3.投票-1创建项目和子应用
创建项目
- 命令
$ python django-admin startproject mysite
- 目录结构
mysite/ # 项目容器、可任意命名 manage.py # 命令行工具 mysite/ # 纯 Python 包 # 你引用任何东西都要用到它 __init__.py # 空文件 告诉Python这个目录是Python包 settings.py # Django 项目配置文件 urls.py # URL 声明 # 就像网站目录 asgi.py # 部署时用的配置 # 运行在ASGI兼容的Web服务器上的 入口 wsgi.py # 部署时用的配置 # 运行在WSGI兼容的Web服务器上的
- 初始化数据库 迁移
$ python mangae.py makemigrations $ python manage.py migrate
Django 简易服务器
-
用于开发使用,Django 在网络框架方面很NB, 但在网络服务器方面不行~
专业的事让专业的程序做嘛,最后部署到 Nginx Apache 等专业网络服务器上就行啦。
-
自动重启服务器
对每次访问请求、重新载入一遍 Python 代码
新添加文件等一些操作 不会触发重启
-
命令
$ python manage.py runserver
E:PYTHON CODEmysite> E:PYTHON CODEmysite>python manage.py runserver Watching for file changes with StatReloader Performing system checks... System check identified no issues (0 silenced). June 29, 2022 - 22:35:10 Django version 4.0.5, using settings 'mysite.settings' Starting development server at http://127.0.0.1:8000/ Quit the server with CTRL-BREAK.
-
指定端口
$ python manage.py runserver 8080
创建应用
- 命令
$ python manage.py startapp polls
- 目录结构
polls/ __init__.py admin.py apps.py migrations/ __init__.py models.py tests.py views.py
编写应用视图
- 视图函数
# polls/views.py from django.shortcuts import render # Create your views here. from django.http import HttpRespose def index(rquest): return HttpResponse("投票应用 -首页")
配置路由
-
配置路由
# polls/urls.py 子应用路由 from django.urls import path from . import views urlpatterns = [ path('', views.index, name='index'), ]
# mysite/urls.py 全局路由 include()即插即用 from django.contrib import admin from django.urls import include, path urlpatterns = [ path('polls/', include('polls.urls')), path('admin/', admin.site.urls), ]
-
效果
path() 参数含义
path('', views.index, name='index'),
path('polls/', include('polls.urls'))
-
route 路径
一个匹配URL的规则,类似正则表达式。不匹配GET、POST传参 、域名
-
view 视图函数
Django 调用这个函数,默认传给函数一个 HttpRequest 参数
-
kwargs 视图函数参数
字典格式
-
name 给这条URL取一个温暖的名子~
可以在 Django 的任意地方唯一的引用。允许你只改一个文件就能全局地修改某个 URL 模式。
3.投票-2本地化和数据库API
本地化配置
-
时区和语言
# mysite/mysite/settings.py # Internationalization # https://docs.djangoproject.com/en/4.0/topics/i18n/ LANGUAGE_CODE = 'zh-hans' # 'en-us' TIME_ZONE = 'UTC' USE_I18N = True USE_TZ = True
-
为啥要在数据库之前?
配置时区,数据库可以以此做相应配置。比如时间的存放是以UTC还是本地时间...
数据库配置
- django 支持 sqlite mysql postgresql oracle
- 默认是sqlite 它是本地的一个文件name 哪里直接写了文件的绝对路径
# mysite/mysite/settings.py # Database # https://docs.djangoproject.com/en/4.0/ref/settings/#databases DATABASES = { 'default': { 'ENGINE': 'django.db.backends.sqlite3', 'NAME': BASE_DIR / 'db.sqlite3', } }
- 迁移 主要为Django默认的模型建表
python manage.py migrate
创建模型
-
编写
# mysite/polls/models.py from django.db import models class Question(models.Model): question_text = models.CharField(max_length=200) pub_date = models.DateTimeField('date published') class Choice(models.Model): question = models.ForeignKey(Question, on_delete=models.CASCADE) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0)
-
很多数据库的知识 都可以用到里面
Question Choice 类都是基于models.Model, 是它的子类。
类的属性--------表的字段
类名-----------表名
还有pub_date on_delete=models.CASCAD 级联删除, pub_date 的字段描述, vo tes的默认值, 都和数据库很像。
而且max_length这个个字段,让Django可以在前端自动校验我们的数据
激活模型
-
把配置注册到项目
# mysite/mysite/settings.py # Application definition INSTALLED_APPS = [ 'polls.apps.PollsConfig', 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', ]
-
做迁移-
仅仅把模型的配置信息转化成 Sql 语言
(venv) E:PYTHON CODEmysite>python manage.py makemigrations polls Migrations for 'polls': pollsmigrations 001_initial.py - Create model Question - Create model Choice
查看 Sql 语言 (对应我们配的 Sqlite 数据库的语法)
(venv) E:PYTHON CODEmysite>python manage.py sqlmigrate polls 0001
BEGIN;
--
-- Create model Question
--
CREATE TABLE "polls_question" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "question_text" varchar(200) NOT NULL, "pub_data" datetime NOT NULL
);
--
-- Create model Choice
--
