python实战----博客系统(完善)

摘要：上一篇博客系统的博客还没有实现评论，按标签搜索按日期搜索按分类搜索的功能，这篇博客主要是对以上功能的增加。博客首页修改主页的文件有关分页显示的部分上一页上一页第页共页下一页下一页

上一篇‘博客系统’的博客还没有实现评论，按标签搜索、按日期搜索、按分类搜索的功能，这篇博客主要是对以上功能的增加。

第一步：新建app:comment，在主setting.py中添加新app,修改主urls.py文件

from django.conf.urls import url, include
from django.contrib import admin

urlpatterns = [
    url(r"^admin/", admin.site.urls),
    url(r"",include("blog.urls")),
    url(r"",include("comments.urls")),

]

第二步：编写评论的数据库表单

from django.contrib.auth.models import User
from django.db import models

# Create your models here.
from blog.models import Post


class Comment(models.Model):
    user =models.ForeignKey(User,verbose_name="用户")
    email = models.EmailField(verbose_name="电子邮箱")
    text = models.TextField(max_length=255,verbose_name="评论正文")
    # auto_now_add=True 自动create_time为最新一次更改评论信息的时间
    create_time = models.DateTimeField(auto_now_add=True,verbose_name="创建时间")
    post = models.ForeignKey(Post)
    class Meta:
        verbose_name = "评论"
        verbose_name_plural = "评论"

    def __str__(self):
        return  self.text[:4]

第三步：编写评论的路由comment.urls.py和comment.views.py

# comment.views.py
from django.shortcuts import render, get_object_or_404,redirect

# Create your views here.
from blog.models import Post
from comments.forms import CommentForm


def post_comment(request, id):
    # 1. 获取用户选择的博客
    post = get_object_or_404(Post, id=id)
    # 2. 如果用户提交评论
    if request.method == "POST":
        print(request.POST)
        form = CommentForm(request.POST)
        # 2.1 判断表单是否合法
        if form.is_valid():
            comment = form.save(commit=False)
            comment.post = post
            comment.save()
        # 2.2 如果不合法，则提交错误信息
        else:
            return render(request, "blog/detail.html",
                          context={
                              "errors": form.errors
                          })
    # 3. 如果不是POST请求，访问用户详情页
    return redirect(post.get_url())

# comment.urls
from django.conf.urls import url, include
from django.contrib import admin

from comments import views

app_name = "comment"
urlpatterns = [
    url(r"^comment/blog/(?Pd+)/$",views.post_comment,name="post_comment"),
]

第四步：编写评论表单

# 同步与数据库评论的形式
from comments.models import Comment


class CommentForm(forms.ModelForm):
    class Meta:
        model = Comment
        fields = ["user","email","text"]

第五步：修改HTML文件中关于评论的部分

                        

                        
发表评论
                        

                            {% csrf_token %}
                            

                                

                                    {{ form.user.label }}
                                    {{ form.user }}
                                
                                

                                    {{ form.email.label }}
                                    {{ form.email }}
                                
                                

                                    {{ form.text.label }}
                                    {{ form.text }}
                                    发表
                                
                            
    
                        
                        

                            
评论列表，共 {{ comments.count }} 条评论
                            

                                {% for comment in comments %}
                                    

                                        {{ comment.user }}
                                        {{ comment.create_time }}
                                        

                                            {{ comment.text }}
                                        
                                    
                                {% endfor %}

                            
                        
                    

实现按标签搜索、按日期搜索、按分类搜索的功能

第一步：自定义标签

准备(必需)工作：

在某个app下创建一个名为templatetags(必需，且包名不可变)的包。假设我们在名为blog的app下创建了一个templatetags的包，并在该包下创建了一个名为blog_tags的文件.
 确保settings文件中的INSTALLD_APPS内必须含有该app
 修改setting.py有关时间显示的部分

# TIME_ZONE = "UTC"
TIME_ZONE = "Asia/Shanghai"

USE_I18N = True

USE_L10N = True

#如果setting中配置USE_TZ=True则输出的是UTC时间（naive time），
# 如果setting中配置USE_TZ=False，则该输出时间与datetime.datetime.now()完全相同
# USE_TZ = True
USE_TZ = False

2. 接下来在blog_tags文件中写入如下几行

from django import template

register = template.Library()

 3. 在模板中使用{% load %} 标签装载自定义标签或者装饰器

from django import template
from django.db.models import Count

from blog.models import Post, Category, Tag

register = template.Library()

@register.simple_tag
def get_recent_posts(num=3):
    return Post.objects.all().order_by("-create_time")[:num]


@register.simple_tag
def archives():

    return Post.objects.dates(field_name="create_time",
                              kind="month",
                              order="DESC")

@register.simple_tag
def get_category():
    return Category.objects.annotate(num_posts=Count("post")).filter(num_posts__gt=0)


@register.simple_tag
def get_tags():
    # return Tag.objects.all()
    return Tag.objects.annotate(num_posts = Count("post"))

