Introduction

Django-Scaffolding creates pseudo-real-world placeholder data for your app. Data can be any type like names, cities, images and instances of your models. It's not a mocking framework, it creates real django model instances.

Usage

Add scaffolding to your INSTALLED_APPS

Create a scaffolds.py module within your app directory which contains the Scaffolding classes.

Sample models.py:

class Entry(models.Model):
    first_name = models.CharField('First Name', max_length=32)
    last_name = models.CharField('Last Name', max_length=32)
    comment = models.TextField('Comment', blank=True)
    image = models.ImageField(upload_to='uploads/%Y/%m/%d', blank=True, null=True)
    contest = models.ForeignKey(Contest)
    ...

Sample scaffolds.py:

import scaffolding
from scaffolding.library.flickr import FlickrInteresting

class EntryScaffold(object):
    first_name = scaffolding.FirstName(max_length=32)
    last_name = scaffolding.LastName(max_length=32)
    comment = scaffolding.OrBlank(scaffolding.LoremIpsum, paragraphs=1)
    contest = scaffolding.ForeignKey(queryset=Contest.objects.filter(name='testcontest'))
    image = scaffolding.RandomInternetImage(backend=FlickrInteresting)

    @classmethod
    finalize(cls, obj):
        # Just an example method
        obj.end_date = obj.start_date + datetime.timedelta(days=60)


scaffolding.register(Entry, EntryScaffold)

Mind the syntax for ForeignKey fields. You can assign an integer to the field but make sure the element with the corresponding key does exist. Of course you can also assign an object to the FK field.

To use the flickr library you need to have the Flickr API: http://stuvel.eu/flickrapi version 1.4.5 installed.

Run the management command to create the data:

manage.py scaffold myapp.MyModel 20

The number stands for the number of entries to be created.

Using scaffolding in the interpreter or in views

You can try out the included classes or your own modules in the shell. All classes are generators (called Tubes) that generate the values for the fields. start ./manage.py shell:

>>> from scaffolding import *
>>> r = RandInt(min=1, max=5)
>>> r.next()
[4]
>>> r.next()
[2]

>>> n = Name(gender='m')
>>> n.next()
[u'Ethan Schmid']
>>> n.next()
[u'Michael Schneider']

Using finalize()

If a Scaffold class contains a finalize(cls, obj) class method, the method is called after the model is created and before it is saved. This makes it possible to set properties which are dependent on field values.

Included Tubes

Name

Generates a random name. <gender> can be 'male', 'female', 'm' or 'f'.

FirstName and LastName

Generates only first or last name. Takes the gender attribute as well.

LoremIpsum

Generates a Lorem Ipsum Text. The number of paragraphs is defined in paragraphs.

RandInt

Generates a random integer between min and max.

ForeignKey

Takes a queryset and iterates through it. Assigns the item as ForeignKey to the field. Wraps around if there are not enough items.

ForeignKeyOrNone

The same for nullable ForeignKeys. split is the weight for positives. 0.2 yields 80% None.

RandomInternetImage

Creates a random image for an ImageField using an internet source. A Flickr 'Daily Interesting images' grabber is included.

RandomDate

Creates a random date between startdate and enddate. startdate and enddate have to be datetime.date instances.

RandomDatetime

Creates a random datetime instance between startdate and enddate. startdate and enddate have to be datetime.datetime instances. If a timezone is passed in the parameter timezone, the instance is timezone-aware.

UsCity

Returns a name of a US city and state. e.g. "New York, NY".

BookTitle

Creates a book title. This is a python implementation of the Random Title Generator.

URL

Creates a linkable to URL from a list of about 10000 URLs.

RandomEmail

Creates a random email. Parameters are length and domain.

AlwaysTrue

Returns True

AlwaysFalse

Returns False

TrueOrFalse

Randomly returns true or false. You can set a ratio for true or false by specifying true or false: e.g. false=3 returns 3 times as many False than Trues.

StaticValue

Takes one argument value and assigns it to the field.

RandomValue

Takes a list (not an iterable) as its lst argument and returns an element from it. You can use this for choice fields as well:

[c[0] for c in MyModel.MYCHOICES]

Every Value

Takes an iterable as its values argument and loops through them in order.

OrNone

This is a special tube that takes another tube as its first argument. It assigns a value from the passed class or None. This is useful for nullable fields. You can pass the arguments for the wrapped class as arguments to the OrNone class. There is one additional argument: split. This defines a ratio of useful to None. A ratio of 0.2 will give you 80% None.

OrBlank

The same as OrNone, but uses a blank string instead of None. Ideal for text fields that have blank=True.

Uuid

Generates a unique alphanumeric id. Takes an optional parameter format which can be one of uuid, hex or int. Default is hex. If the format is uuid it generates a Uuid4 instance.

Contrib

Crates a Custom Object. The backend class is the first parameter. The backend class has to inherit from Tube:

user = scaffolding.Contrib(FacebookTestUser, app_name='contest')

FacebookTestUser

Creates a Facebook User from the test users pool of the Facebook app. If there aren't enough test users new ones are automatically created. This requires the django-facebook-graph API. https://github.com/feinheit/django-facebook-graph

The module is in external.facebook_graph.