selenium的使用与scrapy的简介

selenium的使用与scrapy的简介

  • Xpath的使用

doc = '''
<html>
 <head>
  <base href='http://example.com/' />
  <title>Example website</title>
 </head>
 <body>
  <div id='images'>
   <a href='image1.html' id='id_a'>Name: My image 1 <br/><img src='image1_thumb.jpg' /></a>
   <a href='image2.html'>Name: My image 2 <br /><img src='image2_thumb.jpg' /></a>
   <a href='image3.html'>Name: My image 3 <br /><img src='image3_thumb.jpg' /></a>
   <a href='image4.html'>Name: My image 4 <br /><img src='image4_thumb.jpg' /></a>
   <a href='image5.html' class='li li-item' name='items'>Name: My image 5 <br /><img src='image5_thumb.jpg' /></a>
   <a href='image6.html' name='items'><span><h5>test</h5></span>Name: My image 6 <br /><img src='image6_thumb.jpg' /></a>
  </div>
 </body>
</html>
'''

from lxml import etree

html = etree.HTML(doc)
html=etree.parse('search.html',etree.HTMLParser())
1.获取所有节点
a = html.xpath('//*')  # 根目录下所有节点获取

2.获取指定结果(结果为列表)
a=html.xpath('//head')    # [<Element head at 0x1f7813be880>]

3.子节点,子孙节点
a = html.xpath('//div/a')
a = html.xpath('//body/a')  # 查找不到body子路径有a那么就会直接返回一个空列表
a = html.xpath('//body//a')

4.父节点
a = html.xpath('//body//a[@href="image1.html"]/..')
a = html.xpath('//body//a[1]/..')
####################
a= html.xpath('//body//a[1]/parent::*')
a = html.xpath('//body//a[1]/parent::div')

5.属性匹配
a = html.xpath('body//a[@href="image1.html"]')

6.文本获取 text()
a = html.xpath('//body//a[@href="image1.html"]/text()')

7.属性获取
a = html.xpath('//body//a/@href')  # 获取所有属性
a = html.xpath('//body//a/@id')
注意从1开始取(不是从0)
a = html.xpath('//body//a[1]/@id')

8.属性多值匹配
a标签有多个class类,直接匹配就不可以了,需要用contains
a = html.xpath('//body//a[@class="li"]')
a = html.xpath('//body//a[@name="items"]')
a = html.xpath('//body//a[contains(@class,"li")]')
a = html.xpath('//body//a[contains(@class,"li")]/text()')

9.多属性匹配
a = html.xpath('//body//a[contains(@class,"li") or @name="items"]')
a = html.xpath('//body//a[contains(@class,"li") and @name="items"]/text')

10.顺序查找
a = html.xpath('//a[2]/text()')
a = html.xpath('//a[3]/@href')
取最后一个
a = html.xpath('//a[last()]/@href')
位置小于3的
a = html.xpath('//a[position()<3]/@href')
倒数第二个
a = html.xpath('//a[last()-2]/@href')

11.节点轴选择
ancestor  # 祖先节点
 使用了*获取所有祖先节点
a = html.xpath('//a/ancestor::*')
获取祖先节点中的div
a = html.xpath('//a/ancestor::div')
attribute 属性值
a = html.xpath('//a[1]/attribute::*')
a = html.xpath('//a[1]/attribute::href')
child  # 直接子节点
a = html.xpath('//a[1]/child::*')
descendant  所有子孙节点
a = html.xpath('//a[6]/descendant::*')

following  当前节点之后所有节点
a = html.xpath('//a[1]/following::*')
a = html.xpath('//a[1]/following::*[1]/@href')
following-sibling  当前节点之后同级别节点
a = html.xpath('//a[1]/following-sibling::*')
a =html.xpath('//a[1]/following-sibling::a')
a =html.xpath('//a[1]/following-sibling::*[2]')
a =html.xpath('//a[1]/following-sibling::*[2]/@href')

print(a)
  • selenium动作链
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver import ActionChains
import time

bro = webdriver.Chrome(executable_path='./chromedriver.exe')
bro.get('http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable')
bro.implicitly_wait(10)

try:
    bro.switch_to.frame('iframeResult')
    sourse = bro.find_element(by=By.ID, value='draggable')
    target = bro.find_element(by=By.ID, value='droppable')
    # 方式一:基于同一个动作链串行执行
    # actions = ActionChains(bro)  # 拿到动作链串行对象
    # actions.drag_and_drop(sourse,target)  # 将动作放到动作链中串行执行
    # actions.perform()

