使用 cron 作业检查网络服务器状态的 PHP 脚本

Question

我正在寻找可以在我的网络主机上作为 cron 作业运行的 PHP 脚本。它需要遍历网站列表并检查以确保每个网站都返回 Http 响应 200 OK。如果网站未返回该响应或不可用，则需要向网站管理员发送电子邮件。

Answer 1

此后我改进了此脚本以检查您的网站/网络服务器是否仍在运行。我稍微改进了错误处理并添加了一封安慰电子邮件，让您知道脚本已成功运行。

安慰电子邮件依赖于另一个名为 healthcheck.txt 的文件来存储一些值，直到脚本下次运行为止。如果它没有自动创建，只需创建一个 0 字节的文本文件，上传它并为其设置正确的文件权限(读/写)。

<?php
// set email server parameters
ini_set('sendmail_from', 'server.status@host.example.com' );
ini_set('SMTP', '127.0.0.1' );
ini_set('smtp_port', '25' );

ini_set('allow_url_fopen', true); //enable fopen

// define list of webservers to check
$webservers = array('www.example.com', 'www.example2.com');

function sendemail($subject,$message) // email function using standard php mail
{
$wrapmessage = wordwrap($message,70,"\n",true); // mail function can't support a message more than 70 characters per line
$to = 'you@example.com'; // who to send the emails to
// Headers ensure a properly formatted email
$headers = 'From: server.status@host.example.com' . "\r\n" .
    'Reply-To: server.status@host.example.com' . "\r\n" .
    'X-Mailer: PHP/' . phpversion();

return mail($to, $subject, $wrapmessage, $headers); //send the email
}

function getresponse($url) //queries a url and provides the header returned and header response
{
$ch = curl_init(); // create cURL handle (ch)
if (!$ch) { // send an email if curl can't initialise
    $subject = "Web Server Checking Script Error";
    $message = "The web server checking script issued an error when it tried to process ".$url.". Curl did not initialise correctly and issued the error - ".curl_error($ch)." The script has died and not completed any more tasks.";
    sendemail($subject,$message);
    die();
}
// set some cURL options
$ret = curl_setopt($ch, CURLOPT_URL, "http://".$url."/");
$ret = curl_setopt($ch, CURLOPT_FRESH_CONNECT, true);   
$ret = curl_setopt($ch, CURLOPT_HEADER, true);
$ret = curl_setopt($ch, CURLOPT_NOBODY, true);
$ret = curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$ret = curl_setopt($ch, CURLOPT_RETURNTRANSFER, false);
$ret = curl_setopt($ch, CURLOPT_TIMEOUT, 30);

// execute
$ret = curl_exec($ch);

if (empty($ret)) {
    // some kind of an error happened
    $subject = "Web Server Checking Script Error";
    $message = "The web server checking script issued an error when it tried to process ".$url.". Curl was trying to execute and issued the error - ".curl_error($ch)." Further URLs will be tried.";
    sendemail($subject,$message);
    curl_close($ch); // close cURL handler
    } else {
        $info = curl_getinfo($ch); //get header info - output is an array
        curl_close($ch); // close cURL handler

        if (empty($info['http_code'])) {
                $subject = "Web Server Checking Script Error";
                $message = "The web server checking script issued an error when it tried to process ".$url."\r\nNo HTTP code was returned";
                sendemail($subject,$message);
        } else {
            // load the HTTP code descriptions
            $http_codes = parse_ini_file("/server/path/to/http-response-codes.ini");

            // results - code number and description
            $result = $info['http_code'] . " " . $http_codes[$info['http_code']];
        return $result; // $result contained a code, so return it
        }
    return None; //$info was empty so return nothing
    }
return None; // $ret was empty so return nothing
}

