jcorpac Flask Templating (Jinja2)
The front-end begins with the server. Jinja2 provides the power to build dynamic, reusable HTML.
Pattern & Inheritance
- Base Layout: Use
base.htmlfor common headers, footers, and styles. - Block Inheritance: Use
{% block content %}to allow child templates to inject their specific content.
Reusability
- Macros: Like functions for HTML (e.g., a reusable button or form field).
- Includes: Component-level reusability for navigation bars or sidebars.
Logic & Context
- Control Flow:
{% if user.is_authenticated %},{% for item in items %}. - Filters: Formatting data directly in the template (e.g.,
{{ date|format_date }}).
Best Practices
- Never Render Raw HTML: Ensure variables are escaped to prevent XSS.
- Logic Placement: Keep complex calculations in Python, and only use templating for display logic.