Application scenario

Regularly request the website / API, judge whether the service is available and whether the website is down according to the request response, and send a SMS to inform the administrator when there is a down time

engineering service

Operation platform: Alibaba cloud functional computing
Development language: Python 3 (small function, simplified, fast development, code can be edited online on Alibaba cloud)
Other: Alibaba cloud SMS interface

Why function calculation?

1. No need to pay attention to O & M, just write core code, a python script is enough (Alibaba cloud can edit code online, and local development environment does not need to be built)
2. For timing detection, only the "timing trigger" of function calculation is needed
3. Based on the number of calls and running time of the code (the relative price should be very low)

process

1. Alibaba cloud opens function computing service
2. Create service: function calculation - create service: httpchk
3. Create function: language Python - Blank function
4. Create function: trigger timing trigger: httpchk trigger time interval 1 minute
5. Create function: function name: httpchk FC,
6. Creating functions: code by: editing Online
7. Create function: function execution memory: 128MB (enough)

Function code:

# -*- coding: utf-8 -*-
import logging
import requests
from aliyunsdkcore.client import AcsClient
from aliyunsdkcore.request import CommonRequest

# Web address to be detected, only GET requests are supported
urls = ["https://www.baidu.com","http://www.mtain.top"]
# Mobile number to receive SMS notification
phone = "180000000"

# Alibaba cloud SMS interface information
accessKeyId = 'xxxx'
accessSecret = 'xxxx'
signName = 'xxxxx'
templateCode = 'SMS_xxxx'
logger = logging.getLogger()

def handler(event, context):
  for url in urls:
    do_httpchk(url)

def do_httpchk(url):
  logger.info('Testing website:{}'.format(url))
  try:
    req=requests.get(url)
    logger.info('website:{}Normal response,Return data length:{}'.format(url,len(req.text)))
  except Exception as e:
    logger.error('website:{}Service exception,{}'.format(url,e))
    send_sms()
    
def send_sms():
  client = AcsClient(accessKeyId, accessSecret, 'default')
  request = CommonRequest()
  request.set_accept_format('json')
  request.set_domain('dysmsapi.aliyuncs.com')
  request.set_method('POST')
  request.set_protocol_type('https') # https | http
  request.set_version('2017-05-25')
  request.set_action_name('SendSms')
    
  request.add_query_param('PhoneNumbers', phone)
  request.add_query_param('SignName', signName)
  request.add_query_param('TemplateCode', templateCode)
  # Alibaba cloud SMS variable [a-zA-Z0-9] with length less than 20
  web_name = url.replace('https://','').replace('http://','').replace('.','0')[0:18]
  request.add_query_param('TemplateParam', '{"code":"'+web_name+'"}')
  
  response = client.do_action(request)
  logger.info('Send SMS Response:'+str(response, encoding = 'utf-8'))