机械网站精选网站开发的技术风险

创建crawlspider爬虫文件：

scrapy genspider -t crawl 爬虫文件名 爬取的域名scrapy genspider -t crawl read https://www.dushu.com/book/1206.html

LinkExtractor 链接提取器通过它，Spider可以知道从爬取的页面中提取出哪些链接，提取出的链接会自动生成Request请求对象

class ReadSpider(CrawlSpider):name = "read"allowed_domains = ["www.dushu.com"]start_urls = ["https://www.dushu.com/book/1206_1.html"]# LinkExtractor 链接提取器通过它，Spider可以知道从爬取的页面中提取出哪些链接。提取出的链接会自动生成Request请求对象rules = (Rule(LinkExtractor(allow=r"/book/1206_\d+\.html"), callback="parse_item", follow=False),)def parse_item(self, response):name_list = response.xpath('//div[@class="book-info"]//img/@alt')src_list = response.xpath('//div[@class="book-info"]//img/@data-original')for i in range(len(name_list)):name = name_list[i].extract()src = src_list[i].extract()book = ScarpyReadbook41Item(name=name, src=src)yield book

开启管道、
写入文件

class ScarpyReadbook41Pipeline:def open_spider(self, spider):self.fp = open('books.json', 'w', encoding='utf-8')def process_item(self, item, spider):self.fp.write(str(item))return itemdef close_spider(self, spider):self.fp.close()

运行之后发现没有第一页数据
需要在start_urls里加上_1，不然不会读取第一页数据

start_urls = ["https://www.dushu.com/book/1206_1.html"]