django自定义管理器带过滤参数 [英] django custom manager with filter parameter
问题描述
我想添加一个可以从模板调用的自定义管理器,但不会影响整个模型(例如管理员视图),哪些监听请求中设置的参数(user_profile)。
以下是我到目前为止:
models.py:
def current(self):
return self.filter(id = 1)##这个简化的过滤器测试工作..
class CurrentManager(models.Manager):
use_for_related_fields = True
def get_query_set(self):
return CurrentQuerySet(self.model)
def current (self,* args,** kwargs):
return self.get_query_set()。current(* args,** kwargs)
对于模型B定义:
objects = CurrentManager()
模板调用:
{%for a in a.b_set.current%}
但是,一旦我尝试将参数传递给该过滤器(在这种情况下,存储在用户配置文件中的日期),该方法不会返回任何结果。
例如:
models.py
class CurrentQuerySet(models.query.QuerySet):
pre>
def current(self,my_date):
return self.filter(valid_from__lte = my_date)
showA.html
{%for b in a。 b_set.current(request.user.get_profile.my_date)%}
不要将参数从模板,我也试图在view.py中设置这个。
@login_required
pre>
def showA(request,a_id )
my_date = request.user.get_profile()。my_date
a = A.objects.get(id = a_id)
t = loader.get_template('myapp / showA.html')
c = RequestContext(request,{'a':a,'my_date':my_date,})
return HttpResponse(t.render(c))
我在哪里缺少(或误会)哪一部分?
谢谢
R
编辑
这里的模型。如上所述,在这个例子中,这是一个简单的1:n关系,但在其他情况下也可以是m:n。
class A(models.Model):
#objects = CurrentManager()
a = models.CharField(max_length = 200)
description = models.TextField(null = True,blank = True)
valid_from = models.DateField('valid from')
valid_to = models.DateField('valid to',null = True,blank = True)
def __unicode __(self):
return self.a
class B(models.Model):
#objects = models.Manager()
objects = CurrentManager()
a = models.ForeignKey( A)
b = models.CharField(max_length = 200)
screenshot = models.ManyToManyField(Screenshot,through =ScreenshotToB)
description = models.TextField(null = True,blank = true)
valid_from = models.DateField('valid from')
valid_to = models.DateField('valid to',null = True,blank = True)
def __unicode __(self) :
返回self.b
Edit-2
接受的答案至少可以用于一个关系。
如果有更嵌套的数据模型,这种方法似乎没有提供预期的结果:
models.py
class C(models.Model):
objects = CurrentManager()
b = models.ForeignKey(A)
c = models.CharField(max_length = 200)
description = models.TextField(null = True,blank = True)
valid_from = models.DateField('valid从')
valid_to = models.DateField('valid to',null = True,blank = True)
def __unicode __(self):
return self.c
views.py
@login_required
def showA(request,a_id):
a = A.objects.get(id = a_id)
my_date = request.user.get_profile()。my_date
b_objects = a.b_set.current(my_date)
c_objects = b_objects.c_set.current(my_date)
t = loader.get_template('controltool2 / showA.html')
c = RequestContext(request,{'a':a,'b_objects':b_objects,'c_objects':c_objects,})
return HttpResponse t.render(c))
这将返回错误:'QuerySet'对象没有属性'c_set '
解决方案我会简化:
code class class CurrentManager(models.Manager)
def current(self,my_date):
return super(CurrentManager,self).get_query_set()。filter(valid_from__lte = my_date)
然后使用它:
a = A.objects.get(id = a_id)
my_date = request.user.get_profile().my_date
b_objects = a.b_set.objects.current(my_date )
然后只将传递给模板作为使用以下访问它们的过滤对象:
{b_objects中的b为%}
希望这有帮助!
编辑(请求者):
我必须按照以下方法进行调整工作:
a = A.objects.get(id = a_id)
my_date = request.user.get_profile ).my_date
b_objects = a.b_set.current(my_date)
这会抛出一个错误:'RelatedManager'对象没有属性'objects'
a.b_set.objects.current(my_date)
I would like to add a custom manager which can be called from a template, but does not affect the entire model (e.g. admin views) and which listens to a parameter set in the request (user_profile).
The following is what I have so far:
models.py:
class CurrentQuerySet(models.query.QuerySet): def current(self): return self.filter(id=1) ## this simplified filter test works.. class CurrentManager(models.Manager): use_for_related_fields = True def get_query_set(self): return CurrentQuerySet(self.model) def current(self, *args, **kwargs): return self.get_query_set().current(*args, **kwargs)
For model B is defined:
objects = CurrentManager()
The template calls:
{% for b in a.b_set.current %}
But as soon as I try to pass a parameter to that filter (in this case a date stored on the user-profile) the method does not return any results.
e.g.:
models.py
class CurrentQuerySet(models.query.QuerySet): def current(self,my_date): return self.filter(valid_from__lte=my_date)
showA.html
{% for b in a.b_set.current(request.user.get_profile.my_date) %}
Instead of passing the parameter from the template, I have also tried to set this in the view.py
@login_required def showA(request,a_id): my_date = request.user.get_profile().my_date a = A.objects.get(id=a_id) t = loader.get_template('myapp/showA.html') c = RequestContext(request,{'a':a,'my_date':my_date,}) return HttpResponse(t.render(c))
Which part am I missing (or misunderstanding) here?
Thanks
R
Edit
Here the models. As mentioned, in this example it's a simple 1:n relationship, but can also be m:n in other cases.
class A(models.Model): #objects = CurrentManager() a = models.CharField(max_length=200) description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.a class B(models.Model): #objects = models.Manager() objects = CurrentManager() a = models.ForeignKey(A) b = models.CharField(max_length=200) screenshot = models.ManyToManyField("Screenshot",through="ScreenshotToB") description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.b
Edit-2
The accepted answer works for at least one relationship.
In case of a more nested data model, this method seems not to deliver the expected results:models.py
class C(models.Model): objects = CurrentManager() b = models.ForeignKey(A) c = models.CharField(max_length=200) description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.c
views.py
@login_required def showA(request,a_id): a = A.objects.get(id=a_id) my_date = request.user.get_profile().my_date b_objects = a.b_set.current(my_date) c_objects = b_objects.c_set.current(my_date) t = loader.get_template('controltool2/showA.html') c = RequestContext(request,{'a':a,'b_objects':b_objects,'c_objects':c_objects,}) return HttpResponse(t.render(c))
This returns the error: 'QuerySet' object has no attribute 'c_set'
解决方案I'd simplify it:
class CurrentManager(models.Manager): def current(self, my_date): return super(CurrentManager, self).get_query_set().filter(valid_from__lte=my_date)
and then use it like this:
a = A.objects.get(id=a_id) my_date = request.user.get_profile().my_date b_objects = a.b_set.objects.current(my_date)
and then just pass a to the template as the filtered objects accessing them using this:
{% for b in b_objects %}
Hope this helps!
Edit (by requestor):
I had to adjust it as follows to get it working:
a = A.objects.get(id=a_id) my_date = request.user.get_profile().my_date b_objects = a.b_set.current(my_date)
This threw an error: "'RelatedManager' object has no attribute 'objects'"
a.b_set.objects.current(my_date)
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