python - Django : inclure un champ de clé primaire dans un enregistrement de M2M inline - Stack Overflow

I have a Product model that includes an M2M reference to an Option model, using an intermediate model, OptionPrice, which lets me override the base values of the option with product-specific values.

here are the three models:

    #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class Product(models.Model):
    productid = UUIDField(db_column='ProductID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    productname = models.CharField(db_column='ProductName', max_length=100, verbose_name='name', default='') 
    slug = AutoSlugField(populate_from='productname',unique=True, max_length=100, always_update=True)
    productnumber = models.CharField(db_column='ProductNumber', blank=True, max_length=50, null=True, verbose_name='number', default='') 
    cost = models.DecimalField(decimal_places=4, max_digits=19, db_column='Cost', default=0) 
    priceperitem = models.DecimalField(decimal_places=4, max_digits=19, db_column='PricePerItem', verbose_name='price per item', default=0) 
    onspecial = models.BooleanField(db_column='OnSpecial', verbose_name='on special', default=False) 
    discount = models.FloatField(null=True, db_column='Discount', blank=True, verbose_name='discounted', default=0) 

    #connections to other models
    options = models.ManyToManyField(Option, null=True, through='OptionPrice', verbose_name='product options', blank=True) 
    optiongroups = models.ManyToManyField(OptionGroup, null=True, verbose_name='product option groups', blank=True) 

    package = models.ForeignKey(ShippingPackage, verbose_name='shipping container', default=1) 
    categories = models.ManyToManyField(Category, verbose_name='product categories') 
    cross_sell = models.ManyToManyField('Product', verbose_name='cross-sell items', blank=True) 


#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class Option(models.Model):
    optionid = UUIDField(db_column='OptionID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    title = models.CharField(db_column='Title', max_length=500) 
    price = models.DecimalField(decimal_places=4, max_digits=19, db_column='Price') 
    pricemodstyle = models.CharField(db_column='PriceModStyle', max_length=50, verbose_name='price modification style', choices=PRICE_MOD_CHOICES) 
    displayrank = models.IntegerField(db_column='DisplayRank', verbose_name='sort order') 
    optiongroup = models.ForeignKey('OptionGroup', verbose_name='option group') 



#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class OptionPrice(models.Model):
    optionpriceid = UUIDField(db_column='OptionPriceID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    option = models.ForeignKey(Option)
    product = models.ForeignKey(Product)
    price = models.DecimalField(decimal_places=4, max_digits=19, db_column='Price') 
    pricemodstyle = models.CharField(db_column='PriceModStyle', max_length=50, verbose_name='price modification style', choices=PRICE_MOD_CHOICES) 

, and for the admin.py, I have the product options defined as being inline

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class ProductAdmin(ImportExportModelAdmin):
    resource_class = ProductResource
    model=Product
    ordering = ['categories__categoryname','productname']
    save_on_top = True
    save_as = True
    inlines = [OptionPriceAdminInline]

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class OptionPriceAdminInline(admin.TabularInline):
    model=OptionPrice
    extra = 0
    save_on_top = True

My issue is that when I load a product in the administrator, the inlines show up beautifully, with every field represented except the primary key (optionpriceid). Consequently, the first time I add options to this product, they save properly (new id is created automagically). If I then attempt to reload the product and edit the saved options, I get a MultiValueDictKeyError because these inlined items don't actually have their primary key values included in the rows emitted by the admin.

What am I doing wrong?

The issue turned out to be a django bug, solved by this pull request. The problem is that I was using a custom UUIDField as the primary key - to quote the ticket:

It seems to be that this this problem happens for models which have a primary key field that is not based on the AutoField (such as a CharField).

When the primary key field is not based on an AutoField 'has_auto_field' is not set to True, therefore it will not output the primary key in the form.

I have a Product model that includes an M2M reference to an Option model, using an intermediate model, OptionPrice, which lets me override the base values of the option with product-specific values.

here are the three models:

    #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class Product(models.Model):
    productid = UUIDField(db_column='ProductID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    productname = models.CharField(db_column='ProductName', max_length=100, verbose_name='name', default='') 
    slug = AutoSlugField(populate_from='productname',unique=True, max_length=100, always_update=True)
    productnumber = models.CharField(db_column='ProductNumber', blank=True, max_length=50, null=True, verbose_name='number', default='') 
    cost = models.DecimalField(decimal_places=4, max_digits=19, db_column='Cost', default=0) 
    priceperitem = models.DecimalField(decimal_places=4, max_digits=19, db_column='PricePerItem', verbose_name='price per item', default=0) 
    onspecial = models.BooleanField(db_column='OnSpecial', verbose_name='on special', default=False) 
    discount = models.FloatField(null=True, db_column='Discount', blank=True, verbose_name='discounted', default=0) 

    #connections to other models
    options = models.ManyToManyField(Option, null=True, through='OptionPrice', verbose_name='product options', blank=True) 
    optiongroups = models.ManyToManyField(OptionGroup, null=True, verbose_name='product option groups', blank=True) 

    package = models.ForeignKey(ShippingPackage, verbose_name='shipping container', default=1) 
    categories = models.ManyToManyField(Category, verbose_name='product categories') 
    cross_sell = models.ManyToManyField('Product', verbose_name='cross-sell items', blank=True) 


#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class Option(models.Model):
    optionid = UUIDField(db_column='OptionID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    title = models.CharField(db_column='Title', max_length=500) 
    price = models.DecimalField(decimal_places=4, max_digits=19, db_column='Price') 
    pricemodstyle = models.CharField(db_column='PriceModStyle', max_length=50, verbose_name='price modification style', choices=PRICE_MOD_CHOICES) 
    displayrank = models.IntegerField(db_column='DisplayRank', verbose_name='sort order') 
    optiongroup = models.ForeignKey('OptionGroup', verbose_name='option group') 



#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class OptionPrice(models.Model):
    optionpriceid = UUIDField(db_column='OptionPriceID', editable=False, primary_key=True, auto=True, hyphenate=True) 
    option = models.ForeignKey(Option)
    product = models.ForeignKey(Product)
    price = models.DecimalField(decimal_places=4, max_digits=19, db_column='Price') 
    pricemodstyle = models.CharField(db_column='PriceModStyle', max_length=50, verbose_name='price modification style', choices=PRICE_MOD_CHOICES) 

, and for the admin.py, I have the product options defined as being inline

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class ProductAdmin(ImportExportModelAdmin):
    resource_class = ProductResource
    model=Product
    ordering = ['categories__categoryname','productname']
    save_on_top = True
    save_as = True
    inlines = [OptionPriceAdminInline]

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class OptionPriceAdminInline(admin.TabularInline):
    model=OptionPrice
    extra = 0
    save_on_top = True

My issue is that when I load a product in the administrator, the inlines show up beautifully, with every field represented except the primary key (optionpriceid). Consequently, the first time I add options to this product, they save properly (new id is created automagically). If I then attempt to reload the product and edit the saved options, I get a MultiValueDictKeyError because these inlined items don't actually have their primary key values included in the rows emitted by the admin.

What am I doing wrong?

The issue turned out to be a django bug, solved by this pull request. The problem is that I was using a custom UUIDField as the primary key - to quote the ticket:

It seems to be that this this problem happens for models which have a primary key field that is not based on the AutoField (such as a CharField).

When the primary key field is not based on an AutoField 'has_auto_field' is not set to True, therefore it will not output the primary key in the form.

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