CREATE TABLE "polls_choice" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL, "quest
ion_id" bigint NOT NULL REFERENCES "polls_question" ("id") DEFERRABLE INITIALLY DEFERRED);
CREATE INDEX "polls_choice_question_id_c5b4b260" ON "polls_choice" ("question_id");
COMMIT;
- 执行迁移
(venv) E:PYTHON CODEmysite>python manage.py migrate Operations to perform: Apply all migrations: admin, auth, contenttypes, polls, sessions Running migrations: Applying polls.0001_initial... OK (venv) E:PYTHON CODEmysite>
API 的初体验
- 进入shell
python manage.py shell
- 增
- (venv) E:PYTHON CODEmysite>python manage.py shell Python 3.9.1 (tags/v3.9.1:1e5d33e, Dec 7 2020, 17:08:21) [MSC v.1927 64 bit (AMD64)] on win32 Type "help", "copyright", "credits" or "license" for more information. (InteractiveConsole) >>> >>> from polls.models import Question, Choice >>> from django.utils import timezone >>> >>> q = Question( question_text = "what's up ?", pub_date=timezone.now() ) >>> >>> q.save() >>>
- 查看字段
>>> q.id 1 >>> q.question_text "what's up ?" >>> >>> q.pub_date datetime.datetime(2022, 7, 6, 5, 46, 10, 997140, tzinfo=datetime.timezone.utc) >>>
- 改
>>> q.question_text = 'are you kidding me ?' >>> q.save() >>> >>> q.question_text 'are you kidding me ?' >>> >>> >>> >>> Question.objects.all() <QuerySet [<Question: Question object (1)>]> >>> >>>
下面写点更人性化的方法
-
__str__
方法默认打印自己的text字段,便于查看
后台展示对象数据也会用这个字段
class Question(models.Model): ... def __str__(self): return self.question_text class Choice(models.Model): ... def __str__(self): return self.choice_text
- 自定义方法
class Question(models.Model): ... def was_published_recently(self): return self.pub_date >= timezone.now()-datetime.timedelta(days=1)
-
__str__
方法效果(venv) E:PYTHON CODEmysite>python manage.py shell Python 3.9.1 (tags/v3.9.1:1e5d33e, Dec 7 2020, 17:08:21) [MSC v.1927 64 bit (AMD64)] on win32 Type "help", "copyright", "credits" or "license" for more information. (InteractiveConsole) >>> >>> from polls.models import Question, Choice >>> >>> Question.objects.all() <QuerySet [<Question: are you kidding me ?>]> >>> >>> Question.objects.filter(id=1) <QuerySet [<Question: are you kidding me ?>]> >>>
-
按属性查
>>> >>> Question.objects.filter(question_text__startswith='are') <QuerySet [<Question: are you kidding me ?>]> >>> >>> from django.utils import timezone >>> >>> current_year = timezone.now().year >>> Question.objects.get(pub_date__year=current_year) <Question: are you kidding me ?> >>> >>> Question.objects.get(id=2) Traceback (most recent call last): File "<console>", line 1, in <module> File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsmanager.py", line 85, in manager_method return getattr(self.get_queryset(), name)(*args, **kwargs) File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsquery.py", line 496, in get raise self.model.DoesNotExist( polls.models.Question.DoesNotExist: Question matching query does not exist. >>> >>>
-
更多操作
用pk找更保险一些,有的model 不以id 为主键
>>> Question.objects.get(pk=1) <Question: are you kidding me ?> >>> # 自定义查找条件 >>> q = Question.objects.get(pk=1) >>> q.was_published_recently() True >>> # 安主键获取对象 >>> q = Question.objects.get(pk=1) >>> q.choice_set.all() <QuerySet []> >>> # 增 问题对象关系到选项对象 >>> q.choice_set.create(choice_text='Not much', votes=0) <Choice: Not much> >>> >>> q.choice_set.create(choice_text='The sky', votes=0) <Choice: The sky> >>> >>> q.choice_st.create(choice_text='Just hacking agin', votes=0) Traceback (most recent call last): File "<console>", line 1, in <module> AttributeError: 'Question' object has no attribute 'choice_st' >>> >>> q.choice_set.create(choice_text='Just hacking agin', votes=0) <Choice: Just hacking agin> >>> >>> >>> c = q.choice_set.create(choic_text='Oh my god.', votes=0) Traceback (most recent call last): File "<console>", line 