数据查询操作

Posted 2020-10-06 看雪。

一、模型类

class ArticleManager(models.Manager):
    def archive(self, **kwargs):
        l = []
        month_list = []
        for i in self.filter(**kwargs).values("create_time"):

            date = i[‘create_time‘]
            month_list.append(date.month)
            t = date.strftime("%Y-%m-%d")

            if t not in l:
                l.append(t)
        blog_age = str(len(set(month_list))) + "个月"
        return l,blog_age


class UserInfo(AbstractUser):
    """
    用户信息
    """
    nid = models.BigAutoField(primary_key=True)
    nickname = models.CharField(verbose_name=‘昵称‘, max_length=32)
    telephone = models.CharField(max_length=11, blank=True, null=True, unique=True, verbose_name=‘手机号码‘)
    avatar = models.FileField(verbose_name=‘头像‘, upload_to=‘./upload/avatar/‘)
    create_time = models.DateTimeField(verbose_name=‘创建时间‘, auto_now_add=True)

    fans = models.ManyToManyField(verbose_name=‘粉丝们‘,
                                  to=‘UserInfo‘,
                                  through=‘UserFans‘,

                                  through_fields=(‘user‘, ‘follower‘))

    def __str__(self):
        return self.username


class UserFans(models.Model):
    """
    互粉关系表
    """
    nid = models.AutoField(primary_key=True)
    user = models.ForeignKey(verbose_name=‘博主‘, to=‘UserInfo‘, to_field=‘nid‘, related_name=‘users‘)
    follower = models.ForeignKey(verbose_name=‘粉丝‘, to=‘UserInfo‘, to_field=‘nid‘, related_name=‘followers‘)

    class Meta:
        unique_together = [
            (‘user‘, ‘follower‘),
        ]


class Blog(models.Model):
    """
    博客信息
    """
    nid = models.BigAutoField(primary_key=True)
    title = models.CharField(verbose_name=‘个人博客标题‘, max_length=64)
    site = models.CharField(verbose_name=‘个人博客后缀‘, max_length=32, unique=True)
    theme = models.CharField(verbose_name=‘博客主题‘, max_length=32)
    user = models.OneToOneField(to=‘UserInfo‘, to_field=‘nid‘)

    def __str__(self):
        return self.title


class Category(models.Model):
    """
    博主个人文章分类表
    """
    nid = models.AutoField(primary_key=True)
    title = models.CharField(verbose_name=‘分类标题‘, max_length=32)

    blog = models.ForeignKey(verbose_name=‘所属博客‘, to=‘Blog‘, to_field=‘nid‘)

    def __str__(self):
        return self.title


class Article(models.Model):
    nid = models.BigAutoField(primary_key=True)
    title = models.CharField(max_length=50, verbose_name=‘文章标题‘)
    desc = models.CharField(max_length=255, verbose_name=‘文章描述‘)
    read_count = models.IntegerField(default=0)
    comment_count = models.IntegerField(default=0)
    up_count = models.IntegerField(default=0)
    down_count = models.IntegerField(default=0)
    category = models.ForeignKey(verbose_name=‘文章类型‘, to=‘Category‘, to_field=‘nid‘, null=True)
    create_time = models.DateTimeField(verbose_name=‘创建时间‘, auto_now_add=True)
    blog = models.ForeignKey(verbose_name=‘所属博客‘, to=‘Blog‘, to_field=‘nid‘)
    tags = models.ManyToManyField(
        to="Tag",
        through=‘Article2Tag‘,
        through_fields=(‘article‘, ‘tag‘),
    )

    type_choices = [
        (1, "Python"),
        (2, "Linux"),
        (3, "OpenStack"),
        (4, "GoLang"),
    ]

    article_type_id = models.IntegerField(choices=type_choices, default=None)
    objects = ArticleManager()

    def __str__(self):
        return self.title


#
class ArticleDetail(models.Model):
    """
    文章详细表
    """
    nid = models.AutoField(primary_key=True)
    content = models.TextField(verbose_name=‘文章内容‘, )

