python - 自定义 unique_together 键名

Question

我有一个带有 unique_together 的模型定义为 3 个字段一起唯一:

class MyModel(models.Model):
    clid = models.AutoField(primary_key=True, db_column='CLID')
    csid = models.IntegerField(db_column='CSID')
    cid = models.IntegerField(db_column='CID')
    uuid = models.CharField(max_length=96, db_column='UUID', blank=True)

    class Meta(models.Meta):
        unique_together = [
            ["csid", "cid", "uuid"],
        ]

现在，如果我尝试使用现有 csid+cid+uuid 组合保存 MyModel 实例，我会得到:

IntegrityError: (1062, "Duplicate entry '1-1-1' for key 'CSID'")

这是正确的。但是，有没有办法自定义那个键名？ (本例中为CSID)

换句话说，我可以为 unique_together 中列出的约束提供一个名称吗？

^{据我了解，这不在文档中。}

Answer 1

它没有很好的文档记录，但取决于您使用的是 Django 1.6 还是 1.7，有两种方法可以做到这一点:

In Django 1.6 you can override the unique_error_message, like so :

class MyModel(models.Model):
    clid = models.AutoField(primary_key=True, db_column='CLID')
    csid = models.IntegerField(db_column='CSID')
    cid = models.IntegerField(db_column='CID')

    # ....

def unique_error_message(self, model_class, unique_check):
    if model_class == type(self) and unique_check == ("csid", "cid", "uuid"):
        return _('Your custom error')
    else:
        return super(MyModel, self).unique_error_message(model_class, unique_check)

Or in Django 1.7 :

class MyModel(models.Model):
    clid = models.AutoField(primary_key=True, db_column='CLID')
    csid = models.IntegerField(db_column='CSID')
    cid = models.IntegerField(db_column='CID')
    uuid = models.CharField(max_length=96, db_column='UUID', blank=True)

    class Meta(models.Meta):
        unique_together = [
            ["csid", "cid", "uuid"],
        ]
        error_messages = {
            NON_FIELD_ERRORS: {
                'unique_together': "%(model_name)s's %(field_labels)s are not unique.",
            }
        }