1, in <module> File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsfieldsrelated_descriptors.py", line 747, in create return super(RelatedManager, self.db_manager(db)).create(**kwargs) File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsmanager.py", line 85, in manager_method return getattr(self.get_queryset(), name)(*args, **kwargs) File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsquery.py", line 512, in create obj = self.model(**kwargs) File "E:PYTHON CODEStudyBuddyvenvlibsite-packagesdjangodbmodelsbase.py", line 559, in __init__ raise TypeError( TypeError: Choice() got an unexpected keyword argument 'choic_text' >>> # 选项 关系 到问题 >>> c = q.choice_set.create(choice_text='Oh my god.', votes=0) >>> >>> c.question <Question: are you kidding me ?> >>> >>> q.choice_set.all() <QuerySet [<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking agin>, <Choice: Oh my god.>]> >>> >>> >>> q.choice_set.count() 4 >>> >>> Choice.objects.filter(question__pub_date__year=current_year) <QuerySet [<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking agin>, <Choice: Oh my god.>]> >>> >>>
-
删
>>> c = q.choice_set.filter(choice_text__startswith='Just hacking') >>> c.delete() (1, {'polls.Choice': 1}) >>> >>> q.choice_set.all() <QuerySet [<Choice: Not much>, <Choice: The sky>, <Choice: Oh my god.>]> >>> >>>
管理页面
- 创建用户
(venv) E:PYTHON CODEmysite>python manage.py createsuperuser 用户名: admin 电子邮件地址: admin@qq.com Password: Password (again): 密码长度太短。密码必须包含至少 8 个字符。 这个密码太常见了。 Bypass password validation and create user anyway? [y/N]: y Superuser created successfully.
- 启动 开发服务器
python manage.py runserver
- login
http://localhost:8000/admin/
- 让我们的polls 投票应用也展示在后台
# mysite/polls/admin.py from .models import Question, Choice admin.site.register(Question) admin.site.register(Choice)
3.投票-3模板和路由
编写更多视图
# polls/views.py
...
def detail(request, question_id):
return HttpResponse(f"当前问题id:{question_id}")
def results(request, question_id):
return HttpResponse(f"问题id:{question_id}的投票结果")
def vote(request, question_id):
return HttpResponse(f"给问题id:{question_id}投票")
添加url
- 全局我们已经加过
urlpatterns = [ path('admin/', admin.site.urls), path('polls/', include('polls.urls')), ]
- 应用程序添加如下
# polls/urls.py from django.urls import path from . import views urlpatterns = [ path('', views.index, name='index'), path('<int:question_id>/', views.detail, name='detail'), path('<int:question_id>/results/', views.results, name='results'), path('<int:question_id>/vote/', views.vote, name='vote'), ]
看看效果
-
path 里的参数很敏感 结尾含/ 的访问时也必须含 / 否则404
-
以 /polls/1/ 为例分析匹配过程
- 从mysite/settings.py 载入
ROOT_URLCONF = 'mysite.urls'
- 从urls.py 的“polls/”匹配到 polls/ 载入
polls.urls
- 从polls/urls.py 的“int:question_id/”匹配到 1/ ,获取int型的 1 转发给视图函数 views.details
- 从mysite/settings.py 载入
升级index 视图 展示近期5个投票问题
-
编写视图
def index(request): latest_question_list = Question.objects.order_by('-pub_date')[:5] output = ','.join([q.question_text for q in latest_question_list]) return HttpResponse(output)
-
好吧,总共就一个
-
加点
这里直接把页面内容,写到了视图函数里,写死的。很不方便,下面用模板文件来处理这个问题
模板文件
- 创建polls存放 模板文件的 文件夹 为什么里面多套了一层polls?没看出他有区分的作用,第一个polls不已经区分过了?
polls/templates/polls/
- 主要内容
# polls/templates/polls/index.html {% if latest_question_list %} <ul> {% for question in latest_question_list %} <li> <a href="/polls/{{ question.id }}/">{{question.question_text}}</a> </li> {% endfor %} </ul> {% else %} <p>暂时没有开放的投票。</p> {% endif %}
-
修改视图函数
这里函数载入index.html模本,还传给他一个上下文字典context,字典把模板里的变量映射成了Python 对象
# polls/views.py ... from django.template import loader def index(request): latest_question_list = Question.objects.order_by('-pub_date')[:5] template = loader.get_template('polls/index.html') context = { 'latest_question_list': latest_question_list, } return HttpResponse(template.render(context, request)) ...
