Ping site and return result in PHP

问题:

I'd like to create a small IF procedure that will check if Twitter is available (unlike now, for example), and will return true or false.

Help :)

回答1:

function urlExists($url=NULL)  
{  
    if($url == NULL) return false;  
    $ch = curl_init($url);  
    curl_setopt($ch, CURLOPT_TIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);  
    $data = curl_exec($ch);  
    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);  
    curl_close($ch);  
    if($httpcode>=200 && $httpcode<300){  
        return true;  
    } else {  
        return false;  
    }  
}  

This was grabbed from this post on how to check if a URL exists. Because Twitter should provide an error message above 300 when it is in maintenance, or a 404, this should work perfectly.

回答2:

Here's one:

http://www.planet-source-code.com/vb/scripts/ShowCode.asp?lngWId=8&txtCodeId=1786

Another:

function ping($host, $port, $timeout) { 
  $tB = microtime(true); 
  $fP = fSockOpen($host, $port, $errno, $errstr, $timeout); 
  if (!$fP) { return "down"; } 
  $tA = microtime(true); 
  return round((($tA - $tB) * 1000), 0)." ms"; 
}

//Echoing it will display the ping if the host is up, if not it'll say "down".
echo ping("www.google.com", 80, 10);  

回答3:

Using shell_exec:

<?php
$output = shell_exec('ping -c1 google.com');
echo "<pre>$output</pre>";
?>

回答4:

Another option (if you need/want to ping instead of send an HTTP request) is the Ping class for PHP. I wrote it for just this purpose, and it lets you use one of three supported methods to ping a server (some servers/environments only support one of the three methods).

Example usage:

require_once('Ping/Ping.php');
$host = 'www.example.com';
$ping = new Ping($host);
$latency = $ping->ping();
if ($latency) {
  print 'Latency is ' . $latency . ' ms';
}
else {
  print 'Host could not be reached.';
}

回答5:

ping is available on almost every OS. So you could make a system call and fetch the result.

回答6:

With the following function you are just sending the pure ICMP packets using socket_create. I got the following code from a user note there. N.B. You must run the following as root.

Although you can't put this in a standard web page you can run it as a cron job and populate a database with the results.

So it's best suited if you need to monitor a site.

function twitterIsUp() {
    return ping('twitter.com');
}

function ping ($host, $timeout = 1) {
    /* ICMP ping packet with a pre-calculated checksum */
    $package = "\x08\x00\x7d\x4b\x00\x00\x00\x00PingHost";
    $socket = socket_create(AF_INET, SOCK_RAW, 1);
    socket_set_option($socket, SOL_SOCKET, SO_RCVTIMEO, array('sec' => $timeout, 'usec' => 0));
    socket_connect($socket, $host, null);

    $ts = microtime(true);
    socket_send($socket, $package, strLen($package), 0);
    if (socket_read($socket, 255)) {    
        $result = microtime(true) - $ts;
    } else {
        $result = false;
    }
    socket_close($socket);

    return $result;
}

回答7:

this is php code I used, reply is usually like this:

    2 packets transmitted, 2 received, 0% packet loss, time 1089ms

So I used code like this:

  

    $ping_how_many = 2;
    $ping_result = shell_exec('ping -c '.$ping_how_many.' bing.com');
    if( !preg_match('/'.$ping_how_many.' received/',$ping_result) ){
       echo 'Bad ping result'. PHP_EOL;
        // goto next1;
    }