1.14.4 Writing Applications

Below is a full example with a lot of functionality. It can be used as a base for your own applications.
import sys; sys.path.append('../')
from web.wsgi import *
import web.database.object, os

links = """<p><a href="example?mode=signOut">Sign out</a> | 
<a href="example?mode=view">View</a> | 
<a href="example?mode=add">Add</a></p>"""

def simpleApp(environ, start_response):

    person = web.database.object.Table("Person")
    person.add(column="String", name='firstName', required=True)
    person.addColumn(web.database.object.String(name="surname"))
    person.addColumn(
        web.database.object.StringSelect(
            name="profession", 
            options=[None, 'Developer', 'Web Developer'], 
            displayNoneAs='Not Specified'
        )
    )
    person.add(column="Bool", name='sex', displayTrueAs='Male', displayFalseAs='Female')
    database = web.database.object.Database()
    database.addTable(person)
    
    # Initialise the database
    database.init(environ['web.database.cursor'])

    if not database.tablesExist():
        database.createTables()

    mode = 'view'
    if environ['web.cgi'].has_key('mode'):
        mode = environ['web.cgi']['mode'].value

    # signIn mode needed to allow for sign in handling
    # you will be redirected to the correct place eventually
    if mode == 'signIn':
        start_response('403 User not signed in', [])
        environ['web.database.connection'].commit()
        return []
    elif mode == 'signOut':
        start_response('403 User not signed in', [])
        environ['web.database.connection'].commit()
        return []
    elif mode == 'add':
        if not environ.has_key('web.auth.user'): # No user signed in
            start_response('403 User not signed in', [])
            environ['web.database.connection'].commit()
            return []
        else:
            result = []
            form = database['Person'].form(stickyData={'mode':'add'}) 
            if len(environ['web.cgi']) > 1:             # Assume form submitted
                form.populate(environ['web.cgi'])
                if form.valid():      
                    entry = database['Person'].insert(all=form.dict())
                    result.append('''<html><h1>Entry Added</h1>%s
                        <p><a href="example">Go Back</a></html>'''%(form.frozen())
                    )
                else:
                    result.append( """<html>%s<h1>Error</h1><p>There were some invalid fields. 
                        Please correct them.</p>%s</html>"""%(links, form.html())
                    )
            else:
                result.append("""<html>%s<h1>Add Entry</h1>%s</html>"""%(links, form.html()))
            start_response('200 OK', [('Content-type','text/html')])
            environ['web.database.connection'].commit()
            return result
    else:
        entries = '<table border="1"><tr style="font-weight: bold;"><td>Firstname</td>'
        entries += '<td>Surname</td><td>Profession</td><td>Sex</td></tr>'
        for row in database['Person'].values():
            entries += '<tr><td>%s</td><td>%s</td><td>%s</td><td>%s</td></tr>'%(
                row['firstName'],
                row['surname'],
                row['profession'],
                row['sex']
            )
        entries += '</table>'
        info = """The table above shows people entries. To add an entry, click the add link above
        but you will need to sign in using the username <tt>john</tt> and the password <tt>bananas</tt>. 
        If you don't visit a page you will be signed out after 20 seconds and have to sign in again."""
        start_response('200 OK', [('Content-type','text/html')])
        environ['web.database.connection'].commit()
        return ["<html>%s<h1>Entries</h1><p>%s</p><p>%s</p></html>"%(links, entries,info)]

# Middleware Setup
application = error.Error(
    database.Database(
        session.Session(
            cgi.CGI(
                auth.Auth(
                    simpleApp, 
                    driver='database',
                    autoCreate=1,
                    expire=0,
                    idle=20,
                    template = """
                        <html>
                        <head><title>Sign In</title></head>
                        <body>
                        %s
                        <h1>Sign In</h1>
                        %%(form)s
                        <p>%%(message)s</p>
                        </body>
                        </html>
                    """%links,
                    redirectMethod='metaRefresh'
                ),
            ),
            expire = 1000,
            autoCreate = 1,
            driver='database',
        ),
        adapter = 'snakesql',
        database = 'wsgi-example',
        autoCreate = 1
    ),
)
You can test this example by running the WSGI server scripts/WSGIServer.py and visiting http://localhost:8000/example
Note: The authour of the web modules is currently building a framework called Bricks which will automate many of the tasks involved in manually writing an application such as the one above.