Python使用Selenium爬取淘宝异步加载的数据

淘宝的页面很复杂，如果使用分析ajax或者js的方式，很麻烦

抓取淘宝‘美食’上面的所有食品信息

spider.py

#encoding:utf8
import re

from selenium import webdriver
from selenium.common.exceptions import TimeoutException

from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

from bs4 import BeautifulSoup
from config import *
import pymongo

client=pymongo.MongoClient(MONGODB_URL)
db=client[MONGODB_DB]


##这里使用PhantomJS，并配置了一些参数
browser=webdriver.PhantomJS(service_args=SERVICE_ArGS)

##窗口的大小，不设置的话，默认太小，会有问题
browser.set_window_size(1400,900)

wait=WebDriverWait(browser, 10)


def search():

    print('正在搜索')
##容易出现超时的错误
    try:
##等待这两个模块都加载好
        browser.get("https://www.taobao.com")
        input = wait.until(
                EC.presence_of_element_located((By.CSS_SELECTOR, '#q'))
            )
        submit=wait.until(
                EC.element_to_be_clickable((By.CSS_SELECTOR, '#J_TSearchForm > div.search-button > button'))
            )

        ######这块python2搞得鬼
        #input.send_keys('\u7f8e\u98df'.decode("unicode-escape"))
        input.send_keys(KEYWORD.decode("unicode-escape"))
        submit.click()

        total = wait.until(
                EC.presence_of_element_located((By.CSS_SELECTOR, '#mainsrp-pager > div > div > div > div.total'))
            )
        get_product()
        return total.text
    except TimeoutException:
        return search()

def next_page(page_number):

    print('翻页'+str(page_number))
    try:
        input = wait.until(
                    EC.presence_of_element_located((By.CSS_SELECTOR, '#mainsrp-pager > div > div > div > div.form > input'))
                )
        submit=wait.until(
                EC.element_to_be_clickable((By.CSS_SELECTOR, '#mainsrp-pager > div > div > div > div.form > span.btn.J_Submit'))
            )

        input.clear()
        input.send_keys(page_number)
        submit.click()

##判断是否翻页成功  高亮的是不是输入的值，直接加在后面即可
        wait.until(EC.text_to_be_present_in_element((By.CSS_SELECTOR,'#mainsrp-pager > div > div > div > ul > li.item.active > span'),str(page_number)))

        get_product()

    except TimeoutException:
        return next_page(page_number)

#获取产品信息
def get_product():
    products = wait.until(
       EC.presence_of_element_located((By.CSS_SELECTOR, '#mainsrp-itemlist .m-itemlist .items'))
                )
##拿到网页
    html = browser.page_source
    soup = BeautifulSoup(html,'lxml')
    items = soup.select('#mainsrp-itemlist .m-itemlist .items .item.J_MouserOnverReq')#

    print('*************************到此*************')
    for item in items:
        img = item.select('.J_ItemPic.img')[0].get('src')
        price = item.select('.price.g_price.g_price-highlight > strong')[0].get_text()
        deal = item.select('.deal-cnt')[0].get_text()
        title= item.select('.row.row-2.title > a ')[0].get_text().strip()  #:nth-of-type(3)
        shop = item.select('.row.row-3.g-clearfix > .shop > a > span:nth-of-type(2)')[0].get_text() 
        location = item.select('.location')[0].get_text()

        product={
            'img':img,
            'price':price,
            'deal':deal,
            'title':title,
            'shop':shop,
            'location':location
        }

#打印一下
        import json
        j = json.dumps(product)
        dict2  = j.decode("unicode-escape")
        print dict2

        save_to_mongo(product)


def save_to_mongo(product):
    try:
        if db[MONGODB_TABLE].insert(product):
            print('存储到mongodb成功'+str(product))
    except Exception:
        print("存储到mongodb失败"+str(product))



def main():

    try:
        total=search()

        ##搜寻  re正则表达式
        s=re.compile('(\d+)')
        total=int(s.search(total).group(1))
        for i in range(2,total+1):
            next_page(i)
    except Exception:
        print('出错')
    finally:
        browser.close()

if __name__ == '__main__':
    main()

config.py

MONGODB_URL='localhost'
MONGODB_DB='taobao'
MONGODB_TABLE='meishi'

SERVICE_ArGS=['--load-images=false','--disk-cache=true']

##就是美食这两个字，直接用汉字会报错
KEYWORD='\u7f8e\u98df'