# 昨日知识点回顾
编辑条目及创建用户账户
暂没能解决bug：
The view learning_logs.views.edit_entry didn't return an HttpResponse object. It returned None instead.
# 今日知识点学习
19.2.5 注销
提供让用户注销的途径
1.在base.html中添加注销链接
# base.html
<p>
<a href = "{% url 'learning_logs:index' %}">Learning Log</a> -
<a href = "{% url 'learning_logs:topics' %}">Topics</a> -
{% if user.is_authenticated %}
Hello, {{ user.username }}.
<a href="{% url 'users:logout' %}">Log out</a>
{% else %}
<a href="{% url 'users:login' %}">Log in </a>
{% endif %}
</p>
{% block content %}{% endblock content %}2.注销确认页面
# learning_log\users\templates\registration\logged_out.html
{% extends "learning_logs/base.html" %}
{% block content %}
<p>You have been logged out. Thank you for visiting!</p>
{% endblock content %}
19.2.6 注册页面
1.注册页面的URL模式
# users\urls.py
"""为应用程序users定义URL模式"""
from django.urls import path, include
from . import views
app_name = 'users'
urlpatterns = [
# 包含默认的身份验证URL
path('', include('django.contrib.auth.urls')),
# 注册页面
path('register/', views.register, name='register')
]
2.视图函数register()
# # users\views.py
from django.shortcuts import render, redirect
from django.contrib.auth import login
from django.contrib.auth.forms import UserCreationForm
# Create your views here.
def register(request):
"""注册新用户"""
if request.method != 'POST':
# 显示空的注册表单
form = UserCreationForm()
else:
# 处理填写好的表单
form = UserCreationForm(data=request.POST)
if form.is_valid():
new_user = form.save()
# 让用户自动登录，再重定向主页
login(request, new_user)
return redirect('learning_logs:index')
# 显示空表单或指出表单无效
context = {'form': form}
return render(request, 'registration/register.html', context)
3.注册模版
# users\templates\registration\register.html
{% extends "learning_logs/base.html" %}
{% block content %}
<form method='post' action="{% url 'users:register' %}" >
{% csrf_token %}
{{ form.as_p }}
<button name="submit">Register</button>
<input type="hidden" name="next"
value="{% url 'learning_logs:index' %}" />
</form>
{% endblock content %}4.链接到注册页面
# base.html
<p>
<a href = "{% url 'learning_logs:index' %}">Learning Log</a> -
<a href = "{% url 'learning_logs:topics' %}">Topics</a> -
{% if user.is_authenticated %}
Hello, {{ user.username }}.
<a href="{% url 'users:logout' %}">Log out</a>
{% else %}
<a href="{% url 'users:register' %}">Register </a>-
<a href="{% url 'users:login' %}">Log in </a>
{% endif %}
</p>
{% block content %}{% endblock content %}19.3 让用户拥有自己的数据
19.3.1 使用@login_required限制访问
装饰器：放在函数定义前面的指令，能在函数运行前修改函数代码
1.限制访问显示所有主题的页面
# learning_logs/views.py
from django.shortcuts import render, redirect
from django.contrib.auth.decorators import login_required
# 导入所需数据相关联的模型
from .models import Topic, Entry
from .forms import TopicForm, EntryForm
# Create your views here.
def index(request):
"""学习笔记的主页"""
# 传递两个实参：对象request以及一个可用于创建页面的模版
return render(request, 'learning_logs/index.html')
@login_required
def topics(request):
"""显示所有的主题"""
topics = Topic.objects.order_by('date_added')
