2019年12月20日
一.基本思路
1.抓取数据
2..检测数据是否更新（md5实现）
3.分析数据
4.保存数据
5.爬虫工作计划任务
二.具体实现
1.检验更新
# coding=utf-8
"""项目实战：抓取纳斯达克股票数据"""
import urllib.request
import hashlib
from bs4 import BeautifulSoup
import os
url = 'https://www.nasdaq.com/symbol/aapl/historical#.UWdnJBDMhHk'
def validateUpdate(html):
"""验证数据是否更新，更新返回True，未更新返回False"""
# 创建md5对象
md5obj = hashlib.md5()
md5obj.update(html.encode(encoding='utf-8'))
md5code = md5obj.hexdigest()
print(md5code)
old_md5code = ''
f_name = 'md5.txt'
if os.path.exists(f_name): # 如果文件存在读取文件内容
with open(f_name, 'r', encoding='utf-8') as f:
old_md5code = f.read()
if md5code == old_md5code:
print('数据没有更新')
return False
else:
# 把新的md5码写入到文件中
with open(f_name, 'w', encoding='utf-8') as f:
f.write(md5code)
print('数据更新')
return True
req = urllib.request.Request(url)
with urllib.request.urlopen(req) as response:
data = response.read()
html = data.decode()
sp = BeautifulSoup(html, 'html.parser')
# 返回指定CSS选择器的div标签列表
# div = sp.select('div#quotes_content_left_pnlAJAX')
div = sp.select('div.historical-data__table-container')
# 从列表中返回第一个元素
divstring = div[0]
if validateUpdate(divstring): # 数据更新
pass
# TODO 分析数据
# TODO 保存数据到数据库
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2.分析数据
2.1花去抓取字段
image.png
html.js body.path-market-activity.with-header-ads.with-header-ads--loaded div.dialog-off-canvas-main-canvas div.page.with-primary-nav.with-sub-nav main.page__main div.page__content div.quote-subdetail__content div.layout.layout--2-col-large div.layout--main div.historical-data div.historical-data__data.loaded div.historical-data__table-container table.historical-data__table tbody.historical-data__table-body tr.historical-data__row
html.js body.path-market-activity.with-header-ads.with-header-ads--loaded div.dialog-off-canvas-main-canvas div.page.with-primary-nav.with-sub-nav main.page__main div.page__content div.quote-subdetail__content div.layout.layout--2-col-large div.layout--main div.historical-data div.historical-data__data.loaded div.historical-data__table-container table.historical-data__table tbody.historical-data__table-body tr.historical-data__row
该网站已经改成动态数据获取的，具体参考下面完整例子代码
5.爬虫工作计划任务
image.png
三完整例子代码
# coding=utf-8
"""项目实战：抓取纳斯达克股票数据"""
import datetime
import hashlib
import logging
import os
import threading
import time
import urllib.request
import json
from com.pkg1.db.db_access import insert_hisq_data
logging.basicConfig(level=logging.INFO,
format='%(asctime)s - %(threadName)s - '
'%(name)s - %(funcName)s - %(levelname)s - %(message)s')
logger = logging.getLogger(__name__)
url = 'https://api.nasdaq.com/api/quote/AAPL/historical?assetclass=stocks&fromdate=2019-01-01&limit=18&todate=2019-12-20'
def validateUpdate(html):
"""验证数据是否更新，更新返回True，未更新返回False"""
# 创建md5对象
md5obj = hashlib.md5()
md5obj.update(html.encode(encoding='utf-8'))
md5code = md5obj.hexdigest()
old_md5code = ''
f_name = 'md5.txt'
if os.path.exists(f_name): # 如果文件存在读取文件内容
with open(f_name, 'r', encoding='utf-8') as f:
old_md5code = f.read()
if md5code == old_md5code:
logger.info('数据没有更新')
return False
else:
# 把新的md5码写入到文件中
with open(f_name, 'w', encoding='utf-8') as f:
f.write(md5code)
logger.info('数据更新')
return True
# 线程运行标志
isrunning = True
# 爬虫工作间隔
interval = 5
def controlthread_body():
"""控制线程体函数"""
global interval, isrunning
while isrunning:
# 控制爬虫工作计划
i = input('输入Bye终止爬虫，输入数字改变爬虫工作间隔，单位秒：')
logger.info('控制输入{0}'.format(i))
try:
interval = int(i)
except ValueError:
if i.lower() == 'bye':
isrunning = False
def istradtime():
"""判断交易时间"""
# return False
now = datetime.datetime.now()
df = '%H%M%S'
strnow = now.strftime(df)
starttime = datetime.time(9, 30).strftime(df)
endtime = datetime.time(15, 30).strftime(df)
if now.weekday() == 5 \
or now.weekday() == 6 \
or (strnow < starttime or strnow > endtime):
# 非工作时间
return False
# 工作时间
return True
def validate_price(oriPrice):
if oriPrice.find('$') >= 0:
oriPrice = oriPrice.replace('$', '')
return oriPrice
def workthread_body():
"""工作线程体函数"""
global interval, isrunning
while isrunning:
if istradtime():
# 交易时间内不工作
logger.info('交易时间，爬虫休眠1小时...')
time.sleep(60 * 60)
continue
logger.info('爬虫开始工作...')
req = urllib.request.Request(url)
with urllib.request.urlopen(req) as response:
data = response.read()
html = data.decode('gbk')
print(html)
py_dict = json.loads(html)
divstring = html
if validateUpdate(divstring): # 数据更新
# 分析数据
trlist = py_dict['data']['tradesTable']['rows']
data = []
for tr in trlist:
rows = tr
fields = {}
try:
df = '%m/%d/%Y'
fields['Date'] = datetime.datetime.strptime(rows["date"], df)
except ValueError:
# 实时数据不分析（只有时间，如10:12）
continue
fields['Open'] = float(validate_price(rows["open"]))
fields['High'] = float(validate_price(rows["high"]))
fields['Low'] = float(validate_price(rows["low"]))
fields['Close'] = float(validate_price(rows["close"]))
fields['Volume'] = int(rows["volume"].replace(',', ''))
data.append(fields)
# 保存数据到数据库
for row in data:
row['Symbol'] = 'AAPL'
insert_hisq_data(row)
# 爬虫休眠
logger.info('爬虫休眠{0}秒...'.format(interval))
time.sleep(interval)
def main():
"""主函数"""
global interval, isrunning
# 创建工作线程对象workthread
workthread = threading.Thread(target=workthread_body, name='WorkThread')
# 启动线程workthread
workthread.start()
# 创建控制线程对象controlthread
controlthread = threading.Thread(target=controlthread_body, name='ControlThread')
# 启动线程controlthread
controlthread.start()
if __name__ == '__main__':
main()
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