第二步： 编写标签查找的路由和视图函数

路由

#blog.urls.py
from django.conf.urls import url

from django.contrib import admin

from blog import views

app_name = "blog"
urlpatterns = [
    url(r"^$", views.index, name="index"),
    url(r"blog/(?Pd+)/$", views.detail, name="detail"),
    url(r"^archive/(?Pd{4})/(?Pd{1,2})/", views.archive, name="archive"),
    url(r"^category/(?Pd+)/", views.category, name="category"),
    url(r"^tag/(?Pd+)/", views.tag, name="tag"),
    url(r"^search", views.search, name="search")
]

视图函数

from django.db.models import Q
from django.http import HttpResponse
from django.shortcuts import render, get_object_or_404

# Create your views here.
from markdown import markdown

from blog.models import Post, Tag
from comments.forms import CommentForm


def index(request):
    # return HttpResponse("ok index!")
    posts = Post.objects.all()
    return render(request,"blog/index.html",context={
        "posts":posts
    })
def detail(request,id):
    # return HttpResponse("ok,%s detail" %(id))
    post = Post.objects.get(id=id)
    post.add_views()
    form = CommentForm()
    comments = post.comment_set.all()
    post.body = markdown(post.body,
                         extensions=["markdown.extensions.extra",
                                     "markdown.extensions.codehilite",
                                     "markdown.extensions.toc", ],
                         output_format="html")
    return render(request,"blog/detail.html",context={
        "post":post,
        "comments":comments,
        "form":form,
    })
def archive(request,year,month):
    posts = Post.objects.filter(
        create_time__year=year,
        create_time__month=month
    ).order_by("-create_time")

    return  render(request,"blog/index.html",context={
        "posts":posts
    })


def category(request,id):
    posts = Post.objects.filter(category_id=id)
    return render(request,"blog/index.html",
                  context={
                      "posts":posts

                  })


def tag(request,id):
    tag = get_object_or_404(Tag,id=id)
    posts = Post.objects.filter(tags=tag).order_by("-create_time")
    return render(
        request, "blog/index.html",
        context={
            "posts": posts

        }


    )


def search(request):
    query = request.GET.get("query",None)
    posts = Post.objects.filter(
        Q(title__icontains=query) |
        Q(body__icontains=query)
    )

    if not posts:
        return render(request,"blog/index.html",
                      context={
                          "posts":posts,
                          "message":"没有找到相关信息"
                      }
                      )
    else:
        return render(request, "blog/index.html",
                      context={
                          "posts": posts

                      }
                      )

第三步：修改Html文件，仅截取部分代码

这里在博客详情页需要显示的是博客的结构(目录)，添加显示目录的代码
修改视图函数

def detail(request,id):
    # return HttpResponse("ok,%s detail" %(id))
    post = Post.objects.get(id=id)
    post.add_views()
    form = CommentForm()
    comments = post.comment_set.all()
    # post.body = markdown(post.body,
    #                      extensions=["markdown.extensions.extra",
    #                                  "markdown.extensions.codehilite",
    #                                  "markdown.extensions.toc", ],
    #                      output_format="html")
    md = Markdown(
        extensions=["markdown.extensions.extra",
                    "markdown.extensions.codehilite",
                    "markdown.extensions.toc", ],
        output_format="html"
    )
    # Convert markdown to serialized XHTML or HTML.
    post.body = md.convert(post.body)
    post.toc = md.toc
    return render(request,"blog/detail.html",context={
        "post":post,
        "comments":comments,
        "form":form,

    })

右侧导航栏

{#     基模板       #}

   

详情页添加博客目录

{# blog/detail.html #}
{% block toc %}
    
文章目录
        {{ post.toc | safe }}
    
{% endblock %}

按类别查找

按标签查找

按时间查找

显示博客目录

Django提供了一个新的类来帮助你管理分页数据，这个类存放在django/core/paginator.py.它可以接收列表、元组或其它可迭代的对象。

def index(request):
    all_posts = Post.objects.count()
    if all_posts % PER_PAGE != 0:
        page_nums = all_posts // PER_PAGE + 1
    else:
        page_nums = all_posts // PER_PAGE
    paginator = Paginator(Post.objects.all(),PER_PAGE)
    if  request.GET.get("page"):
        page = request.GET.get("page")
    else:
        page = 1
    try:
        posts = paginator.page(page)
    except (PageNotAnInteger,EmptyPage):
        posts = paginator.page(1)

        posts.has_previous()
        posts.has_next()
        posts.previous_page_number()
        posts.next_page_number()


    return render(request, "blog/index.html",
                  context={
        "title":"博客首页",
        "posts":posts,
        "pages_num":page_nums,
    })

修改主页的html文件有关分页显示的部分

  

            {% if posts.has_previous %}
                上一页
            {% else %}
                上一页

            {% endif %}


            第 {{ posts.number }} 页 / 共 {{ pages_num }} 页

            {% if posts.has_next %}
                下一页

            {% else %}
                下一页