How to load jinja template directly from filesystem

Here's how: use a FileSystemLoader instead of a PackageLoader. I found examples on the web here and here. Let's say you have a python file in the same dir as your template:

./index.py./template.html

This index.py will find the template and render it:

#!/usr/bin/pythonimport jinja2templateLoader = jinja2.FileSystemLoader(searchpath="./")templateEnv = jinja2.Environment(loader=templateLoader)TEMPLATE_FILE = "template.html"template = templateEnv.get_template(TEMPLATE_FILE)outputText = template.render()  # this is where to put args to the template rendererprint(outputText)

It turns out, the jinja2 API doc does have a section which discusses all the built-in loaders, so it's kind of embarrassing not to have noticed that right away. But the introduction is worded such that PackageLoader seems to be the default, "simplest" method. For newcomers to python, this can lead to a wild goose chase.

A simpler way is to directly call the jinj2.Template constructor and use open to load the file:

from jinja2 import Templatewith open('template.html.jinja2') as file_:    template = Template(file_.read())template.render(name='John')

Here is the one liner:

template = Template(open('template_file.j2').read())

Then you can render the template on another line, or for all in one line:

rendered = Template(open('template_file.j2').read()).render(var="TEXT")