Django Product Evaluation

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This Evaluations is part of the Django Audit and focuses mainly on the Djangos Persistency Layer.

Important Note: This Evaluation contains simplifying constructs that are not part of the original Django Product. Thus you cannot use it a a django quick start.'

Installation

Basics

$ svn co http://code.djangoproject.com/svn/django/trunk/ django
$ cd django => /django
$ setupy.py develop
Install sqlite3 and python bindings for sqlite3

Schema Evolution Support - from Django Schema Evolution

within the directory /django
cd django => /django/django
$ svn co http://case.lazaridis.com/svn/main/django/rework rework
copy rework/django-admin.py to django/django/bin/

Further Resources (not needed)

Django Install Instructions (outdated comments)

Create a Project

$ django-admin.py startproject eval
$ cd eval

Create the Database

within folder "eval"

$ manage.py syncdb

Run the Development Server

$ manage.py runserver

Local Server

Create an Application

# within folder "eval"

$ manage.py startapp cars

# within /eval/settings.py

INSTALLED_APPS
...
'eval.cars'

Create a Class: Car

# within /cars/models.py

class Car(models.Model):

    manufacturer = models.CharField(maxlength=30)
    model = models.CharField(maxlength=30)
    modelYear = models.IntegerField()

    def __str__(self):
        return '%s %s %s' % (self.modelYear, self.manufacturer, self.model)

    class Admin:
        pass

Evolve the Database

$ manage.py syncdb

Add Instances

Use the Admin to add instances

Create a Class: Owner

class Owner(models.Model):

    name = models.CharField(maxlength=50)
    profession = models.CharField(maxlength=50)

    def __str__(self):
        return self.name

    class Admin:
        pass

Create a Relation: 1:1

class Car:
    ...
    owner = models.ForeignKey('Owner', blank=True, null=True)

Evolve the Database

$ manage.py syncdb

Add Instances and Relations

use the admin to create instances.

Create a Class: Driver

class Driver(models.Model):

    name = models.CharField(maxlength=50)
    licenseType = models.CharField(maxlength=30)
    car = models.ForeignKey(Car)

    def __str__(self):
       return self.name

    class Admin:
        pass

Create a Relation: 1:N

Within class *Driver*

    car = models.ForeignKey(Car)

Evolve the Database

$ manage.py syncdb

Add Instances and Relations

use the admin to create instances.

Define a Class: Road

class Road(models.Model):

    name = models.CharField(maxlength=50)
    length = models.IntegerField()

    def __str__(self):
        return self.name

    class Admin:
        pass

Create a Relation: M:N

class Road(models.Model):
    ...
    cars_passed = models.ManyToManyField('Car')

Evolve the Database

$ manage.py syncdb

Add Instances and Relations

use the admin to create instances.

Tasks / Suggestions for Django Team

Replace command "django-admin.py" by "django-admin" or "django"
Replace command "manage.py" by "django"
Enable sqlite3 database / filename by default
Externalize database settings (e.g. dbdefault.py)
Enable Admin application by default
Create a superuser by default (e.g. user:admin / pass:django)
Rename "startapp" to "createapp"
Provide basic Database Evolution (e.g. add field)
- Provided temporarily within Django Schema Evolution

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