allow spiders to return dicts instead of Items

In many cases the requirement to define and yield Items from a spider is an unnecessary complication.

An example from Scrapy tutorial:

import scrapy

class DmozItem(scrapy.Item):
    title = scrapy.Field()
    link = scrapy.Field()
    desc = scrapy.Field()

class DmozSpider(scrapy.Spider):
    name = "dmoz"
    allowed_domains = ["dmoz.org"]
    start_urls = [
        "http://www.dmoz.org/Computers/Programming/Languages/Python/Books/",
        "http://www.dmoz.org/Computers/Programming/Languages/Python/Resources/"
    ]

    def parse(self, response):
        for sel in response.xpath('//ul/li'):
            item = DmozItem()
            item['title'] = sel.xpath('a/text()').extract()
            item['link'] = sel.xpath('a/@href').extract()
            item['desc'] = sel.xpath('text()').extract()
            yield item

It can be made simpler with dicts instead of Items:

import scrapy

class DmozSpider(scrapy.Spider):
    name = "dmoz"
    allowed_domains = ["dmoz.org"]
    start_urls = [
        "http://www.dmoz.org/Computers/Programming/Languages/Python/Books/",
        "http://www.dmoz.org/Computers/Programming/Languages/Python/Resources/"
    ]

    def parse(self, response):
        for sel in response.xpath('//ul/li'):
            yield {
                'title': sel.xpath('a/text()').extract(),
                'link': sel.xpath('a/@href').extract(),
                'desc': sel.xpath('text()').extract(),
            }

The version with dicts gives a developer less concepts to learn, and it is easier to explain.

When field metadata is not used and data is exported to JSON/XML yielding Python dicts should be enough. Even when you export to CSV dicts could be enough - columns can be set explicitly by an user.

This should also prevent tickets like https://github.com/scrapy/scrapy/issues/968.

[shaneaevans]

👍 It will make it easier for newcomers and make Scrapy more suitable for small projects. This also means anyting that acts like a dict would be suitable as an item.

@nramirezuy - For well defined projects maybe it would make sense to add a pipeline that requires items to be of a certain type, in addition to any other validation you have.

[eliasdorneles]

+1, will be nice to be able to yield dicts! Less concepts for the newbie user. 😉