-
效果
-
快捷函数 render()
上面的视图函数用法很普遍,有种更简便的函数替代这一过程
# polls/views.py ... from django.template import loader import django.shortcuts import render def index(request): latest_question_list = Question.objects.order_by('-pub_date')[:5] #template = loader.get_template('polls/index.html') context = { 'latest_question_list': latest_question_list, } #return HttpResponse(template.render(context, request)) return render(request, 'polls/index.html', context) ...
优雅的抛出 404
-
修改 detail 视图函数
# polls/views.py ... def detail(request, question_id): try: question = Question.objects.get(pk=question_id) except: raise Http404("问题不存在 !") # return HttpResponse(f"当前问题id:{question_id}") return render(request, 'polls/detail.html', {'question': question})
-
编写模板
# polls/templates/polls/detail.html {{ question }}
-
效果
-
快捷函数 get_object_or_404()
# polls/views.py from django.shortcuts import render, get_object_or_404 ... def detail(request, question_id): question = get_object_or_404(Question, pk=question_id) return render(request, 'polls/detail.html', {'question': question})
- 效果
使用模板系统
- 对detail.html获取的question变量进行分解 展示
-
模板系统用
.
来访问变量属性 -
如
question.question_text
先对question用字典查找nobj.get(str)------>属性查找obj.str---------->列表查找obj[int]当然在第二步就成功的获取了question_text属性,不在继续进行。 -
其中
question.choice_set.all
解释为Python代码question.choice_set.all()
# polls/templates/polls/detail.html<h1>{{ question.question_text }}</h1><ul> {% for choice in question.choice_set.all %} <li>{{ choice.choice_text }}</li> {% endfor %}</ul>
-
- 效果
去除 index.html里的硬编码
- 其中的'detail' 使我们在urls.py 定义的名称
# polls/urls.py path('<int:question_id>/', views.detail, name='detail'),
# polls/templates/polls/index.html <!--<li>--> <!-- <a href="/polls/{{ question.id }}/">{{question.question_text}}</a>--> <!--</li>--> <li> <a href="{% url 'detail' question.id %}">{{question.question_text}}</a> </li>
- 有啥用?
-
简单明了 书写方便
-
我们修改.html 的真实位置后, 只需在urls.py 同步修改一条记录, 就会在所有模板文件的无数个连接中生效
大大的节省时间
-
为URL添加命名空间
-
为什么?
上面去除硬链接方便了我们。我们只有1个应用polls有自己的detail.html模板,但有多个应用同时有名字为detail.html的模板时呢?
Django看到{% url %} 咋知道是哪个应用呢?
-
怎么加 ?
# polls/urls.py app_name = 'polls' ...
-
修改.html模板文件
# polls/templates/polls/index.html <!--<li>--> <!-- <a href="/polls/{{ question.id }}/">{{question.question_text}}</a>--> <!--</li>--> <!--<li>--> <!-- <a href="{% url 'detail' question.id %}">{{question.question_text}}</a>--> <!--</li>--> <li> <a href="{% url 'polls:detail' question.id %}">{{question.question_text}}</a> </li>
3.投票-4投票结果保存 和 Django通用模板
投票结果保存
前端
# polls/templates/polls/detail.html
{#<h1>{{ question.question_text }}</h1>#}
{#<ul>#}
{# {% for choice in question.choice_set.all %}#}
{# <li>{{ choice.choice_text }}</li>#}
{# {% endfor %}#}
{#</ul>#}
<form action="{% url 'polls:vote' question.id %}" method="post">
{% csrf_token %}
<fieldset>
...
</fieldset>
<input type="submit" value="投票">
</form>
# polls/templates/polls/detail.html
<form action="{% url 'polls:vote' question.id %}" method="post">
{% csrf_token %}
<fieldset>
<legend><h1>{{ question.question_text }}</h1></legend>
{% if error_message %}
<strong><p>{{ error_message }}</p></strong>
{% endif %}
{% 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>
{% endfor %}
</fieldset>
<input type="submit" value="投票">
</form>
路由
# polls/urls.py
path('<int:question_id>/vote/', views.vote, name='vote'),
视图
vote
# polls/views.py¶
# ...
from django.http import HttpResponseRedirect
from django.urls import reverse
# ...
# def vote(request, question_id):
# return HttpResponse(f"给问题id:{question_id}投票")
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': "选择为空, 无法提交 !"
