爬虫学习之1：初试scrapy:爬取应届生求职网招聘信息
之前用BeautifulSoup写过爬虫，这段时间工作需要发布一些就业信息，尝试下Scrapy框架，花了一个网上稍微了解了一下，对Scrapy框架有了一定了解，已经可以爬取到数据，并保存为Json、CSV格式，并顺利写入MySQL，但很多细节还需要进一步了解，使用框架确实省事。下面直接贴过程：
一、安装Scrapy
本来在Linux比较方便，但我电脑里的Ubuntu由于搭建了很多Hadoop相关的东西，不想搞得很混乱，就在Win7下搭建吧，我已经装了Python3.6版本的Anaconda，所以直接在命令行：pip install scrapy，安装了很多依赖包，最后提示缺少Microsoft Visual C++2015，网上下载安装后还是提示twisted安装失败，懒得想了，直接到网上下twisted.whl，然后pip安装一下，scrapy安装成功。
二、爬取应届生求职网数据代码编写
这里主要参考的是scrapy官方文档：http://scrapy-chs.readthedocs.io/zh_CN/latest/intro/overview.html，也参考了很多博客文章。
1.创建项目：
cmd > scrapy startproject jobYJS
cmd > cd ./jobYJS
cmd > scrapy genspider yinjiesheng_spider s.yingjiesheng.com生成的源代码目录如下：
2.items.py代码编写
# -*- coding: utf-8 -*-
import scrapy
class JobyjsItem(scrapy.Item):
# define the fields for your item here like:
# name = scrapy.Field()
title = scrapy.Field()
companyUrl = scrapy.Field()
pubDate = scrapy.Field()
3.yinjiesheng_spider.py代码编写
# -*- coding: utf-8 -*-
import scrapy
from jobYJS.items import JobyjsItem
class YinjieshengSpiderSpider(scrapy.Spider):
name = 'yinjiesheng_spider'
allowed_domains = ['s.yingjiesheng.com']
base_url = 'http://s.yingjiesheng.com/search.php?word=计算机&area=2124&sort=score&start='
pageToCrawl=10
offset = 0
start_urls = [base_url+str(offset)]
def parse(self, response):
li_list = response.xpath("//ul[contains(@class,'searchResult')]/li")
for li in li_list:
item = JobyjsItem()
item['title']=li.xpath("./div/h3[contains(@class,'title')]/a/text()").extract()[0]
item['companyUrl']=li.xpath("./div/h3[contains(@class,'title')]/a/@href").extract()[0]
item['pubDate']=li.xpath("./div/p/span[contains(@class,'r date')]/text()").extract()
yield item
if self.offset <= self.pageToCrawl*10:
self.offset += 10
url = self.base_url + str(self.offset)
yield scrapy.Request(url, callback=self.parse)
4.结果保存为json格式的pipelines.py代码:
# -*- coding: utf-8 -*-
import json
import time
class JobyjsPipeline(object):
def __init__(self):
today =time.strftime('%Y-%m-%d',time.localtime(time.time()))
self.f = open('yinjiesheng_job'+today+'.json','a+')
def process_item(self, item, spider):
content = json.dumps(dict(item),ensure_ascii=False)
self.f.write(content)
return item
def close_spider(self,spider):
self.f.close()5.结果保存为CSV格式的pipeline2CSV.py
import csv
import time
import itertools
import codecs
class JobyjsPipeline(object):
def process_item(self, item, spider):
today =time.strftime('%Y-%m-%d',time.localtime(time.time()))
filename = today+'.csv'
with open(filename,'a+') as csvfile:
writer=csv.writer(csvfile)
writer.writerow((item['title'],item['companyUrl'],item['pubDate']))
return item6.结果存储到MySQL的pipelines2MySQL,py
import pymysql
def dbHandle():
conn = pymysql.connect(
host = "localhost",
user = "root",
passwd = "123456",
charset = "utf8",
use_unicode = False
)
return conn
class JobyjsPipeline(object):
def process_item(self,item,spider):
dbObject = dbHandle()
cursor = dbObject.cursor()
cursor.execute("USE crawl")
sql = "INSERT INTO yinjiesheng(title,companyUrl,pubDate) VALUES(%s,%s,%s)"
try:
cursor.execute(sql,(item['title'],item['companyUrl'],item['pubDate']))
cursor.connection.commit()
except BaseException as e:
print("错误在这里>>>>>>>>>>>>>",e,"<<<<<<<<<<<<<错误在这里")
dbObject.rollback()
return item
7.Setting.py代码
BOT_NAME = 'jobYJS'
SPIDER_MODULES = ['jobYJS.spiders']
NEWSPIDER_MODULE = 'jobYJS.spiders'
ITEM_PIPELINES = {
'jobYJS.pipelines.JobyjsPipeline': 300,
'jobYJS.pipeline2CSV.JobyjsPipeline':400,
'jobYJS.pipelines2MySQL.JobyjsPipeline':500,
}三、测试运行
事先在MySQL中建立了crawl database，并在其中新建了yinjiesheng表，其中包含三个字段
cmd> scrapy crawl yinjiesheng_spider