Django 查询集按字段排序

Question

i'm using django 2 and in my list view i want to oder the queryset by likecount and datetime field. The main goal is to odering the post with mostlikes for today. Like, i want to show the most liked posts for today. It's like todays top 10 post(mostliked) . i have tried many ways but can't figure it out. I hope you guys can help me.

My models.py:

class post(models.Model):
    parent = models.ForeignKey("self", on_delete=models.CASCADE, blank=True, null=True)
    title = models.CharField(max_length=100)
    image = models.ImageField(upload_to='post_pics', null=True, blank=True)
    content = models.TextField()
    likes = models.ManyToManyField(User, related_name='likes', blank=True)
    date_posted = models.DateTimeField(default=timezone.now)
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    restrict_comments = models.BooleanField(default=False)
    watchlist = models.ManyToManyField(User, related_name='watchlist', blank=True)

    def __str__(self):
        return self.content

    class Meta:
        ordering = ['-date_posted', 'title']

    def get_absolute_url(self):
        return reverse ('blog-home')

    def total_likes(self):
        return self.likes.count()

My views.py:

@login_required
def most_likes(request):
    posts = post.objects.annotate(like_count=Count('likes')).order_by('-like_count', '-date_posted')
    context = {'posts': posts}

    return render(request, 'blog/most_likes.html', context)

Answer 1

If I'm getting you right, you are already ordering your queryset by the fields you want ( like_count and date_posted ), but you're still missing the part of getting only the results for a desired time period.

If this is the case, then what you're missing is to filter the queryset. You would need something like this (to get the posts of the last 10 days, ordered by their date and likes count):

import datetime as dt


@login_required
def most_likes(request):
    delta = dt.timedelta(days=10)
    posts = post.objects.filter(date_posted__gt=(dt.datetime.now() - delta)) \
        .annotate(like_count=Count('likes')).order_by('-like_count', '-date_posted')
    context = {'posts': posts}

    return render(request, 'blog/most_likes.html', context)

Now, I would try to pass the value of the desired time period I want to filter the data as a query parameter, so I can do something as the following:

delta = dt.timedelta(days=request.GET.get('days'))