// this bit of code initiates the checking of the web server
foreach ($webservers as $webserver) { //loop through the array of webservers
    $status = getresponse($webserver); //get the status of the webserver
        if (empty($status)) {
        // nothing happens here because if $status is empty, the function returned nothing and an email was already sent.
        } else {
            if (strstr($status, "200")) { //search for the error code that means everything is ok
            // If found, don't do anything, just process the next one
            } else {
                $timestamp = date("m/d/Y H:i:s a", time()); //get the current date and time
                $error = $webserver." - ".$status." status error detected"; //set error message with server and response code
                $message = "At - ".$timestamp." - a http response error was detected on ".$webserver.".\r\nInstead of a 200 OK response, the server returned ".$status."\r\nThis requires immediate attention!"; //At what time was an error detected on which server and what was the error message
                sendemail($error,$message); //trigger the sendemail function
            }
        }
}

// Health Check. Comfort email twice a day to show script is actually running.
$healthfile = "/server/path/to/healthcheck.txt"; // path with the name of the file to store array data
$hfsize = filesize($healthfile); // filesize of healthcheck file
$notify = "16:00"; // specify the earliest time in the day to send the email - cron job settings dictate how close you'll get to this
$datenow = date("d-m-Y"); //what is current date as of now

if (file_exists($healthfile) && $hfsize !== 0) { //read contents of array from file if it exists and has data, otherwise create array with some defaults
    $valuestor = unserialize(file_get_contents($healthfile));
    } else { // file doesn't exist so we'll create an array with some defaults
    $valuestor = array("email_sent"=>0, "sent_date"=>$datenow, "iterations"=>0);
}
$i = $valuestor['iterations']; //get the iterations number from the valuestor array
$curdate = strtotime($datenow); //convert current date to seconds for comparison
$stordate = strtotime($valuestor['sent_date']); //convert stored date to seconds
if ($valuestor['email_sent'] == 1) { // has the email already been sent today
    if ($curdate == $stordate) { // if it has, is the current date equal to the stored date
        $i++; // yes it is, just increment the iterations
    } else { // it's a new day, reset the array
        $timestamp = date("m/d/Y H:i:s a", time()); //get the current date and time
        $subject = "Web Server Checking Script Health Status"; //set email subject line
        $message = "Message created: ".$timestamp."\r\nThe Web Server Checking script ran successfully for ".$i." time(s) on the ".$valuestor['sent_date']; //email message
        sendemail($subject,$message); //trigger the sendemail function
        $valuestor['email_sent'] = 0; // set email sent to false
        $valuestor['sent_date'] = $datenow; // set email send date to today
        $i = 1; // this is the first time the script has run today, so reset i to 1. It gets written to the array later.
        // echo $message;
    }
} else { // email has not been sent today
    $checktime = strtotime($notify); //convert $notify time (for current date) into seconds since the epoch
    if (time() >= $checktime) { // are we at or have we gone past checktime
        $i++; // increase the number of script iterations by 1
        $timestamp = date("m/d/Y H:i:s a", time()); //get the current date and time
        $subject = "Web Server Checking Script Health Status"; //set email subject line
        $message = "Message created: ".$timestamp."\r\nThe Web Server Checking script has successfully run and completed ".$i." time(s) today."; //email message
        sendemail($subject,$message); //trigger the sendemail function
        $valuestor['email_sent'] = 1; // set array to show that email has gone
        // echo $message;
    } else { // we haven't reached the check time yet
    $i++; // just increment the iterations
    }
}
$valuestor['iterations'] = $i; // update the array with the iterations number

// save the array to the file again
$fp = fopen($healthfile, 'w+'); // open or create the file, clear its contents and write to it
if (!$fp) { // handle the error with an email if the file won't open
$subject = "Web Server Checking Script Error";
$message = "The web server checking script issued an error when trying to open or create the file ".$healthfile." The script was ended without any new information being stored.";
sendemail($subject,$message);
} else {
fwrite($fp, serialize($valuestor)); // write to the file and serialise the array valuestor
fclose($fp); // close the file connection
} 
die(); // make sure that script dies and cron job terminates
?>