PHPMailer: Mass Emails - Send all variable messages at once, instead of individually - php

Question

i'm currently trying to figure out the best way to do this.
The current system i've made sends email one by one and fills in the information for each entry as in the array, such as email, first name and last name.
The problem here is if i send alot of messages it takes forever to run through as it's calling a function everytime, instead i want it to send them all at once through one single function.
I know you can add multiple to's but then the body of the email won't send the correct information relative to each email. If anyone can help me with this i'd really appreciate it, as i've searched all over for a solution.
<?php
require '../phpmailer/PHPMailerAutoload.php';?>
<?php
/* Block List */
$blocklist = array('emailblocked#gmail.com', 'emailblocked2#gmail.com');
$emaillist = array(
array(
'Email'=>'example#gmail.com',
'First Name'=>'John',
'Last Name'=>'Doe'
),
array(
'Email'=>'example2#gmail.com',
'First Name'=>'Joe',
'Last Name'=>'Doe'
),
array(
'Email'=>'example3#gmail.com',
'First Name'=>'Jane',
'Last Name'=>'Doe'
),
);
foreach($emaillist as $emailkey){
if (in_array($emailkey['Email'], $blocklist)) {
echo 'Message has been been blocked for '.$emailkey['Email'].'<br>';
}else{
$mail = new PHPMailer;
// $mail->SMTPDebug = 3; // Enable verbose debug output
$mail->isSMTP(); // Set mailer to use SMTP
$mail->Host = 'smtp.mandrillapp.com'; // Specify main and backup SMTP servers
$mail->SMTPAuth = true; // Enable SMTP authentication
$mail->Username = 'username#example.com'; // SMTP username
$mail->Password = 'passwordgoeshere'; // SMTP password
$mail->SMTPSecure = 'tls'; // Enable TLS encryption, `ssl` also accepted
$mail->Port = 587; // TCP port to connect to
$mail->From = 'noreply#example.com';
$mail->FromName = 'Example';
$mail->addAddress($emailkey['Email'], $emailkey['First Name'].' '.$emailkey['Last Name']); // Add a recipient
$mail->addReplyTo('info#example.com', 'Information');
$mail->isHTML(true); // Set email format to HTML
$mail->Subject = $emailkey['First Name'].' '.$emailkey['Last Name'];
$emailtemp = file_get_contents('templates/temp-1.html');
$emailtempfilteremail = str_replace("[[email]]", $emailkey['Email'], $emailtemp);
$emailtempfilterfirstname = str_replace("[[firstname]]", $emailkey['First Name'], $emailtempfilteremail);
$emailtempfilterlastname = str_replace("[[lastname]]", $emailkey['Last Name'], $emailtempfilterfirstname);
$mail->Body = $emailtempfilterlastname;
$mail->AltBody = 'This is a spicy email!';
if(!$mail->send()) {
echo 'Message could not be sent.';
echo 'Mailer Error: ' . $mail->ErrorInfo;
} else {
echo 'Message has been sent to '.$emailkey['Email'].'<br>';
}
$mail->ClearAllRecipients();
}
}
?>
Thank you

Answer 1

There's an example of how to send to a list from a database efficiently in the examples bundled with PHPMailer. There's nothing inherently likely to get you blacklisted by using PHPMailer for sending large volumes, but you do need to tread carefully. Mandrill isn't magic - it's as vulnerable as anything else to being blocked if you send spam through it.
If you want to send 50 simultaneously from PHP, fire up multiple processes with the pcntl extension, but it won't actually help you very much as you'll be increasing overhead enormously. You can set SMTPKeepAlive = true in PHPMailer which will reduce overhead a lot (it avoids making a new connection for every message), but it still won't send simultaneous messages - nothing will. There isn't an option in SMTP to send multiple messages with different bodies simultaneously on the same connection.
Sending to a big list during a page load in a browser is very unreliable; use a cron script or background process to do your actual sending and just set it up through your web interface. One tip if you are waiting for a page load - call ignore_user_abort() early on so that it won't stop sending if your browser closes the connection - and beware the page refresh! If you want to send much faster, install a local mail server like postfix and use that to relay - it will be far faster and more reliable than sending directly.

Answer 2

Yes, it is possible with a modification of your code, the problem is not with the PHPMailer itself, but with your approach. You should avoid using an new instance of the class inside a loop (this leads to memory exhaustion with large lists), instead, only invoke $mail->addAddress(...) or $mail->Subject(...) inside the foreach loop.
If you read the source code of the PHPMailer, you will notice how exactly the functions addAddress(), Subject() or Body() works.
Your code should look something like this:
<?php
/*Move your "generic" initialization outside the loop*/
$mail = new PHPMailer;
// $mail->SMTPDebug = 3; // Enable verbose debug output
$mail->isSMTP(); // Set mailer to use SMTP
$mail->Host = 'smtp.mandrillapp.com'; // Specify main and backup SMTP servers
$mail->SMTPAuth = true; // Enable SMTP authentication
$mail->Username = 'username#example.com'; // SMTP username
$mail->Password = 'passwordgoeshere'; // SMTP password
$mail->SMTPSecure = 'tls'; // Enable TLS encryption, `ssl` also accepted
$mail->Port = 587; // TCP port to connect to
$mail->From = 'noreply#example.com';
$mail->FromName = 'Bet Monkey';
$mail->isHTML(true); // Set email format to HTML
$mail->addReplyTo('info#example.com', 'Information');
$emailtemp = file_get_contents('templates/temp-1.html');
$mail->AltBody = 'This is a spicy email!';
/*Start the loop by adding email addresses*/
foreach($emaillist as $emailkey){
if (in_array($emailkey['Email'], $blocklist)) {
echo 'Message has been been blocked for '.$emailkey['Email'].'<br>';
}else{
$mail->addAddress($emailkey['Email'], $emailkey['First Name'].' '.$emailkey['Last Name']); // Add a recipient
$mail->Subject = $emailkey['First Name'].' '.$emailkey['Last Name'];
$emailtempfilteremail = str_replace("[[email]]", $emailkey['Email'], $emailtemp);
$emailtempfilterfirstname = str_replace("[[firstname]]", $emailkey['First Name'], $emailtempfilteremail);
$emailtempfilterlastname = str_replace("[[lastname]]", $emailkey['Last Name'], $emailtempfilterfirstname);
$mail->Body = $emailtempfilterlastname;
if(!$mail->send()) {
echo 'Message could not be sent.';
echo 'Mailer Error: ' . $mail->ErrorInfo;
} else {
echo 'Message has been sent to '.$emailkey['Email'].'<br>';
}
$mail->ClearAllRecipients();
}
}
Using the above approach I personally have send hundreds of thousands emails, but, as they say in the comments - you'll risking to be blacklisted (you can check here or here for details).