})
else:
selected_choice.votes += 1
selected_choice.save()
# 重定向到其他页面 防止误触重复投票
return HttpResponse(reverse('polls:results', args=(question.id, )))
result
# polls/views.py¶
from django.shortcuts import get_object_or_404, render
def results(request, question_id):
question = get_object_or_404(Question, pk=question_id)
return render(request, 'polls/results.html', {'question': question})
前端
新建文件
# polls/templates/polls/results.html¶
<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 %}">继续投票</a>
降低冗余 URLConf
修改url
# mysite/polls/urls.py
from django.urls import path
from . import views
app_name = 'polls'
# urlpatterns = [
#
# path('', views.index, name='index'),
#
# path('<int:question_id>/', views.detail, name='detail'),
#
# path('<int:question_id>/results/', views.results, name='results'),
#
# path('<int:question_id>/vote/', views.vote, name='vote'),
#
#
# ]
urlpatterns = [
path('', views.IndexView.as_view(), name='index'),
path('<int:pk>/', views.DeatilView.as_view(), name='detail'),
path('<int:pl>/results/', views.ResultsViews.as_view(), name='results'),
path('<int:question_id>/vote/', views.vote, name='vote')
]
修改视图
ListView 和 DetailView 。这两个视图分别抽象“显示一个对象列表”和“显示一个特定类型对象的详细信息页面”这两种概念。
每个通用视图需要知道它将作用于哪个模型。 这由 model 属性提供。
template_name 属性是用来告诉 Django 使用一个指定的模板名字,而不是自动生成的默认名字。
自动生成的 context 变量是 question_list。为了覆盖这个行为,我们提供 context_object_name 属性,表示我们想使用 latest_question_list。作为一种替换方案,
# polls/views.py
from django.urls import reverse
# ...
# def index(request):
# latest_question_list = Question.objects.order_by('-pub_date')[:5]
#
# template = loader.get_template('polls/index.html')
# context = {
# 'latest_question_list': latest_question_list,
# }
#
# return HttpResponse(template.render(context, request))
# 用Django 通用视图 重写index, detail, results视图
class IndexView(generic.ListView):
template_name = 'polls/index.html'
context_object_name = 'latest_question_list'
def get_queryset(self):
"""返回最近的 5 个投票问题"""
return Question.objects.order_by('-pub_date')[:5]
class DetailView(generic.DetailView):
model = Question
template_name = 'polls/detail.html'
class ResultsView(generic.DetailView):
model = Question
template_name = 'polls/detail.html'
# def detail(request, question_id):
# # try:
# # question = Question.objects.get(pk=question_id)
# #
# # except:
# # raise Http404("问题不存在 !")
#
# # return HttpResponse(f"当前问题id:{question_id}")
#
# question = get_object_or_404(Question, pk=question_id)
# return render(request, 'polls/detail.html', {'question': question})
#
#
# # def results(request, question_id):
# # return HttpResponse(f"问题id:{question_id}的投票结果")
#
# def results(request, question_id):
# question = get_object_or_404(Question, pk=question_id)
# return render(request, 'polls/results.html', {'question': question})
# def vote(request, question_id):
# return HttpResponse(f"给问题id:{question_id}投票")
3.投票-5自动化测试 模型
自动化测试
一个bug
当设定发布时间为很远的未来的时间时,函数.was_published_recently()竟然返回True
$ python manage.py shell
>>> import datetime
>>> from django.utils import timezone
>>> from polls.models import Question
>>> # create a Question instance with pub_date 30 days in the future
>>> future_question = Question(pub_date=timezone.now() + datetime.timedelta(days=30))
>>> # was it published recently?
>>> future_question.was_published_recently()
True
编写测试用例
针对上面的bug写个脚本,用来测试这个bug
# polls/tests.py
import datetime
from django.test import TestCase
from django.utils import timezone
from .models import Question
class QuestionModelTests(TestCase):
def test_was_published_recently_with_future_question(self):
"""
was_published_recently() returns False for questions whose pub_date
is in the future.
"""
time = timezone.now() + datetime.timedelta(days=30)
future_question = Question(pub_date=time)
self.assertIs(future_question.was_published_recently(), False)
我们创建了一个 django.test.TestCase 的子类,并添加了一个方法,此方法创建一个 pub_date 时未来某天的 Question 实例。然后检查它的 was_published_recently() 方法的返回值——它 应该 是 False。
运行
# python manage.py test polls
(venv) E:PYTHON CODEmysite>
(venv) E:PYTHON CODEmysite>python manage.py test polls
Found 1 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
E
======================================================================
ERROR: test_was_published_recently_with_future_questsion (polls.tests.QuestionModelTests)
当日期为 未来 时间时 was_published_recently() 应该返回 False
----------------------------------------------------------------------
Traceback (most recent call last):
File "E:PYTHON CODEmysitepollstests.py", line 16, in test_was_published_recently_with_future_questsion
time = timezone.now() + datetime.timedelta(day=30)
TypeError: 'day' is an invalid keyword argument for __new__()
----------------------------------------------------------------------
Ran 1 test in 0.001s
FAILED (errors=1)
Destroying test database for alias 'default'...
