Book Image

Mastering Django: Core

By : Nigel George
Book Image

Mastering Django: Core

By: Nigel George

Overview of this book

Mastering Django: Core is a completely revised and updated version of the original Django Book, written by Adrian Holovaty and Jacob Kaplan-Moss - the creators of Django. The main goal of this book is to make you a Django expert. By reading this book, you’ll learn the skills needed to develop powerful websites quickly, with code that is clean and easy to maintain. This book is also a programmer’s manual that provides complete coverage of the current Long Term Support (LTS) version of Django. For developers creating applications for commercial and business critical deployments, Mastering Django: Core provides a complete, up-to-date resource for Django 1.8LTS with a stable code-base, security fixes and support out to 2018.
Table of Contents (33 chapters)
Mastering Django: Core
Credits
About the Author
www.PacktPub.com
Preface
Free Chapter
1
Introduction to Django and Getting Started

Date-Based Generic Views


Date-based generic views, provided in django.views.generic.dates, are views for displaying drilldown pages for date-based data.

ArchiveIndexView

A top-level index page showing the latest objects, by date. Objects with a date in the future are not included unless you set allow_future to True.

Context

In addition to the context provided by django.views.generic.list.MultipleObjectMixin (via django.views.generic.dates.BaseDateListView), the template's context will be:

  • date_list: A DateQuerySet object containing all years that have objects available according to queryset, represented as datetime.datetime objects, in descending order

Notes

  • Uses a default context_object_name of latest.
  • Uses a default template_name_suffix of _archive.
  • Defaults to providing date_list by year, but this can be altered to month or day using the attribute date_list_period. This also applies to all subclass views:
Example myapp/urls.py: 
from django.conf.urls import url 
from django.views.generic.dates import ArchiveIndexView 
 
from myapp.models import Article 
 
urlpatterns = [ 
    url(r'^archive/$', 
        ArchiveIndexView.as_view(model=Article, date_field="pub_date"), 
        name="article_archive"), 
] 

Example myapp/article_archive.html:

<ul> 
    {% for article in latest %} 
        <li>{{ article.pub_date }}: {{ article.title }}</li> 
    {% endfor %} 
</ul> 

This will output all articles.

YearArchiveView

A yearly archive page showing all available months in a given year. Objects with a date in the future are not displayed unless you set allow_future to True.

Context

In addition to the context provided by django.views.generic.list.MultipleObjectMixin (via django.views.generic.dates.BaseDateListView), the template's context will be:

  • date_list: A DateQuerySet object containing all months that have objects available according to queryset, represented as datetime.datetime objects, in ascending order
  • year: A date object representing the given year
  • next_year: A date object representing the first day of the next year, according to allow_empty and allow_future
  • previous_year: A date object representing the first day of the previous year, according to allow_empty and allow_future

Notes

  • Uses a default template_name_suffix of _archive_year

Example myapp/views.py:

from django.views.generic.dates import YearArchiveView 
 
from myapp.models import Article 
 
class ArticleYearArchiveView(YearArchiveView): 
    queryset = Article.objects.all() 
    date_field = "pub_date" 
    make_object_list = True 
    allow_future = True 

Example myapp/urls.py:

from django.conf.urls import url 
 
from myapp.views import ArticleYearArchiveView 
 
urlpatterns = [ 
    url(r'^(?P<year>[0-9]{4})/$', 
        ArticleYearArchiveView.as_view(), 
        name="article_year_archive"), 
] 

Example myapp/article_archive_year.html:

<ul> 
    {% for date in date_list %} 
        <li>{{ date|date }}</li> 
    {% endfor %} 
</ul> 
<div> 
    <h1>All Articles for {{ year|date:"Y" }}</h1> 
    {% for obj in object_list %} 
        <p> 
            {{ obj.title }}-{{ obj.pub_date|date:"F j, Y" }} 
        </p> 
    {% endfor %} 
</div> 

MonthArchiveView

A monthly archive page showing all objects in a given month. Objects with a date in the future are not displayed unless you set allow_future to True.

