Bedste måde at sende mails

mail() funktionen i PHP åbner og lukker forbindelsen til en evt. smtp-server hver eneste gang du kalder den - hvis du sender mange mails på denne måde - altså kalder mail() mange gange, vil du selvfølgelig også åbne og lukke forbindelsen til smtp-serveren mange (unødvendige) gange!

Derfor er der mest fornuft i selv at åbne en forbindelse til smtp-serveren, sende alle de mails der skal sendes og derefter lukke forbindelsen igen. Dette belaster smtp-serveren mindst muligt.

Hvis du skal sende mange mails på en gang er det at foretrække at sende direkte via smtp-serveren i stedet for at bruge mail();

Her er en SMTP-klasse:

<?php


// smtp_client class -------------------------------------------------------
// use:
//        $smtp= new smtp_client();
//        $smtp->email($from, $to[0], $to_name[0], $header[0], $subject[0], $body[0]);
//        $smtp->email($from, $to[1], $to_name[1], $header[1], $subject[1], $body[1]);
//        $smtp->send();

class smtp_client {
    var $connection;
    var $server;
    var $elog_fp;
    var $log_file = './smtp_client.log';
    var $do_log = true;
   
    /* default constructor */
    function smtp_client($server = '') {
        if (!$server) {
            $this->server = 'localhost';
        } else {
            $this->server = $server;
        }
       
        $this->connection = fsockopen($this->server, 25);
       
        if ($this->connection <= 0) {
            return 0;
        }

        $this->elog(fgets($this->connection, 1024));
        $this->elog("HELO xyz\r\n", 1);
        fputs($this->connection, "HELO xyz\r\n");
        $this->elog(fgets($this->connection, 1024));
    }

    function email($from_mail, $to_mail, $to_name, $header, $subject, $body) {
        if ($this->connection <= 0) {
            return 0;
        }
   
        $this->elog("MAIL FROM:$from_mail", 1);
        fputs($this->connection, "MAIL FROM:$from_mail\r\n");
        $this->elog(fgets($this->connection, 1024));

        $this->elog("RCPT TO:$to_mail", 1);
        fputs($this->connection, "RCPT TO:$to_mail\r\n");
        $this->elog(fgets($this->connection, 1024));

        $this->elog("DATA", 1);
        fputs($this->connection, "DATA\r\n");
        $this->elog(fgets($this->connection, 1024));
   
        $this->elog("Subject: $subject", 1);
        $this->elog("To: $to_name", 1);
        fputs($this->connection, "Subject: $subject\r\n");
        fputs($this->connection, "To: $to_name\r\n");

        if ($header) {
            $this->elog($header, 1);
            fputs($this->connection, "$header\r\n");
        }

        $this->elog('', 1);
        $this->elog($body, 1);
        $this->elog('.', 1);
        fputs($this->connection, "\r\n");
        fputs($this->connection, "$body \r\n");
        fputs($this->connection, ".\r\n");
        $this->elog(fgets($this->connection, 1024));

        return 1;
    }

    function send() {
        if ($this->connection) {
            fputs($this->connection, "QUIT\r\n");
            fclose($this->connection);
            $this->connection = 0;
        }
    }

    function close() {
        $this->send();
    }

    function elog($text, $mode = 0) {
        if (!$this->do_log) {
            return;
        }

        /* Open file */
        if (!$this->elog_fp) {
            if (!($this->elog_fp = fopen($this->log_file, 'a'))) {
                return;
            }
            fwrite($this->elog_fp, "\n-------------------------------------------\n");
            fwrite($this->elog_fp, " Sent " . date("Y-m-d H:i:s") . "\n");
            fwrite($this->elog_fp, "-------------------------------------------\n");
        }

        /* Write to log */
        if (!$mode) {
            fwrite($this->elog_fp, "    $text\n");
        } else {
            fwrite($this->elog_fp, "$text\n");
        }
    }
}

?>

Lukker og slukker, da min nye server alligevel har en mailinglist funktion !!!