前言
系统环境：CentOS7
本文假设你已经安装了virtualenv，并且已经激活虚拟环境ENV1，如果没有，请参考这里：使用virtualenv创建python沙盒（虚拟）环境，在上一篇文章(Scrapy学习笔记(2)-使用pycharm在虚拟环境中运行第一个spider)中我们已经能够使用scrapy的命令行工具创建项目以及spider、使用Pycharm编码并在虚拟环境中运行spider抓取http://quotes.toscrape.com/中的article和author信息, 最后将抓取的信息存入txt文件，上次的spider只能单页爬取，今天我们在上次的spider上再深入一下。
目标
跟踪next（下一页）链接循环爬取http://quotes.toscrape.com/中的article和author信息,将结果保存到mysql数据库中。
正文
1.因为要用Python操作MySQL数据库，所以先得安装相关的Python模块，本文使用MySQLdb
#sudo yum install mysql-devel
#pip install mysql-devel
2.在数据库中创建目标表quotes，建表语句如下：
CREATE TABLE `quotes` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`article` varchar(500) DEFAULT NULL,
`author` varchar(50) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
3.items.py文件详细代码如下：
# -*- coding: utf-8 -*-
# Define here the models for your scraped items
#
# See documentation in:
# http://doc.scrapy.org/en/latest/topics/items.html
import scrapy
class QuotesItem(scrapy.Item):
# define the fields for your item here like:
# name = scrapy.Field()
article=scrapy.Field()
author=scrapy.Field()
pass
4.修改quotes_spider.py如下：
# -*- coding: utf-8 -*-
import scrapy
from ..items import QuotesItem
from urlparse import urljoin
from scrapy.http import Request
class QuotesSpiderSpider(scrapy.Spider):
name = “quotes_spider”
allowed_domains = [“quotes.toscrape.com”]
start_urls = [‘http://quotes.toscrape.com’]
def parse(self, response):
articles=response.xpath(“//div[@class=’quote’]”)
next_page=response.xpath(“//li[@class=’next’]/a/@href”).extract_first()
for article in articles:
item=QuotesItem()
content=article.xpath(“span[@class=’text’]/text()”).extract_first()
author=article.xpath(“span/small[@class=’author’]/text()”).extract_first()
item[‘article’]=content.encode(‘utf-8’)
item[‘author’] = author.encode(‘utf-8’)
yield item#使用yield返回结果但不会中断程序执行
if next_page:#判断是否存在next链接
url=urljoin(self.start_urls[0],next_page)#拼接url
yield Request(url,callback=self.parse)
5.修改pipelines.py文件，将爬取到的数据保存到数据库
# -*- coding: utf-8 -*-
# Define your item pipelines here
#
# Don’t forget to add your pipeline to the ITEM_PIPELINES setting
# See: http://doc.scrapy.org/en/latest/topics/item-pipeline.html
from twisted.enterprise import adbapi
import MySQLdb
import MySQLdb.cursors
class QuotesPipeline(object):
def __init__(self):
db_args=dict(
host=”192.168.0.107″,#数据库主机ip
db=”scrapy”,#数据库名称
user=”root”,#用户名
passwd=”123456″,#密码
charset=’utf8′,#数据库字符编码
cursorclass = MySQLdb.cursors.DictCursor,#以字典的形式返回数据集
use_unicode = True,
)
self.dbpool = adbapi.ConnectionPool(‘MySQLdb’, **db_args)
def process_item(self, item, spider):
self.dbpool.runInteraction(self.insert_into_quotes, item)
return item
def insert_into_quotes(self,conn,item):
conn.execute(
”’
INSERT INTO quotes(article,author)
VALUES(%s,%s)
”’
,(item[‘article’],item[‘author’])
)
6.pipeline.py文件代码不变：
# -*- coding: utf-8 -*-
# Scrapy settings for quotes project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
# http://doc.scrapy.org/en/latest/topics/settings.html
# http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
# http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html
BOT_NAME = ‘quotes’
SPIDER_MODULES = [‘quotes.spiders’]
NEWSPIDER_MODULE = ‘quotes.spiders’
# Obey robots.txt rules
ROBOTSTXT_OBEY = True
# Configure item pipelines
# See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html
ITEM_PIPELINES = {
‘quotes.pipelines.QuotesPipeline’: 300,
}
7.开始运行spider
(ENV1) [eason@localhost quotes]$ scrapy crawl quotes_spider
8.检验结果，Done!