(venv) E:PYTHON CODEmysite>
修复Bug
限制下界为当前
# mysite/polls/models.py
#...
class Question(models.Model):
question_text = models.CharField(max_length=200)
pub_date = models.DateTimeField('date published')
def __str__(self):
return self.question_text
# def was_published_recently(self):
#
# return self.pub_date >= timezone.now()-datetime.timedelta(days=1)
def was_published_recently(self):
now = timezone.now()
# 发布时间比现在小 比一天之前大 (即最近一天发布)
return now - datetime.timedelta(days=1) <= self.pub_date <= now
#...
测试其他时间段情况
class QuestionModelTests(TestCase):
def test_was_published_recently_with_future_question(self):
"""
当日期为 未来 时间时 was_published_recently() 应该返回 False
"""
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_recent_question(self):
"""
当日期为 最近 时间时 was_published_recently() 应该返回 False
"""
time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
future_question = Question(pub_date=time)
self.assertIs(future_question.was_published_recently(), True)
def test_was_published_recently_with_old_question(self):
"""
当日期为 过去(至少一天前) 时间时 was_published_recently() 应该返回 False
"""
time = timezone.now() + datetime.timedelta(days=1, seconds=1)
future_question = Question(pub_date=time)
self.assertIs(future_question.was_published_recently(), False)
运行
Microsoft Windows [版本 10.0.22000.978]
(c) Microsoft Corporation。保留所有权利。
(venv) E:PYTHON CODEmysite>python manage.py polls test
Unknown command: 'polls'
Type 'manage.py help' for usage.
(venv) E:PYTHON CODEmysite>python manage.py test polls
Found 3 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
...
----------------------------------------------------------------------
Ran 3 tests in 0.002s
OK
Destroying test database for alias 'default'...
(venv) E:PYTHON CODEmysite>
3.投票-6自动化测试 视图
Client 一个工具
这个很像我之前学过的,requests
但他更细节更贴合Django的视图,它可以直接捕获视图函数传过来的参数
Microsoft Windows [版本 10.0.22000.978]
(c) Microsoft Corporation。保留所有权利。
(venv) E:PYTHON CODEmysite>python manage.py shell
Python 3.9.1 (tags/v3.9.1:1e5d33e, Dec 7 2020, 17:08:21) [MSC v.1927 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>
>>>
>>> from django.test.utils import setup_test_environment
>>>
>>> setup_test_environment()
>>>
>>>
>>> from django.test import Client
>>>
>>> client = Client()
>>>
>>> r = client.get('/')
Not Found: /
>>>
>>> r.status_code
404
>>>
>>> from django.urls import reverse
>>>
>>> r = client.get(reverse("polls:index"))
>>>
>>> r .status_code
200
>>>
>>>
>>>
>>>
>>>
>>> r.content
b'n <ul>n n <li>n <a href="/polls/5/">Django is nice?</a>n </li>n n <li>n <a href="/polls/4/">I love Lisa.</a>n </li>n
n <li>n <a href="/polls/3/">do you lik ch best?</a>n </li>n n <li>n <a href="/polls/2/">are you okay?</a>n </li>n n <li
>n <a href="/polls/1/">are you kidding me ?</a>n </li>n n </ul>nn'
>>>
>>>
>>>
>>>
>>>
>>> r.context['latest_question_list']
<QuerySet [<Question: Django is nice?>, <Question: I love Lisa.>, <Question: do you lik ch best?>, <Question: are you okay?>, <Question: are you kidding me ?>]>
>>>
>>>
一个 Bug
按照逻辑,当投票发布时间是未来时,视图应当忽略这些投票
修复 Bug
# polls/views.py
class IndexView(generic.ListView):
template_name = 'polls/index.html'
context_object_name = 'latest_question_list'
def get_queryset(self):
"""返回最近的 5 个投票问题"""
#return Question.objects.order_by('-pub_date')[:5]
return Question.objects.filter(pub_date__lte=timezone.now()).order_by('-pub_date')[:5]
测试用例
写个投票脚本,用于产生数据
# polls/test.py
def create_question(question_text, days):
"""
一个公用的快捷函数用于创建投票问题
"""
time = timezone.now() + datetime.timedelta(days=days)
return Question.objects.create(question_text=question_text, pub_date=time)
测试类
class QuestionIndexViewTests(TestCase):
def test_no_questions(self):
"""
不存在 questions 时候 显示
"""
res = self.client.get(reverse('polls:index'))
self.assertEqual(res.status_code, 200)
#self.assertContains(res, "没有【正在进行】的投票。") # 是否显示“没有【正在进行】的投票。”字样
