= Hello World =
An Albatross version of the ''classic'' (ahem) hello world application.
== Purpose ==
To demonstrate:
* a very basic application
* registration of page classes
* sending a HTML template file to the client
== Overview ==
The {{{HelloWorld}}} class simply initialises its base class, Albatross's prepackaged {{{SimpleApp}}}, and then registers the only page in the application, {{{StartPage}}}. The parameters passed to the {{{SimpleApp}}} constructor are:
* {{{base_url}}} - the path on the web server where the application is hosted. {{{base_url}}} is only used to generate links to other pages and so is largely irrelevant in this example.
* {{{template_path}}} - the directory containing the application's template files
* {{{start_page}}} - the page to display by default
* {{{secret}}} - an application-specific value used to ensure the integrity of session data that is sent to the browser
{{{StartPage}}} contains only one method, {{{page_display}}}, that tells Albatross to render the template file {{{startpage.html}}}.
Although it is not essential in this application (since there is only one page) it is customary for each page class to contain a class variable called {{{name}}} which uniquely identifes the page. The page's {{{name}}} is used in links.
== Source Code ==
=== helloworld.py ===
{{{
#!python
import albatross
from albatross import cgiapp
class HelloWorld(albatross.SimpleApp):
def __init__(self):
albatross.SimpleApp.__init__(
self,
base_url = '/',
template_path = '.',
start_page = StartPage.name,
secret = 'secret')
self.register_page(StartPage.name, StartPage())
class StartPage:
name = 'start'
def page_display(self, ctx):
ctx.run_template('startpage.html')
if __name__ == '__main__':
app = HelloWorld()
app.run(cgiapp.Request())
}}}
=== startpage.html ===
{{{
Hello World
Hello World.
}}}