scrapy爬虫 简单入门

1. 使用cmd+R命令进入命令行窗口，并进入你需要创建项目的目录

cd 项目地址

2. 创建项目

scrapy startproject <项目名>
cd <项目名>

例如

scrapy startproject quote
cd quote

3. 编写item.py文件（定义需要爬取的文件）

import scrapy
class QuoteItem(scrapy.Item):
    # define the fields for your item here like:
    text = scrapy.Field()
    author = scrapy.Field()
    tags = scrapy.Field()

4. 创建爬虫文件

scrapy genspider <爬虫文件名> <域名>

例如

scrapy genspider myspider quotes.toscrape.com

5. 编写myspider.py文件

import scrapy
from quote.items import QuoteItem

class MyspiderSpider(scrapy.Spider):
    name = 'myspider'
    allowed_domains = ['quotes.toscrape.com']
    start_urls = ['http://quotes.toscrape.com/']

    def parse(self, response):
        for each in response.xpath('//div[@class="quote"]'):
            item = QuoteItem()
            item['text'] = each.xpath('./span/text()').extract()[0]
            item['author'] = each.xpath('.//small/text()').extract()[0]
            list = each.xpath('.//a[@class="tag"]/text()').extract()
            #列表形式的文件不能存入mysql,需要弄成str形式
            item['tags']= '/'.join(list)
            yield item

        next = response.xpath('//li[@class="next"]/a/@href').extract()[0]
        url = response.urljoin(next)
        yield scrapy.Request(url=url,callback=self.parse)

6. 编写pipelines.py（如果需要存入到数据库）

import pymysql.cursors

class QuotePipeline(object):
    def __init__(self):
        self.connect = pymysql.connect(
            host='localhost',
            user='root',
            password='',
            database='quotes',
            charset='utf8',
        )
        self.cursor = self.connect.cursor()

    def process_item(self, item, spider):
        item = dict(item)
        sql = 'insert into quote(text,author,tags) values(%s,%s,%s)'
        self.cursor.execute(sql,(item['text'],item['author'],item['tags']))
        self.connect.commit()
        return item

    def close_spider(self,spider):
        self.cursor.close()
        self.connect.close()　

7. 修改setting.py文件

ROBOTSTXT_OBEY = True

8. 运行

scrapy crawl myspider

9. 保存为csv文件

scrapy crawl quotes –o quotes.csv

参考资料

https://www.cnblogs.com/shuimohei/p/10491833.html

https://blog.csdn.net/ck784101777/article/details/104468780/