---snip---# settings.py
---snip(直到末尾）---
# 我的设置
LOGIN_URL = 'users:login'2.全面限制对项目“学习笔记”的访问
# learning_logs\views.py
from django.shortcuts import render, redirect
from django.contrib.auth.decorators import login_required
# 导入所需数据相关联的模型
from .models import Topic, Entry
from .forms import TopicForm, EntryForm
# Create your views here.
def index(request):
"""学习笔记的主页"""
# 传递两个实参：对象request以及一个可用于创建页面的模版
return render(request, 'learning_logs/index.html')
@login_required
def topics(request):
"""显示所有的主题"""
topics = Topic.objects.order_by('date_added')
# 定义一个将要发送模版的上下文
context = {'topics': topics}
return render(request, 'learning_logs/topics.html', context)
@login_required
def topic(request, topic_id):
"""显示单个主题"及所有的条目"""
topic = Topic.objects.get(id=topic_id)
entries = topic.entry_set.order_by('-date_added')
context = {'topic': topic, 'entries': entries}
return render(request, 'learning_logs/topic.html', context)
@login_required
def new_topic(request):
"""添加新主题"""
if request.method != 'POST':
# 未提交数据：创建一个新表单
form = TopicForm()
else:
# POST提交的数据：对数据进行处理
form = TopicForm(data=request.POST)
if form.is_valid():
form.save()
return redirect('learning_logs:topics')
# 显示空表单后指出表单数据无效
context = {'form': form}
return render(request, 'learning_logs/new_topic.html', context)
@login_required
def new_entry(request, topic_id):
"""在特定主题中添加新条目"""
topic = Topic.objects.get(id=topic_id)
if request.method != 'POST':
# 未提交数据：创建一个空表单
form = EntryForm()
else:
# POST提交的数据：对数据进行处理
form = EntryForm(data=request.POST)
if form.is_valid():
new_entry = form.save(commit=False)
new_entry.topic = topic
new_entry.save()
return redirect('learning_logs:topic', topic_id=topic_id)
# 显示空表单或支出表单数据无效
context = {'topic': topic, 'form': form}
return render(request, 'learning_logs/new_entry.html', context)
@login_required
def edit_entry(request, entry_id):
"""编辑既有条目"""
entry = Entry.objects.get(id=entry_id)
topic = entry.topic
if request.method != 'POST':
# 初次请求：使用当前条目填充表单
form =EntryForm(instance=entry)
else:
# POST提交的数据：对数据进行处理
form = EntryForm(instance=entry, data=request.POST)
if form.is_valid():
form.save()
return redirect('learning_logs:topic', topic_id=topic.id)
context = {'entry': entry, 'topic': topic, 'form': form}
return render(request, 'learning_logs/edit_entry.html', context)19.3.2 将数据关联到用户
1.修改模型Topic
# models.py
from django.db import models
from django.contrib.auth.models import User
# Create your models here.
class Topic(models.Model):
"""用户学习的主题"""
# 存储少量文本如名称、标题或城市，预留200字符空间
text = models.CharField(max_length=200)
# 记录日期和时间的数据，为True自动设置为当前日期和时间
date_added = models.DateTimeField(auto_now_add=True)
owner = models.ForeignKey(User, on_delete=models.CASCADE)
def __str__(self):
"""返回模型的字符串表示"""
# 只显示条目前50字符，省略号指出显示的并非整个条目
return f"{self.text[:50]}..."
class Entry(models.Model):
"""学到某个主题的具体知识"""
topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
# 外键(foreign key)是一个数据库术语，它指向数据库另一条记录。
# 次联删除：on_delete=models.CASCADE让Django在删除主题的同时删除所有与之相关联的条目
text = models.TextField()
date_added = models.DateTimeField(auto_now_add=True)
class Meta:
# 存储用于管理模型的额外信息
verbose_name_plural = 'entries'2. 确定当前有哪些用户
3.迁移数据库
重建数据库：python manage.py flush
19.3.3 只允许用户访问自己的主题
# views.py
---snip---
@login_required
def topics(request):
"""显示所有的主题"""
topics = Topic.objects.filter(owner=request.user).order_by('date_added')
# 定义一个将要发送模版的上下文
context = {'topics': topics}
return render(request, 'learning_logs/topics.html', context)
---snip---19.3.4 保护用户的主体
# views.py
from django.shortcuts import render, redirect
from django.contrib.auth.decorators import login_required
from django.http import Http404
---snip---
@login_required
def topic(request, topic_id):
"""显示单个主题"及所有的条目"""
topic = Topic.objects.get(id=topic_id)
# 确认请求的主题属于当前用户
if topic.owner != request.user:
raise Http404
---snip---19.3.5 保护页面edit_entry
# views.py
---snip---
@login_required
def edit_entry(request, entry_id):
"""编辑既有条目"""
entry = Entry.objects.get(id=entry_id)
topic = entry.topic
if topic.owner != request.user:
raise Http404
---snip---19.3.6 将新主题关联到当前用户
# views.py
---snip---
@login_required
def new_topic(request):
"""添加新主题"""
if request.method != 'POST':
# 未提交数据：创建一个新表单
form = TopicForm()
else:
# POST提交的数据：对数据进行处理
form = TopicForm(data=request.POST)
if form.is_valid():
new_topic = form.save(commit=False)
new_topic.owner = request.user
new_topic.save()
return redirect('learning_logs:topics')
# 显示空表单后指出表单数据无效
context = {'form': form}
return render(request, 'learning_logs/new_topic.html', context)
---snip---