Write your own template engine

Like all other parts of Django Chuck even the template engine can be customized. For the first version we tried to use Cheetah and Mako, but both didn’t really fit our needs so we implemented our own template engine. Nevertheless both old engines still exist and you can use them to write your Chuck templates. Of course you will have to rewrite all modules if you switch the template engine. They cannot be mixed.

Using either Cheetah or Mako is as easy as setting a config value.

template_engine="django_chuck.template.mako_engine"

You don’t like all three and want to implement another one or even your own? No problem! Just create a module in django_chuck.template, let it inherit from BaseEngine and implement the handle function that gets called with the name of each file in each module, it’s output filename in the site directory and a placeholder dictionary containing all variables and their values.

All the handle function now has to do is read the input_file, render the template stuff in it by using the placeholder dictionary and write it to the output_file.

Here’s the implementation of the Cheetah engine as an example:

from django_chuck.template.base import BaseEngine
from django_chuck.utils import write_to_file
from Cheetah.Template import Template

class TemplateEngine(BaseEngine):
    def handle(self, input_file, output_file, placeholder):
        with open(input_file, "rb") as f:
            write_to_file(output_file, f.read())

        template = str(Template(output_file, searchList=[placeholder]))

        with open(input_file, "w") as f:
            f.write(template)