Context

In addition to the context provided by MultipleObjectMixin (via BaseDateListView), the template's context will be:

  • date_list: A DateQuerySet object containing all days that have objects available in the given month, according to queryset, represented as datetime.datetime objects, in ascending order
  • month: A date object representing the given month
  • next_month: A date object representing the first day of the next month, according to allow_empty and allow_future
  • previous_month: A date object representing the first day of the previous month, according to allow_empty and allow_future

Notes

  • Uses a default template_name_suffix of _archive_month

Example myapp/views.py:

from django.views.generic.dates import MonthArchiveView 
 
from myapp.models import Article 
 
class ArticleMonthArchiveView(MonthArchiveView): 
    queryset = Article.objects.all() 
    date_field = "pub_date" 
    make_object_list = True 
    allow_future = True 

Example myapp/urls.py:

from django.conf.urls import url 
 
from myapp.views import ArticleMonthArchiveView 
 
urlpatterns = [ 
    # Example: /2012/aug/ 
    url(r'^(?P<year>[0-9]{4})/(?P<month>[-\w]+)/$', 
        ArticleMonthArchiveView.as_view(), 
        name="archive_month"), 
    # Example: /2012/08/ 
    url(r'^(?P<year>[0-9]{4})/(?P<month>[0-9]+)/$', 
        ArticleMonthArchiveView.as_view(month_format='%m'), 
        name="archive_month_numeric"), 
] 

Example myapp/article_archive_month.html:

<ul> 
    {% for article in object_list %} 
        <li>{{ article.pub_date|date:"F j, Y" }}:  
            {{ article.title }} 
        </li> 
    {% endfor %} 
</ul> 
 
<p> 
    {% if previous_month %} 
        Previous Month: {{ previous_month|date:"F Y" }} 
    {% endif %} 
    {% if next_month %} 
        Next Month: {{ next_month|date:"F Y" }} 
    {% endif %} 
</p> 

WeekArchiveView

A weekly archive page showing all objects in a given week. Objects with a date in the future are not displayed unless you set allow_future to True.

Context

In addition to the context provided by MultipleObjectMixin (via BaseDateListView), the template's context will be:

  • week: A date object representing the first day of the given week
  • next_week: A date object representing the first day of the next week, according to allow_empty and allow_future
  • previous_week: A date object representing the first day of the previous week, according to allow_empty and allow_future

Notes

  • Uses a default template_name_suffix of _archive_week

Example myapp/views.py:

from django.views.generic.dates import WeekArchiveView 
 
from myapp.models import Article 
 
class ArticleWeekArchiveView(WeekArchiveView): 
    queryset = Article.objects.all() 
    date_field = "pub_date" 
    make_object_list = True 
    week_format = "%W" 
    allow_future = True 

Example myapp/urls.py:

from django.conf.urls import url 
 
from myapp.views import ArticleWeekArchiveView 
 
urlpatterns = [ 
    # Example: /2012/week/23/ 
    url(r'^(?P<year>[0-9]{4})/week/(?P<week>[0-9]+)/$', 
        ArticleWeekArchiveView.as_view(), 
        name="archive_week"), 
] 

Example myapp/article_archive_week.html:

<h1>Week {{ week|date:'W' }}</h1> 
 
<ul> 
    {% for article in object_list %} 
        <li>{{ article.pub_date|date:"F j, Y" }}: {{ article.title }}</li> 
    {% endfor %} 
</ul> 
 
<p> 
    {% if previous_week %} 
        Previous Week: {{ previous_week|date:"F Y" }} 
    {% endif %} 
    {% if previous_week and next_week %}--{% endif %} 
    {% if next_week %} 
        Next week: {{ next_week|date:"F Y" }} 
    {% endif %} 
</p> 

In this example, you are outputting the week number. The default week_format in the WeekArchiveView uses week format "%U" which is based on the United States week system where the week begins on a Sunday. The "%W" format uses the ISO week format and its week begins on a Monday. The "%W" format is the same in both the strftime() and the date.

