python - 如何在 Django View 中将用户登录字段与其他用户进行比较

Question

假设我有以下模型:

import ephem

class Person(models.Model):
        username = models.ForeignKey(User, blank=False)
        slug = models.SlugField(blank=False)
        location = ForeignKey(Location, blank=True) # return longitude & latitude city from Pyephem library
        city = models.CharField(max_length=255, blank=False, default='')

        def __str__(self):
            return self.username

        def get_city(self):
           city = ephem.Observer()
           city.lon = float(self.location.longitude)
           city.lat = float(self.location.latitude)
           return city # return city from location field

        def save(self, *args, **kwargs):
            if not self.pk:
                self.slug = slugify(self.username)
            super(Person, self).save(*args, **kwargs)

如何在 django 的 View 中以编程方式比较登录用户的属性和属性的其他用户？这是基于 slug 的用户名字段，还有一个来自其他 python 库 (Pyephem) 的附加对象，如下所示:

def detail(request, slug):
    instance = Person.objects.all()
    city = ........ # City from city fields at Person model, the city's value from current user logged have their value as city0 and city's values for other user have value as city1, city2, city3 Et seq...

    for distance in instance:            
        # if current user logged are visiting other user detail then compare them each other
        do something for city0 and city1, city0 and city2, city0 and city3 Et seq....
            distance = ... # calculate distance of city's user logged & city's other user
        # I'm not sure what to do in this area so it will get the results of comparing between attribute of current user logged and attribute of other user

        return render(
        request, "detail.html",
        {
            'distance': distance,
        }
    )

*更新

我根据@cezar 的回答更新了上面的模型并添加了城市的功能:

Answer 1

根据我的了解，很可能许多用户在您的模型中得到了一个 slug。因此，如果您想比较已登录的用户和带有一些 slug 的用户组，我会生成 QuerySet，然后进行迭代。

def detail(request, slug=None):
    instances = Person.objects.filter(slug=slug)

    if instances.count() == 0:
        return HttpResponse('Slug returns 0 matches')
    else:
        for object in instances:
            do something for city0 and city1

---

好的，感谢您提供更多详细信息!现在更新后我认为 request.user 对象就是你要找的:

def calculate_distance(user1, user2):
    #do something here like:
    #user1.location.lat user2.location.long etc.
    return distance_between

def detail(request, slug=None):
    instance = Person.objects.get(slug=slug)
    observer_user = request.user

    #added below variable to clarify code
    user_to_be_observed = instance

    return calculate_distance(observer_user, user_to_be_observed)