Django学习笔记-02 搭建投票网站
1. 准备阶段
# 1. 创建投票应用
django-admin startproject mysite
cd mysite
python manage.py startapp polls
2. 配置Django
2.1 编辑mysite/setting.py配置应用；
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'polls.apps.PollsConfig',
]2.2 配置数据库
Python自带SQLite3数据库，Django默认使用SQLite3数据库，如果使用其它数据库请在mysite/settings.py文件中设置。
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}2.3 配置完成后创建数据
# 创建数据库
python manage.py makemigrations
# 同步数据
python manage.py migrate
# 创建超级管理员账号
python manage.py createsuperuser2.4 启动应用，访问后台
# python manage.py runserver 127.0.0.1:8000
python manage.py runserver通过浏览器访问：http://127.0.0.1:8000
3.设计数据库模型
- 编辑mysite/polls/model.py文件
from django.db import models
import datetime
from django.utils import timezone
# Create your models here.
class Question(models.Model):
question_text = models.CharField(max_length=256)
pub_date = models.DateTimeField('date published')
def __str__(self):
return self.question_text
def was_published_recently(self):
now = timezone.now()
return now - datetime.timedelta(days=1) <= self.pub_date <= now
was_published_recently.admin_order_field = 'pub_date'
was_published_recently.boolean = True
was_published_recently.short_description = 'Published recently?'
class Choice(models.Model):
question = models.ForeignKey(Question, on_delete=models.CASCADE)
choice_text = models.CharField(max_length=256)
votes = models.IntegerField(default=0)
def __str__(self):
return self.choice_text再次执行数据库同步
python manage.py makemigrations python manage.py migrate
4.后台管理
编辑mysite/polls/admin.py文件
from django.contrib import admin
from .models import Question, Choice
# Register your models here.
class ChoiceInline(admin.TabularInline):
model = Choice
extra = 3
class QuestionAdmin(admin.ModelAdmin):
search_fields = ['question_text']
list_filter = ['pub_date']
list_display = ('question_text', 'pub_date', 'was_published_recently')
fieldsets = [
(None, {'fields': ['question_text']}),
('Date information', {'fields': ['pub_date'], 'classes': ['collapse']}),
]
inlines = [ChoiceInline]
admin.site.register(Question, QuestionAdmin)启动应用，登陆后台管理界面，发布投票问题
5.编辑模板
在mysite/polls目录下创建templates/polls/目录
新建base.html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<meta name="description" content="">
<meta name="author" content="">
<!-- Block Title -->
<title>{% block title %}{% endblock %}</title>
<!-- Bootstrap core CSS -->
<link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
<!-- Custom styles for this template -->
<link href="starter-template.css" rel="stylesheet">
</head>
<body>
<nav class="navbar navbar-inverse navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar"
aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="/blog">Home</a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="/admin">Admin</a></li>
<li><a href="/about">About</a></li>
<li><a href="#contact">Contact</a></li>
</ul>
</div><!--/.nav-collapse -->
</div>
</nav>
<div class="container" style="margin-top: 50px;">
<div class="starter-template">
{% block content %}{% endblock %}
</div>
</div><!-- /.container -->
<script src="https://cdn.bootcss.com/jquery/1.12.4/jquery.min.js"></script>
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</body>
</html>在mysite/polls目录下新建static/polls/style.css文件
li a {
color: blue;
}
body {
background: white url("images/background.jpg") no-repeat;
}在mysite/polls目录下新建images文件夹，放置图片文件。
新建index.html
{% extends "polls\base.html" %}
{% block title %}Polls{% endblock %}
{% block content %}
{% load static %}
<link rel="stylesheet" type="text/css" href="{% static 'polls/style.css' %}" />
{% if latest_question_list %}
<ul>
{% for question in latest_question_list %}
<li><a href="{% url 'polls:detail' question.id %}">{{ question.question_text }}</a></li>
{% endfor %}
</ul>
{% else %}
<p>No polls are available.</p>
{% endif %}
{% endblock %}新建detail.html
{% extends "polls\base.html" %}
{% block title %}Polls{% endblock %}
{% block content %}
<h1>{{ question.question_text }}</h1>
{% if error_message %}<p><strong>{{ error_message }}</strong></p>{% endif %}
<form action="{% url 'polls:vote' question.id %}" method="post">
{% csrf_token %}
{% for choice in question.choice_set.all %}
<input type="radio" name="choice" id="choice{{ forloop.counter }}" value="{{ choice.id }}" />
<label for="choice{{ forloop.counter }}">{{ choice.choice_text }}</label><br/>
{% endfor %}
<input type="submit" value="Vote" />
</form>
{% endblock %}新建results.html
{% extends "polls\base.html" %}
{% block title %}Polls{% endblock %}
{% block content %}
<h1>{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
<li>{{ choice.choice_text }} -- {{ choice.votes }} vote{{ choice.votes | pluralize }}</li>
