更改另一个字段时如何修改pydantic字段？

Question

我有一个 pydantic 类，例如：

from pydantic import BaseModel
class Programmer(BaseModel):
    python_skill: float
    stackoverflow_skill: float
    total_score: float = None

现在我正在根据其他字段计算 total_score：

@validator("total_score", always=True)
def calculat_total_score(cls, v, *, values):
    return values.get("python_skill") + values.get("stackoverflow_skill")

这很好用，但是现在当我更改其中一项技能时：

programmer = Programmer(python_skill=1.0, stackoverflow_skill=9.0)
print(programmer.total_score) # return 10.0
programmer.python_skill=2.0 
print(programmer.total_score) # still return 10.0

我希望 total_score 自动更新。

任何解决方案？TNX！！

Answer 1

您可以为此使用根验证器。每次更新后都会调用它。像这样：

from pydantic import BaseModel, validator, root_validator


class Programmer(BaseModel):
    python_skill: float
    stackoverflow_skill: float
    total_score: float = None

    class Config:
        validate_assignment = True

    @root_validator
    def calculate_total_score(cls, values):
        values["total_score"] = values.get("python_skill") + values.get("stackoverflow_skill")
        return values


programmer = Programmer(python_skill=1.0, stackoverflow_skill=9.0)
print(programmer.total_score)  # 10.0
programmer.python_skill = 2.0
print(programmer.total_score)  # 11.0

注意：1.7.3之前的版本有bug，建议更新