Jinja2 Syntax Notes ========================== 1. Variables --------------------- .. code:: {{ EXPRESSION }} 2. Conditionals --------------------- .. code:: {% if EXPRESSION %} ... {% elif EXPRESSION %} ... {% else %} ... {% endif %} 3. Loops -------------------- .. code:: {% for item in items %} ...{{ item }}... {% endfor %} Loop special variables: {{ loop.index }} {# 1-based #} {{ loop.index0 }} {# 0-based #} {{ loop.first }} {{ loop.last }} 4. Template Inheritance ------------------------------- .. code:: {% block block_name %}{% endblock %} {% extends "extended_template_name" %} .. code:: #Example: #layout.html

Site Header

{% block content %}{% endblock %} #webpage.thml {% extends "layout.html" %} {% block content %}

This is the page content.

{% endblock %} 5. Including Templates ---------------------------- .. code:: {% include "included_file_name.html" %} 6. Macros ------------------ .. code:: {% macro button(text, type="primary") %} {% endmacro %} {{ button("Save") }} {{ button("Delete", "danger") }} 7. Importing Macros -------------------------- .. code:: {% import "macros.html" as ui %} {{ ui.button("Click me") }} 8. Filters ------------------ .. code:: {{ name | upper }} {{ text | replace("old", "new") }} {{ items | length }} {{ content | safe }} {# do not escape HTML #} Common filters: upper, lower title length replace("a","b") join(", ") safe (disable autoescape) default("value") .. image:: ./jinja2-builtin-filters.png :width: 98% 9. Set Variables in Template ------------------------------------- .. code:: {% set total = price * quantity %}

Total: {{ total }}

10. Raw Blocks --------------------- .. code:: {% raw %} {{ this_will_not_be_rendered }} {% endraw %} 11. Comments ------------------------------ .. code:: {# This is a comment and will not appear in output #} --------------------------------------------------- An jinja2 API example -------------------------- .. code:: python import jinja2 env = jinja2.Environment(loader=jinja2.FileSystemLoader("./templates")) temp = env.get_template("content.html") html = temp.render(add_block2=True, title="

Test

") print(html) ---------------------------------------------------- References ------------------- https://jinja.palletsprojects.com/en/stable/templates/ https://jinja.palletsprojects.com/en/stable/api/