基于Pydantic封装的通用模型在API请求验证中的应用详解

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# @author: hui
# @Desc: { 通用的一些Pydantic模型 }
# @Date: 2023/03/30 11:57
from pydantic import BaseModel, Field, validator
from typing import Optional
from datetime import date


class DateModel(BaseModel):
    """日期模型"""

    start_date: Optional[date] = Field(None, description="开始日期")
    end_date: Optional[date] = Field(None, description="结束日期")

    @validator("end_date", always=True)
    def validate_end_date(cls, end_date, values):
        start_date = values.get("start_date")
        if all([start_date, end_date]) and end_date < start_date:
            raise ValueError("结束日期必须大于等于开始日期")
        return end_date


class OrderModel(BaseModel):
    """排序模型"""

    order_by: Optional[str] = Field(None, description="排序字段,逗号分隔")
    order_mode: Optional[str] = Field(None, description="排序方式,逗号分隔,asc升序desc降序")

    @validator("order_by", "order_mode", always=True)
    def split_comma_separated_string(cls, value):
        if value:
            return value.split(",")
        return value

    @validator("order_mode", always=True)
    def check_length(cls, order_mode, values):
        order_by = values.get("order_by")
        if order_by and order_mode and len(order_by) != len(order_mode):
            raise ValueError("order_by and order_mode must have the same length")
        return order_mode


class PageModel(BaseModel):
    """分页模型"""

    page: Optional[int] = Field(default=1, ge=1, description="页码")
    page_size: Optional[int] = Field(default=10, le=1000, description="每页数量, 默认10，最大1000")

class DateOrderModelMixin(DateModel, OrderModel):
    """日期与排序模型Mixin"""
    pass

class PageOrderModel(BaseModel):
    """分页排序模型"""
    order_model: OrderModel = Field(OrderModel(), description="排序模型")
    page_model: PageModel = Field(PageModel(), description="分页模型")
    def __init__(self, **data):
        if "order_model" in data and "page_model" in data:
            order_model = data.pop("order_model", None)
            page_model = data.pop("page_model", None)
        else:
            # 用于直接平铺的字典入参
            order_params = {
                "order_by": data.pop("order_by", None),
                "order_mode": data.pop("order_mode", None),
            }
            page_params = {
                "page": data.pop("page", None),
                "page_size": data.pop("page_size", None),
            }
            order_model = OrderModel(**order_params)
            page_model = PageModel(**page_params)
        super().__init__(order_model=order_model, page_model=page_model, **data)
page_order = PageOrderModel(
    order_model=OrderModel(order_by="field1,field2", order_mode="asc,desc"),
    page_model=PageModel(page=1, page_size=10)
)
>>>out
order_model=OrderModel(order_by=['field1', 'field2'], order_mode=['asc', 'desc'])
page_model=PageModel(page=1, page_size=10)
req_params = {
    "order_by": "field1,field2",
    "order_mode": "asc,desc",
    "page": 1,
    "page_size": 10
}
req_model = PageOrderModel(**req_params)
>>>out
order_model=OrderModel(order_by=['field1', 'field2'], order_mode=['asc', 'desc'])
page_model=PageModel(page=1, page_size=10)

from pydantic import BaseModel, Field
from typing import Optional

class ProductQueryModel(DateOrderModelMixin):
    product_category: Optional[str] = Field(None, description="商品类别")


class OrderQueryModel(PageOrderModel):
    customer_id: Optional[int] = Field(None, description="客户ID")


# 使用 ProductQueryModel 进行参数验证
product_query_params = {
    "start_date": "2023-04-01",
    "end_date": "2023-04-30",
    "order_by": "price",
    "order_mode": "desc",
    "product_category": "Electronics"
}

product_query = ProductQueryModel(**product_query_params)

>>>out
order_by=['price'] order_mode=['desc'] start_date=datetime.date(2023, 4, 1) end_date=datetime.date(2023, 4, 30) product_category='Electronics'


# 使用 OrderQueryModel 进行参数验证
order_query_params = {
    "start_date": "2023-04-01",
    "end_date": "2023-04-30",
    "order_by": "order_date",
    "order_mode": "asc",
    "page": 1,
    "page_size": 20,
    "customer_id": 12345
}

order_query = OrderQueryModel(**order_query_params)

>>>out
order_model=OrderModel(order_by=['order_date'], order_mode=['asc']) page_model=PageModel(page=1, page_size=20) customer_id=12345

type Address struct {
    Street string
    City   string
    State  string
    Zip    string
}

type Person struct {
    Name    string
    Age     int
    Address Address
}