A simple url monitor that monitor the status of the url and search the page for provided string, sends email notifications if the check fails

url-monitor.php

#!/usr/bin/php
<?php
// Use https://uptimerobot.com/ instead

define('CONTACT_TO', 'me@my.com');
define('CONTACT_FROM', 'report@my.com');
$message = '';
$subject = '';

if (count($argv) > 3)
    die("\n\t\t Script supports oly two parameters. Use like " . $argv[0] . " TEXT_PATTERN www.host.com\n\n\n");


$host = $argv[2];
$find = $argv[1];
if (!check())
    alert();

function alert() {
    global $host, $message, $subject;
    $to = CONTACT_TO;
    $headers = 'From: ' . CONTACT_FROM . "\r\n" .
            'X-Mailer: PHP/' . phpversion();

    /*
    echo "\nTo: ". CONTACT_TO;
    echo "\nFrom: ". CONTACT_FROM;
    echo "\nSubject: ". $subject;
    echo "\nMessage: \n". $message;
    echo "\n\n\n";
    */
    mail($to, $subject, $message, $headers);
}

function check() {
    global $host, $find, $message, $subject;
    $sh = curl_init($host);
    curl_setopt($sh, CURLOPT_HEADER, 0);
    curl_setopt($sh, CURLOPT_RETURNTRANSFER, 1); 
    $content = curl_exec($sh);
    $aCURLinfo = curl_getInfo($sh);
    curl_close($sh);

    $subject = "Status code not 200";
    $message = "\n\nURL:";
    $message .= "\n------------\n";
    $message .= " $host";
    $message .= "\n\n\nSearch:";
    $message .= "\n------------\n";
    $message .= " $find";
    $message .= "\n\n\nHeader Details:";
    $message .= "\n------------------------\n\n";
    $message .= print_r($aCURLinfo, true);
    
    if (!isset($aCURLinfo['http_code']) || ($aCURLinfo['http_code'] != 200))
	      return false;
        
    else if (strstr($content, $find) === false) {
        $subject = "Page Mismatch";
        $message .= "\n\n\n";
	      $message .= "\nURL:";
	      $message .= "\n------------\n";
	      $message .= " $host";
        $message .= "\n\n\nPage Content:";
        $message .= "\n------------------\n\n";
        $message .= print_r($content, true);
        $message .= "\n\n";
        return false;
    }
    return true;
}