{% endfor %}
</ul>
<a href="{% url 'polls:detail' question.id %}">Vote again?</a>
{% endblock %}6. 编辑视图
编辑mysite/polls/view.py文件
from django.shortcuts import render, get_object_or_404
from django.http import HttpResponseRedirect
from django.urls import reverse
from django.views import generic
from .models import Question, Choice
from django.utils import timezone
# Create your views here.
class IndexView(generic.ListView):
template_name = 'polls/index.html'
context_object_name = 'latest_question_list'
def get_queryset(self):
return Question.objects.filter(
pub_date__lte=timezone.now()
).order_by('-pub_date')[:5]
class DetailView(generic.DetailView):
model = Question
template_name = 'polls/detail.html'
def get_queryset(self):
return Question.objects.filter(pub_date__lte=timezone.now())
class ResultsView(generic.DetailView):
model = Question
template_name = 'polls/results.html'
def vote(request, question_id):
question = get_object_or_404(Question, pk=question_id)
try:
selected_choice = question.choice_set.get(pk=request.POST['choice'])
except (KeyError, Choice.DoesNotExist):
return render(request, 'polls/detail.html',{
'question':question,
'error_message':"You didn't select a choice.",
})
else:
selected_choice.votes += 1
selected_choice.save()
return HttpResponseRedirect(reverse('polls:results', args=(question_id,)))7. 编辑URL
编辑mysite/urls.py文件
from django.contrib import admin
from django.urls import path, include
urlpatterns = [
path('admin/', admin.site.urls),
path('polls/', include('polls.urls')),
]新建mysite/polls/urls.py文件
from django.urls import path
from . import views
app_name = 'polls'
urlpatterns = [
path('', views.IndexView.as_view(), name='index'),
path('<int:pk>/', views.DetailView.as_view(), name='detail'),
path('<int:pk>/results/', views.ResultsView.as_view(), name='results'),
path('<int:question_id>/vote/', views.vote, name='vote'),
]再次启动服务，访问polls应用
8. 测试
编辑mysite/polls/test.py文件
from django.test import TestCase
# Create your tests here.
import datetime
from django.utils import timezone
from django.urls import reverse
from .models import Question
class QuestionModelTests(TestCase):
def test_was_published_recently_with_future_question(self):
time = timezone.now() + datetime.timedelta(days=30)
future_question = Question(pub_date=time)
self.assertIs(future_question.was_published_recently(), False)
def test_was_published_recently_with_old_question(self):
time = timezone.now() - datetime.timedelta(days=1, seconds=1)
old_question = Question(pub_date=time)
self.assertIs(old_question.was_published_recently(), False)
def test_was_published_recently_with_recent_question(self):
time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
recent_question = Question(pub_date=time)
self.assertIs(recent_question.was_published_recently(), True)
def create_question(question_text, days):
"""
Create a question with the given `question_text` and published the
given number of `days` offset to now (negative for questions published
in the past, positive for questions that have yet to be published).
"""
time = timezone.now() + datetime.timedelta(days=days)
return Question.objects.create(question_text=question_text, pub_date=time)
class QuestionIndexViewTests(TestCase):
def test_no_questions(self):
"""
If no questions exist, an appropriate message is displayed.
"""
response = self.client.get(reverse('polls:index'))
self.assertEqual(response.status_code, 200)
self.assertContains(response, "No polls are available.")
self.assertQuerysetEqual(response.context['latest_question_list'], [])
def test_past_question(self):
"""
Questions with a pub_date in the past are displayed on the
index page.
"""
create_question(question_text="Past question.", days=-30)
response = self.client.get(reverse('polls:index'))
self.assertQuerysetEqual(
response.context['latest_question_list'],
['<Question: Past question.>']
)
def test_future_question(self):
"""
Questions with a pub_date in the future aren't displayed on
the index page.
"""
create_question(question_text="Future question.", days=30)
response = self.client.get(reverse('polls:index'))
self.assertContains(response, "No polls are available.")
self.assertQuerysetEqual(response.context['latest_question_list'], [])
def test_future_question_and_past_question(self):
"""
Even if both past and future questions exist, only past questions
are displayed.
"""
create_question(question_text="Past question.", days=-30)
create_question(question_text="Future question.", days=30)
response = self.client.get(reverse('polls:index'))
self.assertQuerysetEqual(
response.context['latest_question_list'],
['<Question: Past question.>']
)
def test_two_past_questions(self):
"""
The questions index page may display multiple questions.
"""
create_question(question_text="Past question 1.", days=-30)
create_question(question_text="Past question 2.", days=-5)
response = self.client.get(reverse('polls:index'))
self.assertQuerysetEqual(
response.context['latest_question_list'],
['<Question: Past question 2.>', '<Question: Past question 1.>']
)
class QuestionDetailViewTests(TestCase):
def test_future_question(self):
"""
The detail view of a question with a pub_date in the future
returns a 404 not found.
"""
future_question = create_question(question_text='Future question.', days=5)
url = reverse('polls:detail', args=(future_question.id,))
response = self.client.get(url)
self.assertEqual(response.status_code, 404)
def test_past_question(self):
"""
The detail view of a question with a pub_date in the past
displays the question's text.
"""
past_question = create_question(question_text='Past Question.', days=-5)
url = reverse('polls:detail', args=(past_question.id,))
response = self.client.get(url)
self.assertContains(response, past_question.question_text)
执行测试
python manage.py test polls 参考链接