However, the date template filter does not have an equivalent output format that supports the US based week system. The date filter "%U" outputs the number of seconds since the Unix epoch.

DayArchiveView

A day archive page showing all objects in a given day. Days in the future throw a 404 error, regardless of whether any objects exist for future days, unless you set allow_future to True.

Context

In addition to the context provided by MultipleObjectMixin (via BaseDateListView), the template's context will be:

  • day: A date object representing the given day
  • next_day: A date object representing the next day, according to allow_empty and allow_future
  • previous_day: A date object representing the previous day, according to allow_empty and allow_future
  • next_month: A date object representing the first day of the next month, according to allow_empty and allow_future
  • previous_month: A date object representing the first day of the previous month, according to allow_empty and allow_future

Notes

  • Uses a default template_name_suffix of _archive_day

Example myapp/views.py:

from django.views.generic.dates import DayArchiveView 
 
from myapp.models import Article 
 
class ArticleDayArchiveView(DayArchiveView): 
    queryset = Article.objects.all() 
    date_field = "pub_date" 
    make_object_list = True 
    allow_future = True 

Example myapp/urls.py:

from django.conf.urls import url 
 
from myapp.views import ArticleDayArchiveView 
 
urlpatterns = [ 
    # Example: /2012/nov/10/ 
    url(r'^(?P<year>[0-9]{4})/(?P<month>[-\w]+)/(?P<day>[0-9]+)/$', 
        ArticleDayArchiveView.as_view(), 
        name="archive_day"), 
] 

Example myapp/article_archive_day.html:

<h1>{{ day }}</h1> 
 
<ul> 
    {% for article in object_list %} 
        <li> 
        {{ article.pub_date|date:"F j, Y" }}: {{ article.title }} 
        </li> 
    {% endfor %} 
</ul> 
 
<p> 
    {% if previous_day %} 
        Previous Day: {{ previous_day }} 
    {% endif %} 
    {% if previous_day and next_day %}--{% endif %} 
    {% if next_day %} 
        Next Day: {{ next_day }} 
    {% endif %} 
</p> 

TodayArchiveView

A day archive page showing all objects for today. This is exactly the same as django.views.generic.dates.DayArchiveView, except today's date is used instead of the year/month/day arguments.

Notes

  • Uses a default template_name_suffix of _archive_today

Example myapp/views.py:

from django.views.generic.dates import TodayArchiveView 
 
from myapp.models import Article 
 
class ArticleTodayArchiveView(TodayArchiveView): 
    queryset = Article.objects.all() 
    date_field = "pub_date" 
    make_object_list = True 
    allow_future = True 

Example myapp/urls.py:

from django.conf.urls import url 
 
from myapp.views import ArticleTodayArchiveView 
 
urlpatterns = [ 
    url(r'^today/$', 
        ArticleTodayArchiveView.as_view(), 
        name="archive_today"), 
] 

Where is the example template for TodayArchiveView?

This view uses by default the same template as the DayArchiveView, which is in the previous example. If you need a different template, set the template_name attribute to be the name of the new template.

DateDetailView

A page representing an individual object. If the object has a date value in the future, the view will throw a 404 error by default, unless you set allow_future to True.

Context

  • Includes the single object associated with the model specified in the DateDetailView

Notes

  • Uses a default template_name_suffix of _detail
Example myapp/urls.py: 
from django.conf.urls import url 
from django.views.generic.dates import DateDetailView 
 
urlpatterns = [ 
    url(r'^(?P<year>[0-9]+)/(?P<month>[-\w]+)/(?P<day>[0-9]+)/ 
      (?P<pk>[0-9]+)/$', 
        DateDetailView.as_view(model=Article, date_field="pub_date"), 
        name="archive_date_detail"), 
] 

Example myapp/article_detail.html:

<h1>{{ object.title }}</h1>