1、项目流程

　　2、中心调度
# 中心调度
def main():
try:
total = search()
total = int(re.compile('.*?(d+).*?').search(total).group(1))
for i in range(2，total+1):
next_page(i)
except Exception as e:
print('异常')
finally:
browser.close()
　　3、模拟查询
# 根据关键字查询
def search():
try:
browser.get('https://www.taobao.com/')
# 直到搜索框加载出
input_search = wait.until(EC.presence_of_element_located((By.ID，'q')))
# 直到搜索按钮可以点击
submit_button = wait.until(EC.element_to_be_clickable((By.CLASS_NAME，'btn-search')))
input_search.send_keys(KEYWORDS)
submit_button.click()
total = wait.until(EC.presence_of_element_located((By.CSS_SELECTOR，'div.wraper  div.total')))
get_products()
return total.text
except TimeoutException as e:
print('响应超时')
　　4、下一页的操作
# 下一页爬取
def next_page(index):
try:
input = wait.until(EC.presence_of_element_located((By.CSS_SELECTOR，'#mainsrp-pager div.form > input')))
submit = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR，'#mainsrp-pager div.form > span.btn.J_Submit')))
input.clear()
input.send_keys(index)
submit.click()
wait.until(EC.text_to_be_present_in_element((By.CSS_SELECTOR，'#mainsrp-pager > div > div > div > ul > li.item.active > span')，str(index)))
get_products()
except NoSuchElementException as e:
print('元素未加载')
return next_page(index)
　　5、商品信息的解析
# 获取一页上所有的商品
def get_products():
wait.until(EC.presence_of_element_located((By.CSS_SELECTOR， "#mainsrp-itemlist .items .item")))
html = browser.page_source
doc = PyQuery(html)
items = doc('.m-itemlist .items  .item').items()
for item in items:
product = {
'image':item.find('.pic-link .img').attr('data-src')，
'price':float(item.find('.price').text()[2:])，
'deal':item.find('.deal-cnt').text()[:-3]，
'title':item.find('.title').text()，
'shop':item.find('.shop').text()，
'location':item.find('.location').text()，
'keywords':KEYWORDS
}
save_to_mongo(product=product)
　　6、完整代码
#!/usr/bin/python
# -*- coding: utf-8 -*-
import pymongo
import re
from pyquery import PyQuery
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import TimeoutException，NoSuchElementException
from setting import *
client = pymongo.MongoClient(MONGO_HOST)
db = client[MONGO_DB]
browser = webdriver.Chrome()
wait = WebDriverWait(browser，10)
# 根据关键字查询
def search():
try:
browser.get('https://www.taobao.com/')
# 直到搜索框加载出
input_search = wait.until(EC.presence_of_element_located((By.ID，'q')))
# 直到搜索按钮可以点击
submit_button = wait.until(EC.element_to_be_clickable((By.CLASS_NAME，'btn-search')))
input_search.send_keys(KEYWORDS)
submit_button.click()
total = wait.until(EC.presence_of_element_located((By.CSS_SELECTOR，'div.wraper  div.total')))
get_products()
return total.text
except TimeoutException as e:
print('响应超时')
# 下一页爬取
def next_page(index):
try:
input = wait.until(EC.presence_of_element_located((By.CSS_SELECTOR，'#mainsrp-pager div.form > input')))
submit = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR，'#mainsrp-pager div.form > span.btn.J_Submit')))
input.clear()
input.send_keys(index)
submit.click()
wait.until(EC.text_to_be_present_in_element((By.CSS_SELECTOR，'#mainsrp-pager > div > div > div > ul > li.item.active > span')，str(index)))
get_products()
except NoSuchElementException as e:
print('元素未加载')
return next_page(index)
# 获取一页上所有的商品
def get_products():
wait.until(EC.presence_of_element_located((By.CSS_SELECTOR， "#mainsrp-itemlist .items .item")))
html = browser.page_source
doc = PyQuery(html)
items = doc('.m-itemlist .items  .item').items()
for item in items:
product = {
'image':item.find('.pic-link .img').attr('data-src')，
'price':float(item.find('.price').text()[2:])，
'deal':item.find('.deal-cnt').text()[:-3]，
'title':item.find('.title').text()，
'shop':item.find('.shop').text()，
'location':item.find('.location').text()，
'keywords':KEYWORDS
}
save_to_mongo(product=product)
# 保存至mongoDB
def save_to_mongo(product):
try:
if db[MONGO_TABLE].insert(product):
print('保存成功'， product)
except Exception:
print('保存失败')
# 中心调度
def main():
try:
total = search()
total = int(re.compile('.*?(d+).*?').search(total).group(1))
for i in range(2，total+1):
next_page(i)
except Exception as e:
print('异常')
finally:
browser.close()
if __name__=='__main__':
main()
　　7、运行结果