jinja2loader.py

"""
Based on
http://www.bitbucket.org/mitsuhiko/jinja2-main/src/tip/ext/djangojinja2.py
"""
import jinja2

from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.template import TemplateDoesNotExist
from django.template.loader import BaseLoader

class Template(jinja2.Template):

    def render(self, context):
        """Flatten the Django Context object and calls Jinja's render"""
        context_dict = {}
        for d in context.dicts:
            context_dict.update(d)
        return super(Template, self).render(context_dict)


class Loader(BaseLoader):
    is_usable = True

    def __init__(self, *args, **kwargs):
        super(Loader, self).__init__(*args, **kwargs)

        try:
            searchpath = list(settings.JINJA2_TEMPLATE_DIRS)
        except AttributeError:
            raise ImproperlyConfigured("Please fill out JINJA2_TEMPLATE_DIRS "
                                       "in the settings module before using "
                                       "this Jinja2 template loader")

        self.env = jinja2.Environment(loader=jinja2.FileSystemLoader(searchpath),
                               auto_reload=settings.TEMPLATE_DEBUG,
                               cache_size=getattr(settings, 'JINJA2_CACHE_SIZE', 50),
                               extensions=getattr(settings, 'JINJA2_EXTENSIONS', ()),
                              )
        # use our custom Template class in this environment
        self.env.template_class = Template

    def load_template(self, template_name, template_dirs=None):
        try:
            # @@@: and template_dirs?
            return self.env.get_template(template_name), None
        except jinja2.TemplateNotFound, e:
            raise TemplateDoesNotExist(str(e))