    # 方式二:不同的动作链,每次移动的位移都不同
    ActionChains(bro).click_and_hold(sourse).perform()
    distance = target.location['x'] - sourse.location['x']
    print('目标距离源的轴距离:', distance)
    trace = 0
    while trace < distance:
        ActionChains(bro).move_by_offset(xoffset=4, yoffset=0).perform()
        trace += 4
    ActionChains(bro).release().perform()
    time.sleep(10)
except Exception as e:
    print(e)
finally:
    bro.close()
  • 自动登录某网站
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver import ActionChains
import time
from selenium.webdriver.chrome.options import Options

options = Options()
options.add_argument("--disable-blink-features=AutomationControlled")  # 去掉自动化控制的提示
bro = webdriver.Chrome(executable_path='./chromedriver.exe',options=options)
bro.get('https://kyfw.12306.cn/otn/resources/login.html')

bro.implicitly_wait(10)
try:
    username = bro.find_element(by=By.ID,value='J-userName')
    username.send_keys('')
    password = bro.find_element(by=By.ID,value='J-password')
    password.send_keys('')
    time.sleep(3)
    btn = bro.find_element(by=By.ID,value='J-login')
    btn.click()
    span = bro.find_element(by=By.ID,value='nc_1_n1z')
    ActionChains(bro).click_and_hold(span).perform()
    ActionChains(bro).move_by_offset(xoffset=300,yoffset=0).perform()
    time.sleep(5)
except Exception as e:
    print(e)

finally:
    bro.close()
  • 打码平台的使用

打码平台其实就是我们将验证码图片发往第三方,然后第三方帮我们解决,我们只需要用钱就可以了,简单的验证码花钱少一些,复杂的验证码花钱较多例如steam的就需要很多钱
  • 打码平台自动登录

import time

from selenium import webdriver
from selenium.webdriver.common.by import By
from chaojiying import Chaojiying_Client
from PIL import Image
bro = webdriver.Chrome(executable_path='./chromedriver.exe')
bro.get('http://www.chaojiying.com/user/login/')
bro.implicitly_wait(10)
bro.maximize_window()
try:
    username = bro.find_element(by=By.XPATH,value='/html/body/div[3]/div/div[3]/div[1]/form/p[1]/input')
    password = bro.find_element(by=By.XPATH,value='/html/body/div[3]/div/div[3]/div[1]/form/p[2]/input')
    code = bro.find_element(by=By.XPATH, value='/html/body/div[3]/div/div[3]/div[1]/form/p[3]/input')
    btn = bro.find_element(by=By.XPATH, value='/html/body/div[3]/div/div[3]/div[1]/form/p[4]/input')
    username.send_keys('306334678')
    password.send_keys('lqz123')
    bro.save_screenshot('main.png')
    img = bro.find_element(By.XPATH,'/html/body/div[3]/div/div[3]/div[1]/form/div/img')
    location = img.location
    size = img.size
    print(location)
    print(size)
    img_tu = (int(location['x']), int(location['y']), int(location['x'] + size['width']), int(location['y'] + size['height']))
    img = Image.open('./main.png')
    fram = img.crop(img_tu)
    fram.save('code.png')
    chaojiying = Chaojiying_Client('','','')
    im = open('code.png','rb').read()
    print(chaojiying.PostPic(im,1902))
    res_code = chaojiying.PostPic(im,1902)['pic_str']
    code.send_keys(res_code)
    time.sleep(5)
    btn.click()
    time.sleep(5)
except Exception as e:
    print(e)

