Question

The Flask docs state:

autoescaping is enabled for all templates ending in .html, .htm, .xml as well as .xhtml

How do I enable autoescaping for templates ending with a .jhtml extension?

Answer 1

Thanks to @Cagez’s answer I was able to come up with a robust (and recommended) solution.

According to a post on the Flask mailing list, the way to do this is to override flask.Flask.select_jinja_autoescape(). The linked snippet in that post demonstrating how to override which templates are autoescaped didn’t quite work, so I came up with the following, which does work:

class JHtmlEscapingFlask(Flask):

    def select_jinja_autoescape(self, filename):
        if filename is None:
            return False
        if filename.endswith('.jhtml'):
            return True
        return Flask.select_jinja_autoescape(self, filename)

app = JHtmlEscapingFlask(__name__)

I put this at the top of my main Flask app file, replacing the usual app = Flask(__name__)