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我开始使用 Django，我有点卡在多模型领域，AKA Generic Relation (Content Type)

我有一个通用的内容类型“student_solution”，它可以属于：

  • 一个Org模型
  • 一个Institution模型
  • 一个Campus模型

因此，在这 3 个模型中的每一个模型中，我都有如下相反的关系models.py：

# Reverse generic relation - XXX See https://docs.djangoproject.com/en/dev/ref/contrib/contenttypes/#reverse-generic-relations
student_solutions = GenericRelation('student_solution.StudentSolution')

我不确定这是否是正确的方法，我认为是这样，但欢迎确认:)

它现在工作正常，但它在 Django 管理 UI 中不是用户友好的，查看它在 django admin 上的显示方式，创建学生解决方案时（我希望选择框显示一个label字段，而不是输入内容类型手动识别）：

django 管理员创建实体

创建 Org、Institution 或 Campus 时，该字段根本不会显示在 Django Admin 中（所以我可能配置错误）

我尝试了如何在管理内联中用带有实际对象的字段替换 content_type 和 object_id 字段？通过允许使用对象的标签选择正确的内容类型和“对象”来改进 UI。但此时它不起作用。

student_solution/models.py：

from django.contrib.contenttypes import fields
from django.contrib.contenttypes.models import ContentType
from django.db import models
from django.db.models import Q
from jsonfield import JSONField

from tfp_backoffice.apps.institution.models import Institution

CONTENT_TYPE_CHOICES = (
  Q(app_label='org', model='org') |
  Q(app_label='institution', model='institution') |
  Q(app_label='campus', model='campus')
)

class StudentSolution(models.Model):
  # Dynamic relationship to either Org, Institution or Campus entities
  # XXX https://simpleisbetterthancomplex.com/tutorial/2016/10/13/how-to-use-generic-relations.html
  content_type = models.ForeignKey(
    ContentType,
    on_delete=models.CASCADE,  # TODO check if good thing
    limit_choices_to=CONTENT_TYPE_CHOICES,
  )
  object_id = models.PositiveIntegerField()
  content_object = fields.GenericForeignKey(
    'content_type',
    'object_id'
  )

student_solution/admin.py：

from django.contrib import admin
from modeltranslation.admin import TranslationAdmin

from tfp_backoffice.apps.org.models import Org
from tfp_backoffice.apps.student_solution.forms import StudentSolutionAdminForm, GenericStudentSolutionOwnerChoicesFieldForm
from tfp_backoffice.apps.student_solution.models import StudentSolution

    
class StudentSolutionInlineAdmin(admin.TabularInline):
  form = GenericStudentSolutionOwnerChoicesFieldForm
  model = Org  # TODO not sure at all about that, should be either of 3 related ContentTypes (Org | Institution | Campus)
  # This throw error "<class 'tfp_backoffice.apps.student_solution.admin.StudentSolutionInlineAdmin'>: (admin.E202) 'org.Org' has no ForeignKey to 'student_solution.StudentSolution'."


class StudentSolutionAdmin(TranslationAdmin):
  form = StudentSolutionAdminForm
  inlines = [
    StudentSolutionInlineAdmin,
  ]


admin.site.register(StudentSolution, StudentSolutionAdmin)

student_solution/forms.py：

from django import forms
from django.contrib.contenttypes.models import ContentType

from tfp_backoffice.apps.org.models import Org
from tfp_backoffice.apps.student_solution.models import CONTENT_TYPE_CHOICES, StudentSolution


class StudentSolutionAdminForm(forms.ModelForm):
  class Meta:
    model = StudentSolution
    fields = '__all__'  # Keep all fields    

class GenericStudentSolutionOwnerChoicesFieldForm(forms.ModelForm):
  ct_place_type = ContentType.objects.get_for_model(Org)  # TODO not sure at all about that, should be either of 3 related ContentTypes (Org | Institution | Campus)

  object_id = forms.ModelChoiceField(
    Org.objects.all(),
    limit_choices_to=CONTENT_TYPE_CHOICES,
    label='Student solution'
  )
  content_type = forms.ModelChoiceField(
    ContentType.objects.all(),
    initial=ct_place_type,  
    limit_choices_to=CONTENT_TYPE_CHOICES,  # should I use this here?
    widget=forms.HiddenInput()
  )

  def clean_object_id(self):
    return self.cleaned_data['object_id'].pk

  def clean_content_type(self):
    return self.ct_place_type

但是此代码不起作用并在启动服务器时引发此错误

django.core.management.base.SystemCheckError: SystemCheckError: 系统检查发现了一些问题：

<class 'tfp_backoffice.apps.student_solution.admin.StudentSolutionInlineAdmin'>: (admin.E202) 'org.Org' has no ForeignKey to 'student_solution.StudentSolution'.

4

2 回答 2

4

如果我理解您想要正确执行的操作，您应该StudentSolutionInlineAdmin在每个 、 和 admins 中都有您的Org，Institution它Campus应该是GenericTabularInline（https://docs.djangoproject.com/en/2.2/ref/contrib/contenttypes/#管理中的通用关系）。

所以你会在（例如）你的org/admin.py：

from django.contrib import admin
from django.contrib.contenttypes.admin import GenericTabularInline
from django import forms

from .models import Org
from student_solution.models import StudentSolution

class StudentSolutionInlineAdmin(GenericTabularInline):
    model = StudentSolution
    extra = 1

class StudentSolutionAdminForm(forms.ModelForm):
    class Meta:
        model = StudentSolution
        fields = '__all__'  # Keep all fields 

@admin.register(Org)
class OrgAdmin(admin.ModelAdmin):
    form = StudentSolutionAdminForm
    inlines = [StudentSolutionInlineAdmin]

这将允许您在管理员中添加与 an 相关的OrgStudentSolution Org。

于 2019-09-09T20:25:02.603 回答
0

You could have a look on this one: https://docs.djangoproject.com/en/2.2/ref/contrib/contenttypes/#generic-relations-in-admin

They have special inline types to use if you are using the content type feature framework

于 2019-08-31T20:48:14.730 回答