scrapy爬虫之SyntaxError: can't assign to literal

问题描述：

当执行scrapy crawl tutu时，报出如下错误：

[root@Uu tutu]# scrapy crawl tutu
Traceback (most recent call last):
  File "/usr/bin/scrapy", line 11, in 
    sys.exit(execute())
  File "/usr/lib64/python2.7/site-packages/scrapy/cmdline.py", line 149, in execute
    cmd.crawler_process = CrawlerProcess(settings)
  File "/usr/lib64/python2.7/site-packages/scrapy/crawler.py", line 249, in __init__
    super(CrawlerProcess, self).__init__(settings)
  File "/usr/lib64/python2.7/site-packages/scrapy/crawler.py", line 137, in __init__
    self.spider_loader = _get_spider_loader(settings)
  File "/usr/lib64/python2.7/site-packages/scrapy/crawler.py", line 336, in _get_spider_loader
    return loader_cls.from_settings(settings.frozencopy())
  File "/usr/lib64/python2.7/site-packages/scrapy/spiderloader.py", line 61, in from_settings
    return cls(settings)
  File "/usr/lib64/python2.7/site-packages/scrapy/spiderloader.py", line 25, in __init__
    self._load_all_spiders()
  File "/usr/lib64/python2.7/site-packages/scrapy/spiderloader.py", line 47, in _load_all_spiders
    for module in walk_modules(name):
  File "/usr/lib64/python2.7/site-packages/scrapy/utils/misc.py", line 71, in walk_modules
    submod = import_module(fullpath)
  File "/usr/lib64/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/home/BS/scrapy/tutu/tutu/spiders/tutu_spider.py", line 12
    imgurls = ['imgurl'] = response.css('.post img::attr(src)').extract()
SyntaxError: can't assign to literal

可知，这是一个语法错误：不能指定到文字。

经分析，问题解决如下：

问题解决：

 

[root@Uu tutu]# cd tutu/spiders/
[root@Uu spiders]# vi tutu_spider.py 
import scrapy
from tutu.items import TutuItem

class TutuSpider(scrapy.Spider):
        name = 'tutu'
        allowed_domains = ['lab.scrapyd.cn']
        start_urls = [
                'http://lab.scrapyd.cn/archives/55.html'
        ]
        def parse(self , response):
                item = TutuItem()
                imgurls = response.css(".post img::attr(src)").extr
act()
                item['imgurl'] = imgurls
                yield item
~
~
~
~
~
"tutu_spider.py" 14L, 345C written

 分析得知，是css语句的问题，即，css的括号中要用双引号，不能用单引号。

即，将css语句中括号内的单引号换成双引号即可。