Python下使用Scrapy爬取网页内容的实例
上周用了一周的时间学习了Python和Scrapy，实现了从0到1完整的网页爬虫实现。研究的时候很痛苦，但是很享受，做技术的嘛。
首先，安装Python，坑太多了，一个个爬。由于我是windows环境，没钱买mac,在安装的时候遇到各种各样的问题，确实各种各样的依赖。
安装教程不再赘述。如果在安装的过程中遇到ERROR：需要windowsc/c++问题，一般是由于缺少windows开发编译环境，晚上大多数教程是安装一个VisualStudio，太不靠谱了，事实上只要安装一个WindowsSDK就可以了。
下面贴上我的爬虫代码：
爬虫主程序：
#-*-coding:utf-8-*-
importscrapy
fromscrapy.httpimportRequest
fromzjf.FsmzItemsimportFsmzItem
fromscrapy.selectorimportSelector
#圈圈：情感生活
classMySpider(scrapy.Spider):
#爬虫名
name="MySpider"
#设定域名
allowed_domains=["nvsheng.com"]
#爬取地址
start_urls=[]
#flag
x=0
#爬取方法
defparse(self,response):
item=FsmzItem()
sel=Selector(response)
item['title']=sel.xpath('//h1/text()').extract()
item['text']=sel.xpath('//*[@class="content"]/p/text()').extract()
item['imags']=sel.xpath('//div[@id="content"]/p/a/img/@src|//div[@id="content"]/p/img/@src').extract()
ifMySpider.x==0:
page_list=MySpider.getUrl(self,response)
forpage_singleinpage_list:
yieldRequest(page_single)
MySpider.x+=1
yielditem
#init:动态传入参数
#命令行传参写法：scrapycrawlMySpider-astart_url="http://some_url"
def__init__(self,*args,**kwargs):
super(MySpider,self).__init__(*args,**kwargs)
self.start_urls=[kwargs.get('start_url')]
defgetUrl(self,response):
url_list=[]
select=Selector(response)
page_list_tmp=select.xpath('//div[@class="viewnewpages"]/a[not(@class="next")]/@href').extract()
forpage_tmpinpage_list_tmp:
ifpage_tmpnotinurl_list:
url_list.append("http://www.nvsheng.com/emotion/px/"+page_tmp)
returnurl_list
PipeLines类
#-*-coding:utf-8-*-
#Defineyouritempipelineshere
#
#Don'tforgettoaddyourpipelinetotheITEM_PIPELINESsetting
#See:http://doc.scrapy.org/en/latest/topics/item-pipeline.html
fromzjfimportsettings
importjson,os,re,random
importurllib.request
importrequests,json
fromrequests_toolbelt.multipart.encoderimportMultipartEncoder
classMyPipeline(object):
flag=1
post_title=''
post_text=[]
post_text_imageUrl_list=[]
cs=[]
user_id=''
def__init__(self):
MyPipeline.user_id=MyPipeline.getRandomUser('37619,18441390,18441391')
#processthedata
defprocess_item(self,item,spider):
#获取随机user_id，模拟发帖
user_id=MyPipeline.user_id
#获取正文text_str_tmp
text=item['text']
text_str_tmp=""
forstrintext:
text_str_tmp=text_str_tmp+str
#print(text_str_tmp)
#获取标题
ifMyPipeline.flag==1:
title=item['title']
MyPipeline.post_title=MyPipeline.post_title+title[0]
#保存并上传图片
text_insert_pic=''
text_insert_pic_w=''
text_insert_pic_h=''
forimag_urlinitem['imags']:
img_name=imag_url.replace('/','').replace('.','').replace('|','').replace(':','')
pic_dir=settings.IMAGES_STORE+'%s.jpg'%(img_name)
urllib.request.urlretrieve(imag_url,pic_dir)
#图片上传，返回json
upload_img_result=MyPipeline.uploadImage(pic_dir,'image/jpeg')
#获取json中保存图片路径
text_insert_pic=upload_img_result['result']['image_url']
text_insert_pic_w=upload_img_result['result']['w']
text_insert_pic_h=upload_img_result['result']['h']
#拼接json
ifMyPipeline.flag==1:
cs_json={"c":text_str_tmp,"i":"","w":text_insert_pic_w,"h":text_insert_pic_h}
else:
cs_json={"c":text_str_tmp,"i":text_insert_pic,"w":text_insert_pic_w,"h":text_insert_pic_h}
MyPipeline.cs.append(cs_json)
MyPipeline.flag+=1
returnitem
#spider开启时被调用
defopen_spider(self,spider):
pass
#sipder关闭时被调用
defclose_spider(self,spider):
strcs=json.dumps(MyPipeline.cs)
jsonData={"apisign":"99ea3eda4b45549162c4a741d58baa60","user_id":MyPipeline.user_id,"gid":30,"t":MyPipeline.post_title,"cs":strcs}
MyPipeline.uploadPost(jsonData)
#上传图片
defuploadImage(img_path,content_type):
"uploadImagefunctions"
#UPLOAD_IMG_URL="http://api.qa.douguo.net/robot/uploadpostimage"
UPLOAD_IMG_URL="http://api.douguo.net/robot/uploadpostimage"
#传图片
#imgPath='D:\pics\http___img_nvsheng_com_uploads_allimg_170119_18-1f1191g440_jpg.jpg'
m=MultipartEncoder(
#fields={'user_id':'192323',
#'images':('filename',open(imgPath,'rb'),'image/JPEG')}
fields={'user_id':MyPipeline.user_id,
'apisign':'99ea3eda4b45549162c4a741d58baa60',
'image':('filename',open(img_path,'rb'),'image/jpeg')}
)
r=requests.post(UPLOAD_IMG_URL,data=m,headers={'Content-Type':m.content_type})
returnr.json()
defuploadPost(jsonData):
CREATE_POST_URL=http://api.douguo.net/robot/uploadimagespost
reqPost=requests.post(CREATE_POST_URL,data=jsonData)
defgetRandomUser(userStr):
user_list=[]
user_chooesd=''
foruser_idinstr(userStr).split(','):
user_list.append(user_id)
userId_idx=random.randint(1,len(user_list))
user_chooesd=user_list[userId_idx-1]
returnuser_chooesd
字段保存Items类
#-*-coding:utf-8-*- #Defineherethemodelsforyourscrapeditems # #Seedocumentationin: #http://doc.scrapy.org/en/latest/topics/items.html importscrapy classFsmzItem(scrapy.Item): #definethefieldsforyouritemherelike: #name=scrapy.Field() title=scrapy.Field() #tutor=scrapy.Field() #strongText=scrapy.Field() text=scrapy.Field() imags=scrapy.Field()
在命令行里键入
scrapycrawlMySpider-astart_url=www.aaa.com
这样就可以爬取aaa.com下的内容了
以上这篇Python下使用Scrapy爬取网页内容的实例就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持毛票票。