Django i18n translating text with html

Question

What to do with HTML in translations? I want to translate sentences with HTML in them. For example such a string ([login] is a link):

Please [login] to view your profile.

I do not want to bother my translators with translating text with html intertwined. On the other hand, I do not want to bother with creating all the links in my views, like suggested in this question. So ideally I want a template-only solution to have the flexibility of crafting HTML, while allowing translators to only work with text strings.

For example, this pseudocode implements these requirements:

{% render as login_html %}
    <a href="{{ url 'login' }}?next={{ request.path|urlencode }}">
        {% trans "Login" %}
    </a>
{% endrender %}

{% blocktrans with login=login_html %}
    Please {{ login }} to view your profile.
{% endblocktrans %}

First, the login HTML is rendered and stored as login_url. Then in my blocktrans, I can simply use {{ login }} to give the rendered login HTML. Is there a (similar) solution to this problem, or would it require custom template tags?

Answer 1

I've created a generic render tag to do just that:

from classytags.arguments import Argument, Flag
from classytags.core import Options
from classytags.helpers import AsTag
from django import template
from django.utils.safestring import mark_safe

register = template.Library()


class Render(AsTag):
    """
    Renders the block contents to be used elsewhere in the template.

    Example usage:

        {% render as login_url %}
            <a href="{% url 'login' %}">{% trans "Login" %}</a>
        {% endrender %}

        {% blocktrans %}
            Please {{ login_url }} for more information.
        {% endblocktrans %}

    It will automatically strip leading and trailing whitespace, use `nowrap`
    to disable this behaviour:

        {% render nostrip as varname %} . . . {% endrender %}
    """
    options = Options(
        Flag('strip', default=True, false_values=['nostrip']),
        'as',
        Argument('varname', resolve=False, required=True),
        blocks=[('endrender', 'nodelist')],
    )

    def get_value(self, context, nodelist, strip, **kwargs):
        value = nodelist.render(context)
        if strip:
            value = value.strip()
        return mark_safe(value)
register.tag(Render)

When used with translation contexts (e.g. {% trans "Login" context "login_url" %}), the translator will have great control over the translation while still not being bothered with HTML.

msgctxt "login_url"
msgid "Login"
msgstr ""

#, python-format
msgid "Please %(login_url)s for more information."
msgstr ""