Overview

Django web components

Django-brick is a library that implements server-side web components for your Django application. The goal is to reuse code by building simple pluggable pieces. Think of Lego bricks for the web.

alt:https://upload.wikimedia.org/wikipedia/commons/thumb/3/32/Lego_Color_Bricks.jpg/1024px-Lego_Color_Bricks.jpg

Client-side programming has plenty responses for this task: React, Polymer, Vue.js, X-tag etc. Django Bricks provides a server-side alternative that can free you from writing some JavaScript and HTML ;).

Enter the brick

A brick is a Python component with a a well defined interface to present itself for the client. Usually this means that it can render itself as HTML5 (but sometimes we may need more complicated behaviors). Pehaps the most simple brick that you can use is just a HTML5 tag. Django-bricks implement these building blocks in the bricks.html5 module. The most important action a bricks.Tag brick can make is to render itself as HTML:

>>> from bricks.html5 import p
>>> elem = p("Hello World!", class_='hello')

This can be converted to HTML by calling str() on the element:

>>> print(str(elem))
<p class="hello">Hello World!</p>

Python and HTML have very different semantics. HTML’s syntax gravitates around tag attributes + children nodes and does not have a very natural counterpart in most programming languages. Of course we can build a tag in a imperative style, but the end result often feels awkward. We introduce a mini-language to declare HTML fragments in a more natural way:

>>> from bricks.html5 import div, p, h1
>>> fragment = \
...     div(class_="alert-box")[
...         h1('Hello Python'),
...         p('Now you can write HTML in Python!'),
...     ]

By default, bricks convert it to a very compact HTML; we insert no indentation and only a minimum whitespace. We can pretty print the fragment using the .pretty method:

>>> print(fragment.pretty())
<div class="alert-box">
  <h1>Hello Python</h1>
  <p>Now you can write HTML in Python!</p>
</div>

This is useful for debugging but, it is recommend to never output prettified HTML in production. This just stresses the rendering engine and produces larger files for no real gain for our end users and developers.