    article = models.OneToOneField(verbose_name=‘所属文章‘, to=‘Article‘, to_field=‘nid‘)

    def __str__(self):
        return self.article.title


class Comment(models.Model):
    """
    评论表
    """
    nid = models.BigAutoField(primary_key=True)
    article = models.ForeignKey(verbose_name=‘评论文章‘, to=‘Article‘, to_field=‘nid‘)
    content = models.CharField(verbose_name=‘评论内容‘, max_length=255)
    create_time = models.DateTimeField(verbose_name=‘创建时间‘, auto_now_add=True)

    parent_id = models.ForeignKey(‘self‘, blank=True, null=True, verbose_name=‘父级评论‘)
    user = models.ForeignKey(verbose_name=‘评论者‘, to=‘UserInfo‘, to_field=‘nid‘)

    up_count = models.IntegerField(default=0)


class ArticleUpDown(models.Model):
    """
    点赞表
    """
    nid = models.AutoField(primary_key=True)
    user = models.ForeignKey(‘UserInfo‘, null=True)
    article = models.ForeignKey("Article", null=True)
    UporDown = models.BooleanField(verbose_name=‘是否赞‘,default=False)


class CommentUp(models.Model):
    """
    点赞表
    """
    nid = models.AutoField(primary_key=True)
    user = models.ForeignKey(‘UserInfo‘, null=True)
    comment = models.ForeignKey("Comment", null=True)


class Tag(models.Model):
    nid = models.AutoField(primary_key=True)
    title = models.CharField(verbose_name=‘标签名称‘, max_length=32)
    blog = models.ForeignKey(verbose_name=‘所属博客‘, to=‘Blog‘, to_field=‘nid‘)

    def __str__(self):
        return self.title


class Article2Tag(models.Model):
    nid = models.AutoField(primary_key=True)
    article = models.ForeignKey(verbose_name=‘文章‘, to="Article", to_field=‘nid‘)
    tag = models.ForeignKey(verbose_name=‘标签‘, to="Tag", to_field=‘nid‘)

    class Meta:
        unique_together = [
            (‘article‘, ‘tag‘),
        ]

二、数据查询

　　前提，前端传来文章的作者名。　　

def blog(request, name):
    userinfo = UserInfo.objects.filter(username=name).first()
    if not userinfo:
        return render(request,‘404.html‘)
    currentblog = Blog.objects.filter(user=userinfo).first() # 过滤出当前作者的博客  正向查询
    artcle_list = Article.objects.filter(blog=currentblog)  ＃　查询出该博客所有文章　　正向查询
    catagory_list = Category.objects.filter(blog=currentblog)　＃　查询出该博客所有分类　正常查询　　一对多关系

    # 查询所有分类对应文章的数量

    # 方式一
    ret = []
    for catagory in catagory_list:
        tmp = []
        tmp.append(catagory)
        tmp.append(catagory.article_set.all().count())

    # 方式二
    catagory_count = artcle_list.values_list("category__title").annotate(Count("nid")) # 统计每个分类的文章数目，反向查询

    # 标签对应文章的数目
    tag_list = Tag.objects.filter(blog=currentblog)

    # 方式一
    res = []
    for tag in tag_list:
        temp = []
        tmp.append(tag.title)
        tmp.append(artcle_list.filter(tags__title=tag.title).count())
        res.append(tmp)

    # 方式二
    tag_cout = artcle_list.values_list("tags__title").annotate(Count(‘nid‘))

    # 文章按时间分类
    ress1,blog_age = Article.objects.archive(blog=currentblog)

    return render(request, ‘homesite.html‘, {"userinfo": userinfo,‘catagory_count‘:catagory_count,
                                             ‘tag_cout‘:tag_cout,‘ress1‘:ress1,‘blog_age‘:blog_age,
                                             })

三、前端显示

　　后台查询到的数据，通过模板语言渲染后，显示在前端！