python 爬虫相关含Scrapy框架

1、从酷狗网站爬取 新歌首发的新歌名字、播放时长、链接等

from bs4 import BeautifulSoup as BS
import requests
import re
import json
class StockCrawler():
    
    def __init__(self):
        pass
    
    def get_stockinfo(self,url):
        res=requests.get(url)
        res.encoding='utf-8'
        soup=BS(res.text,'html.parser')
        
        stock_info=[]
        div=soup.find_all('div',id='SongtabContent')  #定位最外层的新歌区域标签
        li=div[0].find_all('li')
        
        for i in li:  #遍历每首歌的标签，分别取歌名、歌播放时长、链接
            print(i)
            
            link='http:'+i.find_all('a')[0]['href']
            print('link:',link)
            
            songname=i.a.find_all('span',class_='songName')[0].text
            songtime=i.a.find_all('span',class_='songTime')[0].text
            print('songname:',songname)
            print('songtime:',songtime)
            
            stock_info.append((songname,songtime,link))
            
        return stock_info

    def write_file(self,data,file_name):
        with open(file_name,'w',encoding='utf-8') as fp:
            for i in data:
                fp.write(i[0]+','+i[1]+','+i[2]+'
')   #写入文件

if __name__=='__main__':
    
    url='http://www.kugou.com/'
    stockcrawler=StockCrawler()
    data=stockcrawler.get_stockinfo(url)
    stockcrawler.write_file(data,'f:\test\pppp.txt')

2、sohu网站首页 爬取包含"体育"2个字的链接

r = requests.get("http://www.sohu.com")
r.encoding="utf-8"
html  = r.text
soup = BeautifulSoup(html,"html.parser")#html可以是html内容

links = []
for i in list(soup.find_all(["a"])):
    try:
        print(i["href"])
        if i["href"].strip().startswith(r"//"):
            print(1)
            i["href"]="http:"+i["href"]
        if i["href"].find("javascript")>=0:
            print(2)
            continue
        if i["href"].find("mailto")>=0:
            print(3)
            continue
        if len(i["href"].strip())==1:
            print(4)
            continue
        #print(i["href"])
        links.append(i["href"].strip())
        #print("*"*50)
    except Exception as e:
        print(e)

for link in links:
    print(link)

x=1
for link in links:
    r = requests.get(link)
    r.encoding = "utf-8"
    if "体育" in r.text:
        with open("e:\pic\"+str(x)+".txt","w",encoding="utf-8") as fp:
            fp.write(r.text)
            x+=1

3、使用代理服务器 发送请求

proxy='168.0.86.146:8080'

#如果代理需要验证，只需要在前面加上用户名密码，如下所示

# proxy='username:password@124.243.226.18:8888'
proxies={
    'http':'http://'+proxy,
    'https':'https://'+proxy,
}
try:
    response=requests.get('http://httpbin.org/get',proxies=proxies)
    print(response.text)
except requests.exceptions.ConnectionError as e:
    print("Error",e.args)

4、Srapy 爬虫框架

#Scrapy 爬虫框架
'''
scrapy startproject testman

1）items.py 存储你要爬取的数据的变量。
类似于字典。

2）pipelines.py（保存爬取后的数据）:保存你抓取网页，分析后的存储的
变量中的数据存入到某个地方。（json文件）txt文件、excel 、数据库。

3）settings.py：设定spider的优先级，自动生成的，取消掉数据就可以了。
ITEM_PIPELINES = {'gr.pipelines.GrPipeline': 300,}

gr：抓取器的名字

4）在spider的目录下，写一下分析逻辑（从网页中取想要的数据，保存到items.py声明的变量中。）


框架使用的步骤：
1 新建scrapy工程，在任意目录下，cmd中执行：scrapy startproject groad
2 生成工程的内容，在scrapy的根目录下cmd中
执行：scrapy genspider newsong www.kugou.com
3 编写相关代码
4 在scrapy的根目录下，cmd执行抓取：scrapy crawl newsong


'''

5、Scrapy框架的例子，酷狗爬取新歌首发的歌曲名称、播放时长、歌曲链接等

#items.py文件内容
import scrapy

class GroadItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    #定义项目的字段
    songname=scrapy.Field() #歌曲名称
    songtime=scrapy.Field()#歌曲播放时间
    href_song=scrapy.Field()#歌曲播放链接


if __name__=='__main__':
    g=GroadItem()
    print(g['songname'])


#pipelines.py 文件内容


import json
class GroadPipeline(object):
    def __init__(self):
        
        self.filename=open('f:\test\newsong.txt','w',encoding='utf-8')

    def process_item(self, item, spider):
        text=json.dumps(dict(item),ensure_ascii=False)+'
'
        self.filename.write(text)
        return item
    
    def close_spider(self,spider):
        self.filename.close()


#settings.py文件，放开注释

ITEM_PIPELINES = {
    'groad.pipelines.GroadPipeline': 300,
}


#newsong.py 文件


import scrapy
from groad.items import GroadItem

class NewsongSpider(scrapy.Spider):
    name = 'newsong'
    allowed_domains = ['www.kugou.com']
    start_urls = ['http://www.kugou.com/']

    def parse(self, response):
        item=GroadItem()
        for i in range(1,len(response.xpath('//*[@id="SongtabContent"]/ul'))+1):
            for j in range(1,len(response.xpath('//*[@id="SongtabContent"]/ul[%s]/li' % i))+1):
                item['songname']=response.xpath('//*[@id="SongtabContent"]/ul[%s]/li[%s]/a/span[1]/text()' % (i,j)).extract()[0]
                item['songtime'] =response.xpath('//*[@id="SongtabContent"]/ul[%s]/li[%s]/a/span[@class="songTime"]/text()' % (i, j)).extract()[0]
                item['href_song'] = response.xpath('//*[@id="SongtabContent"]/ul[%s]/li[%s]/a/@href' % (i, j)).extract()[0]

                yield item