self.assertQuerysetEqual(res.context['latest_question_list'], [])
def test_past_question(self):
"""
发布时间是 past 的 question 显示到首页
"""
question = create_question(question_text="Past question.", days=-30)
res = self.client.get(reverse("polls:index"))
self.assertQuerysetEqual(
res.context['latest_question_list'],
[question],
)
def test_future_question(self):
"""
发布时间是 future 不显示
"""
create_question(question_text="未来问题!", days=30)
res = self.client.get(reverse('polls:index'))
#self.assertContains(res, "没有【可用】的投票")
self.assertQuerysetEqual(res.context['latest_question_list'], [])
def test_future_question_and_past_question(self):
"""
存在 past 和 future 的 questions 仅仅显示 past
"""
question = create_question(question_text="【过去】问题!", days=-30)
create_question(question_text="【未来】问题!", days=30)
response = self.client.get(reverse('polls:index'))
self.assertQuerysetEqual(
response.context['latest_question_list'],
[question],
)
def test_two_past_question(self):
"""
首页可能展示 多个 questions
"""
q1 = create_question(question_text="过去 问题 1", days=-30)
q2 = create_question(question_text="过去 问题 2", days=-5)
res = self.client.get(reverse('polls:index'))
self.assertQuerysetEqual(
res.context['latest_question_list'],
[q2, q1],
)
运行
(venv) E:PYTHON CODEmysite>
(venv) E:PYTHON CODEmysite>python manage.py test polls
Found 8 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
........
----------------------------------------------------------------------
Ran 8 tests in 0.030s
OK
Destroying test database for alias 'default'...
(venv) E:PYTHON CODEmysite>
3.投票-7自动化测试 业务逻辑
一个bug
发布日期时未来的那些投票不会在目录页 index 里出现,但是如果用户知道或者猜到正确的 URL ,还是可以访问到它们。所以我们得在 DetailView 里增加一些约束:
修复
加强限制,搜寻结果只返回时间小于当前的投票
# polls/views.py
class DetailView(generic.DetailView):
...
def get_queryset(self):
"""
Excludes any questions that aren't published yet.
"""
return Question.objects.filter(pub_date__lte=timezone.now())
测试用例
检验
# polls/tests.py
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)
3.投票-8应用的界面和风格
a 标签
新建 mysite/polls/static 目录 ,写入下面的文件
static/ #框架会从此处收集所有子应用静态文件 所以需要建一个新的polls目录区分不同应用
polls/ #所以写一个重复的polls很必要 否则Django直接使用找到的第一个style.css
style.css
定义 a 标签
# /style.css
li a{
color: green;
}
背景图
新建 images 目录
static/ #框架会从此处收集所有子应用静态文件 所以需要建一个新的polls目录区分不同应用
polls/
style.css
images/
bg.jpg
定义 背景
# /style.css
li a{
color: green;
}
body {
background: white url("images/bg.jpg") no-repeat;
}
效果
3.投票-9自定义后台表单
字段顺序
替换注释部分
# /mysite/polls/templates/admin.py
# admin.site.register(Question)
class QuestionAdmin(admin.ModelAdmin):
fields = ['question_text', 'pub_date'] # 列表里的顺序 表示后台的展示顺序
admin.site.register(Question,QuestionAdmin)
效果
字段集
当字段比较多时,可以把多个字段分为几个字段集
注意变量 fields 变为 fieldsets
class QuestionAdmin(admin.ModelAdmin):
#fields = ['question_text', 'pub_date'] # 列表里的顺序 表示后台的展示顺序
fieldsets = [
(None, {'fields': ['question_text']}),
('日期信息', {'fields': ['pub_date']}),
]
效果
关联选项
这样可以在创建 question 时 同时创建 choice
# /mysite/polls/templates/admin.py
效果
让卡槽更紧凑
替换 StackedInline 为 TabularInline
#class ChoiceInline(admin.StackedInline):
class ChoiceInline(admin.TabularInline):
model = Choice
extra = 3 # 默认有三个卡槽 后面还可以点击增加
效果
展示question的更多字段
Django默认返回模型的 str 方法里写的内容
添加字段 list_display 让其同时展示更多
方法was_published_recently
和他的返回内容 也可以当做字段展示
# mysite/polls/templates/admin.py
# class QuestionAdmin(admin.ModelAdmin):
# # fields = ['question_text', 'pub_date'] # 列表里的顺序 表示后台的展示顺序
# fieldsets = [
# (None, {'fields': ['question_text']}),
# ('日期信息', {'fields': ['pub_date']}),
# ]
# inlines = [ChoiceInline] # 引用模型
list_display = ('question_text', 'pub_date', 'was_published_recently')
效果 点击还可以按照该字段名排序
3.投票-9自定义后台表单-2
用装饰器优化 方法 的显示
方法 was_published_recently 默认用空格替换下划线展示字段
用装饰器优化一下
# /mysite/polls/templates/models.py
from django.contrib import admin # 装饰器
class Question(models.Model):
#....
