Movies Database

For this example, we'll be modeling the following two entities connected by a many-to-many relationship:

Actor and Film entities connected by a many-to-many relationship.

We'll also use the following data:

Actors	Name	Date of Birth
	Natalie Portman	1981-06-09
	Orlando Bloom	1977-01-13
	Johnny Depp	1963-06-09
	Hugo Weaving	1960-04-04
	Christopher Lee	1922-05-27

Name	Year	Actors
Star Wars: Episode II - Attack of the Clones	2002	Natalie Portman, Christopher Lee
Pirates of the Caribbean: The Curse of the Black Python	2003	Orlando Bloom, Johnny Depp
The Lord of the Rings: The Return of the King	2003	Orlando Bloom, Hugo Weaving, Christopher Lee
V for Vendetta	2006	Natalie Portman, Hugo Weaving

In our current project, create a new application called movies. At the command line, type:
```
python manage.py startapp movies
```

Edit the sigcse/settings.py file so that we can connect to a sqlite3 database:

DATABASE_ENGINE = 'sqlite3'
DATABASE_NAME = '/home/aortiz/sigcse/movies/movies.db'
DATABASE_USER = ''
DATABASE_PASSWORD = ''
DATABASE_HOST = ''    
DATABASE_PORT = ''

Edit the sigcse/settings.py file so that we can use the Django administration site and our application's database:

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.admin',
    'sigcse.movies',
)

Edit the sigcse/urls.py. Uncomment the highlighted lines in order to define a URL for accessing the Django administration site:

from django.conf.urls.defaults import *

# Uncomment the next two lines to enable the admin:
from django.contrib import admin
admin.autodiscover()

urlpatterns = patterns('',
    # Example:
    # (r'^sigcse/', include('sigcse.foo.urls')),

    # Uncomment the admin/doc line below and add 'django.contrib.admindocs' 
    # to INSTALLED_APPS to enable admin documentation:
    # (r'^admin/doc/', include('django.contrib.admindocs.urls')),

    # Uncomment the next line to enable the admin:
    (r'^admin/(.*)', admin.site.root),
    (r'^hello/(\w+)/$', 'sigcse.hello.views.say'),
    (r'^fibonacci/(\d{1,4})/$', 'sigcse.fibonacci.views.do_it'),
)

Define the application models. Add the following code to the sigcse/movies/models.py file:

from django.db import models

class Actor(models.Model):
    name           = models.CharField(max_length=30)
    date_of_birth  = models.DateField()
    
    def __unicode__(self):
        return self.name

class Film(models.Model):
    name    = models.CharField(max_length=60)
    year    = models.IntegerField()
    actors  = models.ManyToManyField(Actor, related_name='films')
    
    def __unicode__(self):
        return self.name

Register the models that are to be managed using the administration site. Create a file named admin.py in the sigcse/movies folder with the following content:
```
from django.contrib import admin
from sigcse.movies import models 
 
admin.site.register(models.Actor)
admin.site.register(models.Film)
```
Synchronize the model definitions with the database. Type at the command line:
```
python manage.py syncdb
```
You'll be asked to create a superuser definition. Say yes, and type any additional requested information.

Add new information to the database using the Django shell. Type at the command line:

python manage.py shell

Type the following commands in the interactive shell in order to add two new instances of the Actor model:

>>> from sigcse.movies.models import Actor
>>> from datetime import date
>>> a1 = Actor(name='Natalie Portman', date_of_birth=date(1981, 6, 9))
>>> a1.save()
>>> a2 = Actor(name='Orlando Bloom', date_of_birth=date(1977, 1, 13))
>>> a2.save()

The following commands demonstrate how to retrieve the stored information:

>>> r = Actor.objects.all()
>>> r
[<Actor: Natalie Portman>, <Actor: Orlando Bloom>]
>>> a = r[0]
>>> a
<Actor: Natalie Portman>
>>> a.id
1
>>> a.name
u'Natalie Portman'
>>> a.date_of_birth
datetime.date(1981, 6, 9)
>>> a = Actor.objects.get(name='Orlando Bloom')
>>> a.id
2
>>> a.name
u'Orlando Bloom'
>>> a.date_of_birth
datetime.date(1977, 1, 13)

Open the administration site. Using your web browser, visit this following URL http://localhost:8000/admin/ and type all the remaining actor and film information found at the beginning of this page.

Once again, let's go to the interactive shell:

python manage.py shell

Let's now inspect programmatically the contents of the database:

>>> from sigcse.movies.models import Actor, Film
>>> r = Film.objects.filter(name__contains="clones")
>>> r
[<Film: Star Wars: Episode II - Attack of the Clones>]
>>> f = r[0]
>>> r = f.actors.all()
>>> r
[<Actor: Natalie Portman>, <Actor: Christopher Lee>]
>>> a = r[0]
>>> r = a.films.all()
>>> r
[<Film: Star Wars: Episode II - Attack of the Clones>, <Film: V for Vendetta>]

Exercises

Write a view/template in the current application that, given a certain year (as part of the URL), displays the name of all the films released that year (using an HTML unordered list). For example, given the URL http://localhost:8000/films/2003/ the output should be:
In the current application, write a view/template that displays in an HTML table all the actors stored in the database, sorted alphabetically by name. Include also her or his date of birth, as well as the names of all the films in which she or he has starred. For example, given the URL http://localhost:8000/actors/ the output should look something like this:

Web Development with Python and Django

Movies Database

Exercises