site healthcheck to slack notification pipeline

site-healthcheck-to-slack-notification-pipeline.groovy

/*
 * site healthcheck to slack notification pipeline
 * 
 */
pipeline {
  agent any
  triggers {
    pollSCM('H/10 * * * *') // every 10 min
  }
  environment {
    NOTRACE = '#!/bin/sh -e\n'
    slack_webhook = 'https://hooks.slack.com/services/XXXXX/YYYY/XXXX' //
    channel = "#your_channnel"
    RUN_STATUS = "RUNNING"
  }
  parameters{
    string(defaultValue: 'http://your_site_healthcheck_url/', name: 'url', description: 'server health check url')
  }
  stages {
    stage("get previous healthcheck"){
      steps{
        script{
	  if(fileExists('health.txt')){
	    prevStatus = readFile "health.txt"
	  }else{ // init
	    prevStatus = RUN_STATUS
	  }
	  println "prevStatus: $prevStatus"
	}
      }
    }
    stage("run healthcheck crowd"){
        steps {
            script{
	      changed = false
	      curStatus = 'FAILURE'
              try{
                txt = sh(returnStdout: true, script: NOTRACE + "curl -s --connect-timeout 3 $params.url").trim()
		
                if(txt.contains(RUN_STATUS)){
		  curStatus = RUN_STATUS
		  RESULT = "returned $RUN_STATUS"
                }else{
		  println txt 		
		  def matcher = txt =~ /(?ms).*<title>(.*)<\/title>.*/
		  
		  if( matcher.matches()){
		    RESULT = "${matcher[0][1]}"
		  }else{
		    RESULT = txt
		  }
                }
              }catch(exc){
	        println exc
		if(exc.message.contains("exit code 28")){ // curl timeout error code https://ec.haxx.se/usingcurl-returns.html
		  RESULT = "connection timeout"
		}else{
	          RESULT = exc.message
		}
              }
	      println "curStatus: $curStatus"
	      if(!curStatus.equals(prevStatus)){
	        changed = true
	      }
            }
        }
    }
  }//stages
  post {
        always  {
	  script{
	    if(changed){
		    msg = "site status . $params.url ${RESULT}"
		    title = "site status is $curStatus"
		    payload="payload={ \"channel\": \"$channel\", \"text\": \"$title \n$msg\" }"
		    println payload
		    writeFile file: 'health.txt', text: curStatus
		    sh( script: NOTRACE+"curl -s -X POST -i $SLACK_WEBHOOK -d '$payload'" )
	    }//if
	  }
        }
  }  
}