from pydantic import BaseModel, Field

class Pagination(BaseModel):
    """通用分页与过滤模型"""
    page: int = Field(default=1, ge=1, description="当前页码")
    page_size: int = Field(default=30, ge=1, le=100, description="每页条数")
    
    def to_dict(self):
        """过滤掉 None 值，转化为 API 要求的字典"""
        return {k: v for k, v in self.model_dump().items() if v is not None}