00df.

正如我在自定义编码器中所做的一样，将这个属性设置为 False ？

How can this be, as all I'm doing in my custom Encoder, is setting this attribute to False?

推荐答案

更改 app.json_encoder时，您正在设置一个类属性。

JSONEncoder .__ init __ 方法将实例属性设置为 True ，因为 ensure_ascii 参数的默认值。设置类属性不会阻止 __ init __ 方法设置实例属性，它是在这里获得的实例属性。

The JSONEncoder.__init__ method sets an instance attribute to True, as that is the default value for the ensure_ascii argument. Setting the class attribute won't prevent the __init__ method from setting an instance attribute, and it is the instance attribute that wins here.

您可以让您的子类设置参数为 False ：

You could just have your subclass set the argument to False:

class NonASCIIJSONEncoder(json.JSONEncoder):
    def __init__(self, **kwargs):
        kwargs['ensure_ascii'] = False
        super(NonASCIIJSONEncoder, self).__init__(**kwargs)

这篇关于Flask JSONEncoder将ensure_ascii设置为False的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！