Django Admin 通用内容类型多模型内联表单

Question

我刚开始使用 Django，但我有点卡在多模型领域，AKA Generic Relation（内容类型）

我有一个通用的内容类型“student_solution”，它可以属于：

• Org 模型
• Institution 模型
• Campus 模型

因此，在这 3 个模型中，我在每个 models.py 中都有如下相反的关系：

# 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，我想是的，但欢迎确认:)

---

它现在工作正常，但在 Django 管理 UI 中不是用户友好的，请查看它在 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 label 字段，而不是手动输入内容类型 ID）：

在创建 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）

我尝试关注How to replace content_type and object_id fields by a field with actual object in admin inline?，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。但目前不起作用。

---

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

但是这段代码不起作用并在启动服务器时抛出这个错误

django.core.management.base.SystemCheckError: SystemCheckError: 系统检查发现一些问题：

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

Answer 1

如果我理解您想要正确执行的操作，您应该在每个 Org、Institution 和 Campus 管理员中都有您的 StudentSolutionInlineAdmin，它应该是 GenericTabularInline (https://docs.djangoproject.com/en/2.2/ref/contrib/contenttypes/#generic-relations-in-admin )。

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]

这将允许您从 Org 管理员中添加与 Org 相关的 StudentSolution。

Answer 2

你可以看看这个：https://docs.djangoproject.com/en/2.2/ref/contrib/contenttypes/#generic-relations-in-admin

如果您使用的是内容类型功能框架，它们有特殊的内联类型可供使用