How can i set max string field length constraint in pydantic?

Question

So, i have pydantic model with string field

class MyPydanticModel(BaseModel):
    name: Optional[str]

And i want make max length for this field is 10. How can i do this?

Answer 1

You can use constr:

from pydantic import BaseModel, constr

class MyPydanticModel(BaseModel):
    name: Optional[constr(max_length=10)]