python - module._init_() 最多接受 2 个参数(给定 3 个)(scrapy 教程 w/xpath)

Question

我不确定这里怎么有 3 个争论，如果是这样，我如何从 items.py 调用 DmozItem？这似乎是我缺少的一个简单的继承问题。此代码是直接从scrapy教程网站复制的。

-- 外壳错误 --

SyntaxError: invalid syntax
PS C:\Users\Steve\tutorial> scrapy crawl dmoz
Traceback (most recent call last):
  File "c:\python27\scripts\scrapy-script.py", line 9, in <module>
load_entry_point('scrapy==1.0.3', 'console_scripts', 'scrapy')()
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\cmdline.py", line 142, in execute
cmd.crawler_process = CrawlerProcess(settings)
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\crawler.py", line 209, in __init__
super(CrawlerProcess, self).__init__(settings)
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\crawler.py", line 115, in __init__
self.spider_loader = _get_spider_loader(settings)
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\crawler.py", line 296, in _get_spider_loader
return loader_cls.from_settings(settings.frozencopy())
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\spiderloader.py", line 30, in from_settings
return cls(settings)
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\spiderloader.py", line 21, in __init__
for module in walk_modules(name):
  File "C:\Python27\lib\site-packages\scrapy-1.0.3-py2.7.egg\scrapy\utils\misc.py", line 71, in walk_modules
submod = import_module(fullpath)
  File "C:\Python27\lib\importlib\__init__.py", line 37, in import_module
__import__(name)
  File "C:\Users\Steve\tutorial\tutorial\spiders\dmoz_spider.py", line 3, in <module>
from tutorial.items import DmozItem
  File "C:\Users\Steve\tutorial\tutorial\items.py", line 11, in <module>
class DmozItem(scrapy.item):
TypeError: Error when calling the metaclass bases
module._init_() takes at most 2 arguments (3 given)

-- items.py -- 我的用于解析的项目列表

import scrapy


class DmozItem(scrapy.item):

title = scrapy.Field()
link = scrapy.Field()
desc = scrapy.Field()

-- dmoz_spider.py -- 这是蜘蛛

import scrapy

from tutorial.items import DmozItem

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

Answer 1

您输入了错误的 scrapy.Item 类名。

在items.py中，更改:

scrapy.item

至

scrapy.Item

它应该看起来像这样:

import scrapy

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