我想在项目类中添加项目类

Question

最终的 JSON 将是：

            "address": ----,
            "state": ----,
            year: {
                "first": ----,
                "second": {
                    "basic": ----,
                    "Information": ----,
                    }
            },

我想创建我的 items.py 像（只是示例）：

class Item(scrapy.Item): 
  address = scrapy.Field()
  state = scrapy.Field()
  year = scrapy.Field(first), scrapy.Field(second)

class first(scrapy.Item):
  amounts = scrapy.Field()

class second(scrapy.Item):
  basic = scrapy.Field()
  information = scrapy.Field()

这个怎么实现，已经查过了https://doc.scrapy.org/en/latest/topics/items.html#extending-items

how to implement nested item in scrapy?

但是没有关于这个概念的线索......有什么建议吗？

Answer 1

class Item(scrapy.Item): 
  address = scrapy.Field()
  state = scrapy.Field()
  year = scrapy.Field(serializer=dict)

class Year(scrapy.Item):
  first = scrapy.Field(serializer=dict)
  second = scrapy.Field(serializer=dict)

class first(scrapy.Item):
  amounts = scrapy.Field()

class second(scrapy.Item):
  basic = scrapy.Field()
  information = scrapy.Field()

这样你就可以做到：

>>> b = second(basic="hello", information="hello world")
>>> a = first(amounts=3)
>>> year = Year(first=a, second=b)
>>> year
{'first': {'amounts': 3},
 'second': {'basic': 'hello', 'information': 'hello world'}}
>>> item = Item(address='address value', state='state value', year=year)
>>> item
{'address': 'address value',
 'state': 'state value',
 'year': {'first': {'amounts': 3}, 'second': {'basic': 'hello', 'information': 'hello world'}}}

Answer 2

class Item(scrapy.Item): 
  address = scrapy.Field()
  state = scrapy.Field()
  year = scrapy.Field(first), scrapy.Field(second)    #You dont need to do like this

class first(scrapy.Item):
  amounts = scrapy.Field()     #this work and below

class second(scrapy.Item):    #and yes this work, you can do it in spider level or pipelines, just make your desired data, and pas it to year variable as you want. it will accumulate that
  basic = scrapy.Field()
  information = scrapy.Field()

让我举个例子，

first = {'first': first}
second = {'basic': basic, 'info': info}

year = {'first': first, 'second': second}