jinja_cli.py

"""Run this file like this:

>>> python jinja_cli.py path/to/my/file.txt --foo bar

and it will render the file as a Jinja template with foo="bar".
"""
import os
import click  # pip install click
import jinja2  # pip install jinja2

JINJA_DIRECTORY = os.path.dirname(__file__)

jinja_env = jinja2.Environment(
    loader=jinja2.FileSystemLoader(JINJA_DIRECTORY)
)


@click.command(context_settings=dict(
    ignore_unknown_options=True,
    allow_extra_args=True
))
@click.argument('filename', type=click.Path(exists=True))
@click.pass_context
def generate_markup(ctx: click.Context, filename: str):
    """Markup a file with Jinja and print the results.

    This command accepts arbitrary args that start with two dashes, e.g.
    `--foo bar` passes foo="bar" into the Jinja template.
    """
    # Parse extra options
    iterargs = iter(ctx.args)
    kwargs = {k[2:]: v for k, v in zip(iterargs, iterargs)}
    # render template
    res = jinja_env.get_template(filename).render(**kwargs)
    # print the file into the terminal
    click.echo(res)


if __name__ == '__main__':
    generate_markup()