我有一些东西在设置。py,我想能够从模板访问,但我不知道如何做到这一点。我已经试过了

{{CONSTANT_NAME}}

但这似乎并不奏效。这可能吗?


当前回答

If we were to compare context vs. template tags on a single variable, then knowing the more efficient option could be benificial. However, you might be better off to dip into the settings only from templates that need that variable. In that case it doesn't make sense to pass the variable into all templates. But if you are sending the variable into a common template such as the base.html template, Then it would not matter as the base.html template is rendered on every request, so you can use either methods.

如果您决定使用template tags选项,那么使用下面的代码,因为它允许您传入一个默认值,以防有问题的变量未定义。

例如:get_from_settings my_variable as my_context_value

例如:get_from_settings my_variable my_default as my_context_value

class SettingsAttrNode(Node):
    def __init__(self, variable, default, as_value):
        self.variable = getattr(settings, variable, default)
        self.cxtname = as_value

    def render(self, context):
        context[self.cxtname] = self.variable
        return ''


def get_from_setting(parser, token):
    as_value = variable = default = ''
    bits = token.contents.split()
    if len(bits) == 4 and bits[2] == 'as':
        variable = bits[1]
        as_value = bits[3]
    elif len(bits) == 5 and bits[3] == 'as':
        variable     = bits[1]
        default  = bits[2]
        as_value = bits[4]
    else:
        raise TemplateSyntaxError, "usage: get_from_settings variable default as value " \
                "OR: get_from_settings variable as value"

    return SettingsAttrNode(variable=variable, default=default, as_value=as_value)

get_from_setting = register.tag(get_from_setting)

其他回答

Django提供了对模板中某些常用的设置常量的访问,比如settings。MEDIA_URL和一些语言设置,如果你使用django内置的通用视图或在render_to_response快捷函数中传入context实例关键字参数。以下是每种情况的示例:

from django.shortcuts import render_to_response
from django.template import RequestContext
from django.views.generic.simple import direct_to_template

def my_generic_view(request, template='my_template.html'):
    return direct_to_template(request, template)

def more_custom_view(request, template='my_template.html'):
    return render_to_response(template, {}, context_instance=RequestContext(request))

这些视图都有一些常用的设置,比如settings。模板可用的MEDIA_URL为{{MEDIA_URL}},等等。

如果你在设置中寻找对其他常量的访问,那么只需将你想要的常量解包,并将它们添加到你在视图函数中使用的上下文字典中,如下所示:

from django.conf import settings
from django.shortcuts import render_to_response

def my_view_function(request, template='my_template.html'):
    context = {'favorite_color': settings.FAVORITE_COLOR}
    return render_to_response(template, context)

现在你可以访问设置了。在模板中使用{{FAVORITE_COLOR}}。

上面来自bchhun的例子很好,只是你需要从settings.py显式地构建上下文字典。下面是一个未经测试的示例,说明如何从settings.py的所有大写属性(re: "^[A-Z0-9_]+$")自动构建上下文字典。

在settings.py的末尾:

_context = {} 
local_context = locals()
for (k,v) in local_context.items():
    if re.search('^[A-Z0-9_]+$',k):
        _context[k] = str(v)

def settings_context(context):
    return _context

TEMPLATE_CONTEXT_PROCESSORS = (
...
'myproject.settings.settings_context',
...
)

我发现最简单的方法是一个自定义模板标签:

from django import template
from django.conf import settings

register = template.Library()

# settings value
@register.simple_tag
def settings_value(name):
    return getattr(settings, name, "")

用法:

{% settings_value "LANGUAGE_CODE" %}

If we were to compare context vs. template tags on a single variable, then knowing the more efficient option could be benificial. However, you might be better off to dip into the settings only from templates that need that variable. In that case it doesn't make sense to pass the variable into all templates. But if you are sending the variable into a common template such as the base.html template, Then it would not matter as the base.html template is rendered on every request, so you can use either methods.

如果您决定使用template tags选项,那么使用下面的代码,因为它允许您传入一个默认值,以防有问题的变量未定义。

例如:get_from_settings my_variable as my_context_value

例如:get_from_settings my_variable my_default as my_context_value

class SettingsAttrNode(Node):
    def __init__(self, variable, default, as_value):
        self.variable = getattr(settings, variable, default)
        self.cxtname = as_value

    def render(self, context):
        context[self.cxtname] = self.variable
        return ''


def get_from_setting(parser, token):
    as_value = variable = default = ''
    bits = token.contents.split()
    if len(bits) == 4 and bits[2] == 'as':
        variable = bits[1]
        as_value = bits[3]
    elif len(bits) == 5 and bits[3] == 'as':
        variable     = bits[1]
        default  = bits[2]
        as_value = bits[4]
    else:
        raise TemplateSyntaxError, "usage: get_from_settings variable default as value " \
                "OR: get_from_settings variable as value"

    return SettingsAttrNode(variable=variable, default=default, as_value=as_value)

get_from_setting = register.tag(get_from_setting)

在Django 2.0+中添加了一个完整的创建自定义模板标签的答案

在你的app文件夹中,创建一个名为templatetags的文件夹。在其中,创建__init__.py和custom_tags.py:

在custom_tags.py中创建一个自定义标记函数,用于访问settings常量中的任意键:

from django import template
from django.conf import settings

register = template.Library()

@register.simple_tag
def get_setting(name):
    return getattr(settings, name, "")

要理解这段代码,我建议阅读Django文档中关于简单标记的部分。

然后,你需要在任何模板中加载这个文件,让Django知道这个(以及任何其他)自定义标记。就像你需要加载内置的静态标签一样:

{% load custom_tags %}

加载后,它可以像任何其他标签一样使用,只需提供您需要返回的特定设置。如果你有一个BUILD_VERSION变量在你的设置:

{% get_setting "BUILD_VERSION" %}

此解决方案不适用于数组,但如果需要,则可能需要在模板中放入太多逻辑。

注意:一个更清晰、更安全的解决方案可能是创建一个自定义上下文处理器,在其中添加所有模板可用的上下文所需的设置。这样可以降低在模板中错误地输出敏感设置的风险。