Django与字段和自身的众多关系具有独特的共同关系

Question

I'm try create post with language and content, and relate it on other versions of same page, but I'm get stuck

class Page(models.Model):
    content = models.TextField()
    language = models.CharField(max_length=7, choices=settings.LANGUAGES)
    versions = models.ManyToManyField('self', blank=True)
    class Meta:
        unique_together = ('language', 'versions',)

This will not work properly, because Django not allow make "unique" ManyToMany fields.

Then I'm try make same relationship trough related model:

class VersionsPage(models.Model):
    pass
    # ToDo: add unique together here,  to foreign key field

class Page(models.Model):
    ...
    versions = models.ManyToManyField('self', blank=True, through="VersionsPage")

Anyone know how to make that without using symmetrical=False?

Answer 1

I think you are looking for something like this:

class Page(models.Model):
    pass

class PageVersion(models.Model):
    page = models.ForeignKey(Page, related_name='versions')
    content = models.TextField()
    language = models.CharField(max_length=7, choices=settings.LANGUAGES)

    class Meta:
        unique_together = ('page', 'language',)


#getting all page versions:
page = Page.objects.get(pk=some_id)
versions = page.versions.all()