python - django 导入导出不适用于 mptt

Question

我在尝试让导入导出适用于 mptt 模型时遇到问题。这是我的代码:

models.py

from django.db import models
from mptt.models import MPTTModel, TreeForeignKey

class MyModel(MPTTModel):
    name = models.CharField(max_length=255)
    parent = TreeForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, related_name='children')
    active = models.BooleanField(default=True,null=False,blank=False)
    sort_order = models.PositiveIntegerField(default=0,null=True,blank=True)

    class MPTTMeta:
        order_insertion_by = ['name']

    class Meta:
        ordering = ['sort_order']

    def __str__(self):
        return self.name

admin.py

from django.contrib import admin
from mptt.admin import MPTTModelAdmin, DraggableMPTTAdmin
from .models import MyModel
from import_export import resources
from import_export.admin import ImportExportModelAdmin, ImportExportMixin

class MyModelResource(resources.ModelResource):

    class Meta:
        model = MyModel
        exclude = ('lft','rght','tree_id','level')

@admin.register(MyModel)
class MyModelAdmin(ImportExportMixin, DraggableMPTTAdmin):
    resource_class = MyModelResource
    list_display = ('tree_actions','indented_title','active','sort_order')
    list_editable = ('active','sort_order')
    list_display_links = ('indented_title',)

当我导出时，它将名称字段放在父列中。当我再次导入时，它在父字段上失败:

"MyModel.parent" must be a "MyModel" instance.

非常感谢任何帮助

Answer 1

我遇到了同样的问题，并按照博丹的问题设法解决了这个问题:Django call 'id' expected a number but got string 。以下是我为使其发挥作用所做的工作:

模型.py

from django.db import models
from mptt.models import MPTTModel, TreeForeignKey

# Create your models here.

class Category(MPTTModel):
    name        = models.CharField(max_length = 120, unique = True)
    parent      = TreeForeignKey('self', on_delete = models.CASCADE, null = True, blank = True, related_name = "children")

    class MPTTMeta: 
        order_insertion_by = ['name']

    class Meta: 
        verbose_name_plural = 'categories'

    def __str__(self):
        return self.name

admin.py

from django.contrib import admin
from mptt.admin import DraggableMPTTAdmin, TreeRelatedFieldListFilter
from import_export import resources, fields, widgets

from import_export.admin import ImportExportModelAdmin
from .models import Category

# Resource Classes
class CategoryResource(resources.ModelResource):

    parent = fields.Field(
        column_name='parent',
        attribute='parent',
        widget = widgets.ForeignKeyWidget(Category, 'name'))

    class Meta: 
        model = Category
        skip_unchanged = True
        report_skipped = True
        exclude = ('id',)
        import_id_fields = ('name',)
        fields = ('parent','name','lft','rght','tree_id','level')

# Admin Classes

@admin.register(Category)
class CategoryAdmin(ImportExportModelAdmin,DraggableMPTTAdmin):
    resource_class = CategoryResource

所以在你的情况下，我相信你的领域是:

fields = ('parent','name','active','sort_order','lft','rght','tree_id','level')

似乎我们需要排除“id”键，但我不完全确定为什么。我注意到，当我导入模型以前没有见过的类别名称时，它会自行配置 mptt 结构。

我正在使用 Django 3.0.7、django-mptt 0.11.0 和 django-import-export 2.2.0。我是堆栈溢出的新手，因此如果这不是正确的响应方式，我深表歉意，但我希望它能有所帮助!