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Version 116 (modified by Fran Boon, 14 years ago) ( diff )
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Developer Guide

Install a Development Environment

see InstallationGuidelinesDeveloper

Python

Indentation matters (use 4 spaces instead of Tabs)

lxml (XML I/O): http://codespeak.net/lxml/tutorial.html

More details at: DeveloperGuidelinesCodeConventions

Web2Py

This is an MVC environment (like Rails & Django. Django polls tutorial conversion course).

Web2Py can work at several different levels of abstraction.
The Sahana Eden framework (S3) is built on Web2Py's Auth/Crud classes in tools.py (with some remnants of the older T2), however sometimes we need more control therefore need to drop down a level or two.

http://web2py.com/examples/default/docs (recommend the 'New Cookbook' as well as the official book)

Recommend using the CLI to try out code snippets in the Web2Py environment (gluon, Model):

python web2py.py -S eden -M

Can execute a controller to be able to access its functions using:

execfile("applications/eden/controllers/mycontroller.py", globals())

Web2Py can be extended through Plugins & also has a recipes site.

Tutorial

This tutorial was given at SahanaCamp 1.1 in Taiwan:

http://www.slideshare.net/AidIQ/sahana-introduction-to-the-code-v2

Model

Defines databases in: /models/module.py

The Models are loaded 1st within Web2Py processing, before the controllers.
So you can import any global modules/set any global variables here.
The Models are imported in alphabetical order, so we load the files which other modules depend on 1st, hence naming them appropriately:
000_config.py, 01_crud.py, 02_pr.py, 03_gis.py, etc

Controller

Python functions in /controllers/module.py
e.g.

   def list_records():
       items = crud.select(table)
       return dict(items=items)

View

HTML/Javascript templates in /views/module/function.html

these are normal HTML/JS files with the ability to add in Python code (e.g. variables) surrounded by brackets: {{ interpreted python here }}
there should be an .html file available for each function in the module (name normally being the same as the function)
these normally inherit from views/layout.html which also includes the JavaScript from views/*_ajax.html
if there is no view defined then a default view will be displayed, which will show the values of all the data it can see, but not be formatted nicely

Static CSS/Javascript files are stored in /static