Schema circular import error

[thatsaw]

Hi! Thanks for the amazing library.

I have UserSchema:

# users/models.py
class User(AbstractUser):
    ...


# users/schemas.py
from typing import List
from tasks.schemas import TaskSchema

class UserSchema(ModelSchema):
    tasks: List[TaskSchema] = []

    class Config:
        model = User
        ...

...and TaskSchema:

# tasks/models.py
class Task(models.Model):
    ...
    owner = models.ForeignKey(User, related_name="tasks", on_delete=models.CASCASE)


# tasks/schemas.py
from users.schemas import UserSchema

class TaskSchema(ModelSchema):
    owner: UserSchema

    class Config:
        model = Task
        ...

But it throws:

ImportError: cannot import name 'TaskSchema' from partially initialized module 'tasks.schemas' (most likely due to a circular import) (/Users/myname/codes/django/ninja-api/tasks/schemas.py)

---

What I want to do is that I want to fetch:

1. GET /api/todos - a list of tasks with related owners
2. GET /api/todos/{task_id} - a task with owner
3. GET /api/users/{user_id} - a user with a list of owned tasks

---

Versions:

python = ^3.11
django = ^4.1.5
django-ninja = ^0.20.0

---

Please let me know if you need more information.

Similar to #154

[paqstd-dev]

# users/schemas.py
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from tasks.schemas import TaskSchema

Maybe this will help?

[baseplate-admin]

and modify the main code like this

# users/models.py
class User(AbstractUser):
    ...


# users/schemas.py
from typing import List
from tasks.schemas import TaskSchema

class UserSchema(ModelSchema):
    tasks: List["TaskSchema"] = [] # modify this

    class Config:
        model = User
        ...