# Django 2.2.9.dev20191202104323 文档

# django.template.context_processors 源代码

    """
    A set of request processors that return dictionaries to be merged into a
    template context. Each function takes the request object as its only parameter
    and returns a dictionary to add to the context.

    These are referenced from the 'context_processors' option of the configuration
    of a DjangoTemplates backend and used by RequestContext.
    """

    import itertools

    from django.conf import settings
    from django.middleware.csrf import get_token
    from django.utils.functional import SimpleLazyObject, lazy

    def csrf(request):
        """
        Context processor that provides a CSRF token, or the string 'NOTPROVIDED' if
        it has not been provided by either a view decorator or the middleware
        """
        def _get_val():
            token = get_token(request)
            if token is None:
                # In order to be able to provide debugging info in the
                # case of misconfiguration, we use a sentinel value
                # instead of returning an empty dict.
                return 'NOTPROVIDED'
            else:
                return token

        return {'csrf_token': SimpleLazyObject(_get_val)}

    def debug(request):
        """
        Return context variables helpful for debugging.
        """
        context_extras = {}
        if settings.DEBUG and request.META.get('REMOTE_ADDR') in settings.INTERNAL_IPS:
            context_extras['debug'] = True
            from django.db import connections
            # Return a lazy reference that computes connection.queries on access,
            # to ensure it contains queries triggered after this function runs.
            context_extras['sql_queries'] = lazy(
                lambda: list(itertools.chain.from_iterable(connections[x].queries for x in connections)),
                list
            )
        return context_extras

    def i18n(request):
        from django.utils import translation
        return {
            'LANGUAGES': settings.LANGUAGES,
            'LANGUAGE_CODE': translation.get_language(),
            'LANGUAGE_BIDI': translation.get_language_bidi(),
        }

    def tz(request):
        from django.utils import timezone
        return {'TIME_ZONE': timezone.get_current_timezone_name()}

    def static(request):
        """
        Add static-related context variables to the context.
        """
        return {'STATIC_URL': settings.STATIC_URL}

    def media(request):
        """
        Add media-related context variables to the context.
        """
        return {'MEDIA_URL': settings.MEDIA_URL}

    def request(request):
        return {'request': request}