RoutesUrlMatching: tut11_routes.py

"""
Tutorial - Routes

In this tutorial, we will try to see what can be done with routes and what can't (at least with Routes 1.8).
We are going to create a very simple application customized for each user.
"""

import cherrypy

class Profile(object):

    def __init__(self):
        self. users = {
            'marc' : {'id': 1, 'email': 'marc@test.com', 'interests': ['knitting', 'coding', 'beer drinking']},
            'paul' : {'id': 2, 'email': 'paul@test.com', 'interests': ['kitty hunting', 'throwing rocks at children']}
        }

    def interests(self, user, id=None):
        user = user.lower()
        if user in self.users.keys():
            if id is not None and 0 <= int(id) < len(self.users[user]['interests']):
                return user + "'s interests: " + self.users[user]['interests'][int(id)]
            if id is None:
                return user + "'s interests: " + str(self.users[user]['interests'])
        return user + " does not exist. Or the id specified is not valid."
    
    def home(self, user, field=None):
        user = user.lower()
        if field not in ['email', 'interests']:
            field = None
        if user in self.users.keys():
            if field is not None and field in self.users[user].keys():
                return user + "'s " + field + ": " + str(self.users[user][field])
            else:
                res = ""
                for field in self.users[user].keys():
                    res += user+ "'s " + field + ": " + str(self.users[user][field]) + "<br/>"
                return res
        return user + " does not exist"



# getting the Routes dispatcher
d = cherrypy.dispatch.RoutesDispatcher()
root = Profile()

# here is the standard way of doing things with routes
# thanks to "URL Minimization", uri like
# /interests/marc
# /interests/marc/2
# are both matched by the same route.

#d.connect('second route', '/interests/:user/:id', controller=root, action='interests', id=0)
#d.connect('first route', '/home/:user/:field', controller=root, action='home', field=None)

# but what happens when you want to do prettier uri ?
# let's assume that your app is user centered.
# Having all url starting with the user name is by far nicer
# /marc/interests is more attractive than /interests/marc
# moreover, it would be very nice to be able to access "home" through /marc and not /marc/home
# the intuitive way of doing so is the following:
# d.connect('interests', '/:user/interests/:id', controller=root, action='interests', id=0)
# d.connect('home', '/:user/:field', controller=root, action='home', field=None)
# Note that the order is very important here, as Routes stops at the first route matched.
# but as you can see, accessing /marc does not display marc's home but the page you would expect to get at /marc/interests/0

# Although it should not be this way, the url minimization in routes makes this possible
# For further detail, look at Routes' doc. It has to do with minization and implicit values of variables
# The only solution is forget minimization and only use explicit routes.
# To do so, 2 things must be done:
# first of all, not doing things like 'field=None'
# second of all, disabling implicit routes
# the default form for a route is /:controller/:action/:id
# you can just do d.connect('/:controller/:action/:id') and Routes will interpret it as using the 'action' method on the specified controller with id as parameter (id = None if not specified)
# As you can see, there is some implicit minimization here
# However, this is not possible with Routes 1.8 (the one provided with a standard cherrypy3 installation)

# About classic minimization:
# If you want to be sure that no minimization is done, you must disable it (and of course use only explicit routes)
# You have to upgrade to at least Routes 1.9 to do this
# easy_install -U routes
# Moreover, with minimization disabled, you have to specify routes for each type of URL
# You can't do /:user/:field anymore with field default to None
# You have to specify /:user and /:user/:field
# This way everything is explicit and works fine

m = d.mapper
m.explicit = True # no implicit values for routes
m.minimization = False # no minimization (Routes > 1.9 only !)
d.connect('interests-1', '/:user/interests', controller=root, action='interests')
d.connect('interests-2', '/:user/interests/:id', controller=root, action='interests')
d.connect('home-1', '/:user', controller=root, action='home')
d.connect('home-2', '/:user/:field', controller=root, action='home', field=None)


# setting the dispatcher into the CherryPy config
conf = {'/' : {'request.dispatch' : d}}
# note that since the dispatcher handles the matching url/method
# we do not need to specify the root of the application anymore
cherrypy.tree.mount(root=None, config=conf)
cherrypy.server.quickstart()
cherrypy.engine.start()