Writing your first Django app v. 1.8

manage.py

A command-line utility that lets you interact with this Django project in various ways

Object-Relational Mapper (ORM)

An abstraction layer for data in a database

mysite/__init__.py

An empty file that tells Python that this directory should be considered a Python package.

project

Another name for a collection of apps

models

Another name for database layout

self.assertEqual(response.status_code, 302)

Asser test for a HttpRedirect

self.assertContains(response, 'item 1')

Assert function that can check an entire response without needing to decode the html

assertTemplateUsed

Assert function to test templated used

assertContains()

Assert method used in testing to check whether something contains something

mysite/ manage.py mysite/ __init__.py settings.py urls.py wsgi.py

Basic directory layout of Django program mysite

LiveServerTestCase

Class to use for functional tests to build and tear down the database each test

{% csrf_token %}

Code for cross site request forgerie token

forloop.counter

Code snippet that tells django the iteration of a for loop

python manage.py runserver

Command that begans the python development server

django-admin startproject mysite

Command that creates project "mysite" in working directory

python manage.py migrate

Command that looks at the INSTALLED_APPS setting and creates any necessary database tables according to the database settings in your mysite/settings.py file and the database migrations shipped with the app

python manage.py migrate

Command that takes all the migrations that haven't been applied (Django tracks which ones are applied using a special table in your database called django_migrations) and runs them against your database - essentially, synchronizing the changes you made to your models with the schema in the database.

python manage.py createsuperuser

Command to create a superuser

python manage.py startapp polls

Command to create the app polls

class Choice(models.Model): question = models.ForeignKey(Question) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0)

Create a choice model that has a ForeignKey as Question, choice_text (char) and votes (Integer)

class Question(models.Model): question_text = models.CharField(max_length=200) pub_date = models.DateTimeField('date published')

Create a question model in django with a question_text variable set to a charField and a pub_date variable set to a DateTimeField

item_one = Item()

Create an Item object in django's test file

request.POST

Dictionary like object that lets you access submitted data by a key name

polls/ __init__.py admin.py migrations/ __init__.py models.py tests.py views.py

Directory layout of the app polls

mysite/mysite/

Directory that contains the python package for the program

{% for .. in .. %}

Django template syntax for iterating through a list

def __str__(self): / return self.choice_text

Function for each class in models that displays the human readable text of the class

render()

Function in views that takes a request object as its first argument, a template name as its second argument and a dictionary as its optional third argument. It returns an HttpResponse object of the given template rendered with the given context.

include()

Function that allows for referencing otherURLs conf. Django chops off whatever part of the URL matched up to that point and sends the remaining string to the included URLconf for further processing.

.decode()

Function that converts bytes into python strings

get_object_or_404()

Function that takes a Django model as its first argument and an arbitrary number of keyword arguments, which it passes to the get() function of the model's manager. It raises Http404 if the object doesn't exist.

HttpResponseRedirect()

Function where the argument takes a single argument: the URL to which the user will be redirected. You should always return an HttpResponseRedirect after successfully dealing with POST data. This tip isn't specific to Django; it's just good Web development practice.

unittest.TestCase

Functional test cases inherit from this class in Django

python -c "import django; print(django.get_version())"

Get django version from the interpreter

HttpRequest().method

HttpRequest method that returns the type of method being used (e.g. POST, GET)

from . import views

Import statement that is needed for urls.py to map the urls to the views

admin.site.register(class)

Line to insert into admin.py that registers the model with the admin site

python manage.py makemigrations polls

Method that tells Django that you've made some changes to your models (in this case, you've made new ones) and that you'd like the changes to be stored as a migration.

MVC

Model View Controller pattern

from django.conf.urls import url

Module that needs to be imported into urls.py

from django.http import HttpResponse

Module that needs to be imported to views.py

mysite/settings.py

Pathway of Settings/configuration for this Django project.

mysite/urls.py

Pathway of the URL declarations for this Django project; a "table of contents" of your Django-powered site

mysite/wsgi.py

Pathway of website gateway interface for the project

render_to_string( 'home.html', {'new_item_text': 'A new list item'}

Python function that render a HttpResponse to a string

Item.objects.all()

Retrieve all items from a table in django's testbench

item_one.text

Retrieve item_one's text attribute using django's test file

item_one.save()

Save item_one in djangos test file

.objects.create

Shorthand in views file to create a new object without having to call save()

{% load staticfiles %}

Tag to be included in html that loads static files

{% url %}

Template tag that can be used if you define the "name" paramater in the urls.py file

urls(regex, view, kwargs, name)

The arguments for the keyword function

django.db.models.Model

The django class on which models are built

INSTALLED_APPS

Tuple or dict in settings that holds the names of all Djanog applications that are activated in this Django instance

URLconfs

What django uses to map urls to their respective views

view

a "type" of Web page in your Django application that generally serves a specific function and has a specific template

app

another name for a web application that does something

integrated test

test type that relies on an external system (e.g. a database)