finally:
    bro.close()
  • 爬取某东商品
from selenium import webdriver
from selenium.webdriver.common.by import By
import time
from selenium.webdriver.common.keys import Keys


def get_goods(driver):
    try:
        goods = driver.find_elements(by=By.CLASS_NAME, value='gl-item')
        for good in goods:
            name = good.find_element(by=By.CSS_SELECTOR, value='.p-name em').text
            price = good.find_element(by=By.CSS_SELECTOR, value='.p-price i').text
            commit = good.find_element(by=By.CSS_SELECTOR, value='.p-commit a').text
            url = good.find_element(by=By.CSS_SELECTOR, value='.p-name a').get_attribute('href')
            img = good.find_element(by=By.CSS_SELECTOR, value='.p-img img').get_attribute('src')
            if not img:
                img = 'https://' + good.find_element(by=By.CSS_SELECTOR, value='.p-img img').get_attribute(
                    'data-lazy-img')
                print('''
                            商品名字:%s
                            商品价格:%s
                            商品链接:%s
                            商品图片:%s
                            商品评论:%s
                            ''' % (name, price, url, img, commit))
        button = driver.find_elements(by=By.PARTIAL_LINK_TEXT,value='下一页')
        button.click()
        time.sleep(1)
        get_goods(driver)
    except Exception as e:
        print(e)


def spider(url,keyword):
    driver = webdriver.Chrome(executable_path='./chromedriver.exe')
    driver.get(url)
    driver.implicitly_wait(10)
    try:
        input_tag = driver.find_element(by=By.ID,value='key')
        input_tag.send_keys(keyword)
        input_tag.send_keys(Keys.ENTER)
        get_goods(driver)
    finally:
        driver.close()


if __name__ == '__main__':
    spider('https://www.jd.com/',keyword='精品内衣')

  • scrapy介绍

# 前面学的都是模块,做专业的爬虫,可以使用框架 (django:web)  scrapy:爬虫框架
	-做爬虫用的东西,都封装好了,只需要在固定的位置写固定的代码即可
    
# scrapy 号称爬虫界的djagno
	-django 大而全,做web相关的它都用
    -scrapy 大而全,做爬虫的,它都用
    
    
# 介绍
Scrapy一个开源和协作的框架,其最初是为了页面抓取 (更确切来说, 网络抓取 )所设计的,使用它可以以快速、简单、可扩展的方式从网站中提取所需的数据。但目前Scrapy的用途十分广泛,可用于如数据挖掘、监测和自动化测试等领域,也可以应用在获取API所返回的数据或者通用的网络爬虫



# 安装 scrapy
	-mac,linux:
    	pip3 install scrapy
    -win:看人品
    	-pip3 install scrapy
    	-人品不好:
        1、pip3 install wheel #安装后,便支持通过wheel文件安装软件   xx.whl
        3、pip3 install lxml
        4、pip3 install pyopenssl
        5、下载并安装pywin32:https://sourceforge.net/projects/pywin32/files/pywin32/
        6、下载twisted的wheel文件:http://www.lfd.uci.edu/~gohlke/pythonlibs/#twisted
        7、执行pip3 install 下载目录\Twisted-17.9.0-cp36-cp36m-win_amd64.whl
        8、pip3 install scrapy
        
        
 # 释放出scrapy 可执行文件
	-以后使用这个创建爬虫项目 ---》django-admin创建django项目
    
    
 # 创建爬虫项目
	scrapy startproject myfirstscrapy
    
 # 创建爬虫 [django创建app]
	scrapy genspider cnblogs www.cnblogs.com
    
 # 启动爬虫 
	scrapy crawl cnblogs --nolog
    
 # pycharm中运行
    新建run.py
    from scrapy.cmdline import execute
    execute(['scrapy', 'crawl', 'cnblogs','--nolog'])
posted @ 2022-12-06 22:10  Joseph-bright  阅读(54)  评论(0编辑  收藏  举报