1from plain import models
 2
 3
 4@models.register_model
 5class Session(models.Model):
 6    session_key = models.CharField(max_length=40)
 7    session_data = models.JSONField(default=dict, required=False)
 8    created_at = models.DateTimeField(auto_now_add=True)
 9    expires_at = models.DateTimeField(allow_null=True)
10
11    class Meta:
12        indexes = [
13            models.Index(fields=["expires_at"]),
14        ]
15        constraints = [
16            models.UniqueConstraint(fields=["session_key"], name="unique_session_key")
17        ]
18
19    def __str__(self):
20        return self.session_key