TypeError __str__ 返回非字符串（int 类型）

Question

I'm trying to code a screenplay app, but I'm running into a problem when I actually add information to my model. My models look like this:

class Screenplay(models.Model):
    uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    title = models.CharField(max_length=100)
   
    def __str__(self):
        return self.title

class Block(models.Model):
    class BlockTypes(models.IntegerChoices):
        HEADING = 1, 'HEADING'
        DESCRIPTION = 2, 'DESCRIPTION'
        CHARACTER = 3, 'CHARACTER'
        DIALOGUE = 4, 'DIALOGUE' 

    uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    text = models.TextField()
    type = models.PositiveSmallIntegerField(
        choices=BlockTypes.choices,
        default=BlockTypes.HEADING
    )
    screenplay = models.ForeignKey(Screenplay, on_delete=models.CASCADE, related_name='blocks')
    
    def __str__(self):
        return self.type

When I go to my backend api (localhost:8000/api/screenplays) I see my sample screenplays which resemble this:

HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

[
    {
        "uuid": "SAMPLE - UUID",
        "title": "SAMPLE - TITLE",
        "blocks": []
    },
]

The error I posted in the title pops up when I actually add a block to a screenplay. In my api it seems like "blocks": [] but when I POST a block to a certain screenplay it breaks. I just don't understand what the issue really is, if it's in my models.py or in some other part of my django app. Do I need to add a blocks in my Screenplay model? Anyways, any advice would be great at this point.

Answer 1

__str__ must return string and you are returning integer ie PositiveSmallIntegerField . Convert that value to string in your Block model as

def __str__(self):
    return str(self.type)

More details onstr [Django-doc]