@admin.display(
boolean=True,
ordering='pub_date',
description='最近发布的吗 ?',
)
def was_published_recently(self):
now = timezone.now()
# 发布时间距离现在不超过24小时 比现在小 比一天之前大 (即最近一天发布)
return (now - datetime.timedelta(days=1)) <= self.pub_date <= now
效果
添加过滤器
添加一个 list_filter 字段即可
# mysite/polls/templates/admin.py
# class QuestionAdmin(admin.ModelAdmin):
# # fields = ['question_text', 'pub_date'] # 列表里的顺序 表示后台的展示顺序
# fieldsets = [
# (None, {'fields': ['question_text']}),
# ('日期信息', {'fields': ['pub_date']}),
# ]
# inlines = [ChoiceInline] # 引用模型
# list_display = ('question_text', 'pub_date', 'was_published_recently')
list_filter = ['pub_date'] # 过滤器
效果
检索框
同上
#...
search_fields = ['question_text', 'pub_date'] # 检索框 可添加多个字段
效果
3.投票-10自定义后台风格界面
改掉 'Django 管理'
自定义工程模板(就是在manage.py的同级目录哪里)
再建一个templates
/mysite
/templates # 新建
修改 mysite/settings.py DIR是一个待检索路径 在django启动时加载
把所有模板文件存放在同一个templates中也可以 但分开会方便以后扩展复用代码
#...
# TEMPLATES = [
# {
# 'BACKEND': 'django.template.backends.django.DjangoTemplates',
#'DIRS': [],
'DIRS': [BASE_DIR / 'templates'],
# 'APP_DIRS': True,
# 'OPTIONS': {
# 'context_processors': [
# 'django.template.context_processors.debug',
# 'django.template.context_processors.request',
# 'django.contrib.auth.context_processors.auth',
# 'django.contrib.messages.context_processors.messages',
# ],
# },
# },
# ]
新建一个admin文件夹 复制 base_site.html 复制到里面
base_site.html 是django默认的模板 它存放在 django/contrib/admin/templates
的 admin/base_site.html
里面
可以用 ...> py -c "import django; print(django.__path__)"
命令查找源文件django位置
/mysite
/templates # 新建
/admin # 新建
base_site.html # 本地是到E:PYTHON CODEStudyBuddyvenvLibsite-packages
# djangocontribadmintemplatesadmin 复制
修改 base_site.html 内容
<!--{% extends "admin/base.html" %}-->
<!--{% block title %}{% if subtitle %}{{ subtitle }} | {% endif %}{{ title }} | {{ site_title|default:_('Django site admin') }}{% endblock %}-->
<!--{% block branding %}-->
<!--<h1 id="site-name"><a href="{% url 'admin:index' %}">{{ site_header|default:_('Django administration') }}</a></h1>-->
<h1 id="site-name"><a href="{% url 'admin:index' %}">投票 管理</a></h1>
<!--{% endblock %}-->
<!--{% block nav-global %}{% endblock %}-->
效果
注意,所有的 Django 默认后台模板均可被复写。若要复写模板,像你修改 base_site.html 一样修改其它文件——先将其从默认目录中拷贝到你的自定义目录,再做修改
当然 也可以用 django.contrib.admin.AdminSite.site_header 来进行简单的定制。
自定义 子应用 的模板
机智的同学可能会问: DIRS 默认是空的,Django 是怎么找到默认的后台模板的?因为 APP_DIRS 被置为 True,Django 会自动在每个应用包内递归查找 templates/ 子目录(不要忘了 django.contrib.admin 也是一个应用)。
我们的投票应用不是非常复杂,所以无需自定义后台模板。不过,如果它变的更加复杂,需要修改 Django 的标准后台模板功能时,修改 应用 的模板会比 工程 的更加明智。这样,在其它工程包含这个投票应用时,可以确保它总是能找到需要的自定义模板文件。
更多关于 Django 如何查找模板的文档,参见 加载模板文档。
自定义 后台 首页的模板
同之前base_site.html
复制 E:PYTHON CODEStudyBuddyvenvLibsite-packagesdjangocontribadmintemplatesadminindex.html
到mysite/templates/admin/index.html
直接修改
结束 撒花! :)
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