露出＆QUOT;虚拟＆QUOT;在tastypie视野？ [英] Exposing "virtual" field in a tastypie view?

问题描述

我想用tastypie公开相同类型的某些对象来创建一个视图，但具有下列<打击>两个三捻：

I want to create a view using tastypie to expose certain objects of the same type, but with the following two three twists:

1. 我需要使用三个单独的查询对象;
2. 我需要添加一种对底层模型中存在的字段，并且该字段的值取决于它来自查询;和
3. 在该数据将每个用户的（所以我需要挂钩到的是得到一个请求的方法之一）。

我不清楚如何挂钩到tastypie生命周期，以实现这一目标。推荐的方法添加一个虚拟字段中的脱水方法，只知道捆绑它的经营上。

I'm not clear on how to hook into the tastypie lifecycle to accomplish this. The recommended way for adding a "virtual" field is in the dehydrate method, which only knows about the bundle it's operating on.

更糟糕的是，有加入查询集没有正式的办法。

Even worse, there's no official way to join querysets.

我的问题会消失，如果我能得到tastypie接受的东西比一个QuerySet等。在这种情况下，我可以通过它我对象的子类列表，与其他字段添加。

My problem would go away if I could get tastypie to accept something other than a queryset. In that case I could pass it a list of subclasses of my object, with the additional field added.

我接受任何其他合理的解决方案。

I'm open to any other sensible solution.

编辑：增加扭转3 - 每个用户的数据。

Added twist 3 - per-user data.

推荐答案

好了，这是我的解决方案。 code是如下。

OK, so this is my solution. Code is below.

注意要点：

1. 的工作基本都在 obj_get_list 完成。这就是我跑我的查询，其访问请求。
2. 我可以返回从 obj_get_list 列表。
3. 我可能会覆盖所有其他 OBJ _相当于其他操作（如 obj_get * 方法， obj_create 等），如果我想他们是可用的。
4. 因为我没有一个查询集在元，我需要提供一个 object_class 来告诉tastypie的自省哪些领域提供。
5. 要揭露我的虚拟属性（我在创建 obj_get_list ），我需要添加一个字段声明吧。
6. 在我注释掉的过滤器和授权限制，因为我不需要他们现在。我需要实现他们自己，如果我需要他们。

1. The work is basically all done in obj_get_list. That's where I run my queries, having access to the request.
2. I can return a list from obj_get_list.
3. I would probably have to override all of the other obj_* methods corresponding to the other operations (like obj_get, obj_create, etc) if I wanted them to be available.
4. Because I don't have a queryset in Meta, I need to provide an object_class to tell tastypie's introspection what fields to offer.
5. To expose my "virtual" attribute (which I create in obj_get_list), I need to add a field declaration for it.
6. I've commented out the filters and authorisation limits because I don't need them right now. I'd need to implement them myself if I needed them.

code：

from tastypie.resources import ModelResource
from tastypie import fields
from models import *
import logging

logger = logging.getLogger(__name__)


class CompanyResource(ModelResource):
    role = fields.CharField(attribute='role')


    class Meta:
        allowed_methods = ['get']
        resource_name = 'companies'
        object_class = CompanyUK
        # should probably have some sort of authentication here quite soon


    #filters does nothing. If it matters, hook them up
    def obj_get_list(self, request=None, **kwargs):
#         filters = {}

#         if hasattr(request, 'GET'):
#             # Grab a mutable copy.
#             filters = request.GET.copy()

#         # Update with the provided kwargs.
#         filters.update(kwargs)
#         applicable_filters = self.build_filters(filters=filters)

        try:
            #base_object_list = self.get_object_list(request).filter(**applicable_filters)
            def add_role(role):
                def add_role_company(link):
                    company = link.company
                    company.role = role
                    return company
                return add_role_company

            director_of = map(add_role('director'), DirectorsIndividual.objects.filter(individual__user=request.user))
            member_of   = map(add_role('member'),   MembersIndividual.objects.filter(individual__user=request.user))
            manager_of  = map(add_role('manager'),  CompanyManager.objects.filter(user=request.user))

            base_object_list = director_of + member_of + manager_of
            return base_object_list #self.apply_authorization_limits(request, base_object_list)
        except ValueError, e:
            raise BadRequest("Invalid resource lookup data provided (mismatched type).")

这篇关于露出＆QUOT;虚拟＆QUOT;在tastypie视野？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！