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CherryPy / cherrypy / tutorial / tut06_default_method.py

Tutorial - The default method

Request handler objects can implement a method called "default" that
is called when no other suitable method/object could be found.
Essentially, if CherryPy2 can't find a matching request handler object
for the given request URI, it will use the default method of the object
located deepest on the URI path.

Using this mechanism you can easily simulate virtual URI structures
by parsing the extra URI string, which you can access through

The application in this tutorial simulates an URI structure looking
like /users/<username>. Since the <username> bit will not be found (as
there are no matching methods), it is handled by the default method.

import cherrypy

class UsersPage:
    def index(self):
        # Since this is just a stupid little example, we'll simply
        # display a list of links to random, made-up users. In a real
        # application, this could be generated from a database result set.
        return '''
            <a href="./remi">Remi Delon</a><br/>
            <a href="./hendrik">Hendrik Mans</a><br/>
            <a href="./lorenzo">Lorenzo Lamas</a><br/>
    index.exposed = True
    def default(self, user):
        # Here we react depending on the virtualPath -- the part of the
        # path that could not be mapped to an object method. In a real
        # application, we would probably do some database lookups here
        # instead of the silly if/elif/else construct.
        if user == 'remi':
            out = "Remi Delon, CherryPy lead developer"
        elif user == 'hendrik':
            out = "Hendrik Mans, CherryPy co-developer & crazy German"
        elif user == 'lorenzo':
            out = "Lorenzo Lamas, famous actor and singer!"
            out = "Unknown user. :-("
        return '%s (<a href="./">back</a>)' % out
    default.exposed = True

import os.path
tutconf = os.path.join(os.path.dirname(__file__), 'tutorial.conf')

if __name__ == '__main__':
    # CherryPy always starts with app.root when trying to map request URIs
    # to objects, so we need to mount a request handler root. A request
    # to '/' will be mapped to HelloWorld().index().
    cherrypy.quickstart(UsersPage(), config=tutconf)
    # This branch is for the test suite; you can ignore it.
    cherrypy.tree.mount(UsersPage(), config=tutconf)