templates.md

Simplified EZT templating

asfquart has built-in decorators to apply an EZT template to a route/handler to generate an HTML response page from a "data dictionary".

EZT will take a template, and a data dictionary as inputs/value for that template, to produce an HTML page. The decorator specifies the template, and the function returns that data dictionary. These are combined and used as the page response for the route/endpoint.

import asfquart
APP = asfquart.APP

@APP.use_template('templates/example.ezt')
async def page_example():
    data = {
        'title': 'Example page',
        'count': 42,
        }
    return data

The APP.use_template() decorator takes an EZT Template instance, or a path to a source file. For the latter, it will install a "watcher" on that file. Should it change, the template will be automatically reloaded immediately. Its next rendering will use the changes, and no application restart is necessary.

The path form of use_template() takes a path relative to APP.app_dir or an absolute path.

Templates shared among routes

There are many times when a template might be shared across several routes. In such a scenario, the usage demonstrated above will load the template several times and the watcher will overwrite itself. Theoretically. This is as yet untested. And it should not be a problem. So they say.

The preferred approach is to load the template once, register it for watching, and then to provide the template to the use/render decorator. Example:

import asfquart
APP = asfquart.APP

T_EXAMPLE = APP.load_template('templates/example.ezt')

@APP.use_template(T_EXAMPLE)
async def page_example():
    data = {
        'title': 'Example page',
        'count': 42,
        }
    return data

@APP.use_template(T_EXAMPLE):
async def other_example():
    ...
    return other_data