追蹤一系列網址，並檢查是否有更新

checksiteupdate.py

import os
import hashlib
import urllib.request
import json
import codecs
import ssl

ssl._create_default_https_context = ssl._create_unverified_context


#輸入想要追蹤的網址，可以增加或刪除
site=['http://news.rthk.hk/rthk/ch/latest-news.htm',
      'https://www.mtr.com.hk/ch/corporate/news/corporate.php',
      'http://www.info.gov.hk/gia/general/ctoday.htm',
      'https://www.hkma.gov.hk/eng/publications-and-research/research/research-memorandums/2018.shtml'
      
     
     ]


#檢查json檔案是否存在，若沒有則建立一個
try:
    my_file = open('sitechange.json')
except IOError:
    data={}
    with open('sitechange.json','w') as outfile:
        json.dump(data, outfile, ensure_ascii=False)

    
#開啟json檔案，讀入資料
with open("sitechange.json") as infile:
    data = infile.read()
    local_data = json.loads(data)

#檢查json檔中是否有相關網址紀錄，若沒有則建立一個
for i in range(len(site)):
    if site[i] not in local_data:
        local_data[site[i]]=""

#若用戶刪除網址紀錄，則更新json檔
temp=local_data.copy()
for i in local_data.keys():
    if i not in site:
        temp.pop(i)

local_data=temp


#讀入相關網址，並找出其雜湊值，與已儲存的雜湊值進行對比
for i in range(len(site)):
    remote_data = urllib.request.urlopen(site[i]).read()
    remote_hash = hashlib.md5(remote_data).hexdigest()

    if remote_hash == local_data[site[i]]:
        print(site[i]+' has no update')
    else:
        print(site[i]+' is modified')
        local_data[site[i]]=remote_hash

#把更新的雜湊值寫回json檔
with open('sitechange.json','w') as outfile:
    json.dump(local_data, outfile, ensure_ascii=False)