Support Jinja syntax in templates

[wren]

Use Case/Motivation

We currently allow the use of a template file to seed a new entry. This file is currently a flat text file and is taken verbatim into the editor when creating a new entry.

It would be nice to (optionally) interpret this template file using some syntax (like Jinja) to add some functionality to these templates.

This would allow the use of Jinja syntax in these templates, which would allow things like using custom fields, or making loops in the template.

Example Usage

{# templates/some-other-template-to-include.jrnl #}

Hello {{ name }}! This is a template of some sort.

{% if my_field > 32 %}
Lorem ipsum dolor sit amet.
{% else %}
Also, lorem ipsum dolor sit amet.
{% endif %}

etc

Other Information

It should be a problem, but the ability to discard an entry if the template text didn't change merits some extra consideration with this new feature to make sure nothing breaks.

[micahellison]

I love this idea and I think Jinja is a good way to approach it.

I think the next question to figure out is: what custom fields should we support?

Some ideas:

• journal name
• any config value
• custom fields in config? perhaps under a template key in the config file
• fields passed in by command-line