使用python进行钉钉机器人的消息发送

#!/usr/bin/python3
import time
import hmac
import hashlib
import base64
import urllib.parse
import os

timestamp = str(round(time.time() * 1000))
secret = ‘SEC××××××××××××××××××××××××××××××××××××××××××ב
secret_enc = secret.encode(‘utf-8‘)
string_to_sign = ‘{}\n{}‘.format(timestamp, secret)
string_to_sign_enc = string_to_sign.encode(‘utf-8‘)
hmac_code = hmac.new(secret_enc, string_to_sign_enc, digestmod=hashlib.sha256).digest()
sign = urllib.parse.quote_plus(base64.b64encode(hmac_code))
#print(timestamp)
#print(sign)
webhookurl = ‘https://oapi.dingtalk.com/robot/send?access_token=×××××××××××××××××××××××××××××××××ב + ‘&timestamp=‘ + timestamp + ‘&sign=‘ + sign
os.environ[‘url‘] = webhookurl
#os.environ[‘xiantime‘] = time.strftime(‘%H:%M:%S‘)
os.environ[‘xiantime‘] = time.ctime()
os.system(‘‘‘ curl ${url} -H ‘Content-Type: application/json‘ -d ‘{"msgtype": "text","text":{"content":"现在时间是 ‘"$xiantime"‘   ！"}}‘ ‘‘‘)
#print(webhookurl)