Django

Projeto

"Projeto" é como Django chama a base do sistema, que não passa de um conjunto de apps.

Criado com django-admin startproject [PROJECTNAME] ..

Projeto: startproject

project/
├── manage.py
└── project
    ├── __init__.py
    ├── settings.py
    ├── urls.py
    └── wsgi.py
						

Time out: rodando o servidor de desenvolvimento

$ python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).

You have 13 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, contenttypes, sessions.
Run 'python manage.py migrate' to apply them.

October 24, 2016 - 23:04:50
Django version 1.10.2, using settings 'project.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
						

$ python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
  Applying admin.0001_initial... OK
  Applying admin.0002_logentry_remove_auto_add... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0002_alter_permission_name_max_length... OK
  Applying auth.0003_alter_user_email_max_length... OK
  Applying auth.0004_alter_user_username_opts... OK
  Applying auth.0005_alter_user_last_login_null... OK
  Applying auth.0006_require_contenttypes_0002... OK
  Applying auth.0007_alter_validators_add_error_messages... OK
  Applying auth.0008_alter_user_username_max_length... OK
  Applying sessions.0001_initial... OK
						

App

App é como o Django chama as pequenas partes que compõem o sistema.

Uma app pode ser entendida como uma tabela, ou um conjunto de tabelas que trabalham em conjunto ou conjunto de funções auxiliares.

App: startapp

django-admin startapp customers
                        

project/
├── customers
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   │   └── __init__.py
│   ├── models.py
│   ├── tests.py
│   └── views.py
├── db.sqlite3
├── manage.py
└── project
    ├── __init__.py
    ├── __init__.pyc
    ├── settings.py
    ├── settings.pyc
    ├── urls.py
    ├── urls.pyc
    └── wsgi.py
                        

App: models.py

from __future__ import unicode_literals

from django.db import models


class Customer(models.Model):

    name = models.CharField(max_length=100)

    def __str__(self):
        return self.name
                        

$ python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).
October 25, 2016 - 21:01:40
Django version 1.10.2, using settings 'project.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
                        

App: Adicionando ao projeto

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'customers'
]
                        

$ python manage.py makemigrations
Migrations for 'customers':
  customers/migrations/0001_initial.py:
    - Create model Customer
                        

$ python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, customers, sessions
Running migrations:
  Applying customers.0001_initial... OK
                        

App: Admin

from django.contrib import admin

from customers.models import Customer


class CustomerAdmin(admin.ModelAdmin):
    pass


admin.site.register(Customer, CustomerAdmin)
                        

Outro App

from __future__ import unicode_literals

from django.db import models

from customers.models import Customer


class Order(models.Model):

    customer = models.ForeignKey(Customer)
    date = models.DateField(auto_now_add=True)

    def __str__(self):
        return '{name} - {items} item'.format(
            name=self.customer.name,
            items=self.item_set.count())


class Item(models.Model):
    order = models.ForeignKey(Order)
    item = models.CharField(max_length=30)
    qtd = models.PositiveIntegerField()
    price = models.DecimalField(max_digits=8, decimal_places=2)

    @property
    def total(self):
        return self.qtd * self.price
                        

Admin

from django.contrib import admin

from orders.models import Order
from orders.models import Item


class Itemadmin(admin.TabularInline):
    model = Item


class OrderAdmin(admin.ModelAdmin):
    inlines = [Itemadmin]


admin.site.register(Order, OrderAdmin)