Send form file attachment using PHP and Sendgrid APIs

Question

Below is a script used too send email through php sendmail using phpmailer. I want to send an email using Sendgrid's API, what changes do I need to make in order to make it work with Sendgrid?

<?php

require('PHPMailer/class.phpmailer.php');

if(isset($_POST['email'])) {
    $name = $_POST['name']; // required
    $position = $_POST['position']; // required
    $email_from = $_POST['email']; // required
    $phone = $_POST['phone']; // not required
    $comments = $_POST['comments']; // required

    $email_to = "careers@site.com";
    $name_to = "careers";
    $email_subject = "Job Application from ".$name." for ".$position;

  if($position != null)
    function clean_string($string) {
      $bad = array("content-type","bcc:","to:","cc:","href");
      return str_replace($bad,"",$string);
    }
     $email_message = "";
    $email_message .= "Name: ".clean_string($name)."\n";
    $email_message .= "Position: ".clean_string($position)."\n";
    $email_message .= "Email: ".clean_string($email_from)."\n";
    $email_message .= "Phone: ".clean_string($phone)."\n";
    $email_message .= "Comments: ".clean_string($comments)."\n";

    $allowedExts = array("doc", "docx", "xls", "xlsx", "pdf");
$temp = explode(".", $_FILES["file"]["name"]);
$extension = end($temp);
if ((($_FILES["file"]["type"] == "application/pdf")
|| ($_FILES["file"]["type"] == "application/msword")
|| ($_FILES["file"]["type"] == "application/excel")
|| ($_FILES["file"]["type"] == "application/vnd.ms-excel")
|| ($_FILES["file"]["type"] == "application/x-excel")
|| ($_FILES["file"]["type"] == "application/x-msexcel")
|| ($_FILES["file"]["type"] == "application/vnd.openxmlformats-officedocument.wordprocessingml.document")
|| ($_FILES["file"]["type"] == "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"))

&& in_array($extension, $allowedExts))
  {
  if ($_FILES["file"]["error"] > 0)
    {
    echo "<script>alert('Error: " . $_FILES["file"]["error"] ."')</script>";
    }
  else
    {
        $d='upload/';
        $de=$d . basename($_FILES['file']['name']);
    move_uploaded_file($_FILES["file"]["tmp_name"], $de);
$fileName = $_FILES['file']['name'];
    $filePath = $_FILES['file']['tmp_name'];
     //add only if the file is an upload
     }
  }
else
  {
  echo "<script>alert('Invalid file')</script>";
  }

// create email headers
$headers = 'From: '.$email_from."\r\n".
'Reply-To: '.$email_from."\r\n" .
'X-Mailer: PHP/' . phpversion();
//Create a new PHPMailer instance
$mail = new PHPMailer();
//Set who the message is to be sent from
$mail->SetFrom($email_from, $name);
//Set an alternative reply-to address
$mail->addReplyTo($email_from, $name);
//Set who the message is to be sent to
$mail->addAddress($email_to, $name_to);
//Set the subject line
$mail->Subject = $email_subject;
//Read an HTML message body from an external file, convert referenced images to embedded, convert HTML into a basic plain-text alternative body
$mail->MsgHTML($email_message);
//Replace the plain text body with one created manually
$mail->AltBody = $email_message;
//Attach an image file
$mail->AddAttachment($_FILES['file']['tmp_name'], $_FILES['file']['name']);
//Send the message, check for errors
if(!$mail->Send()) {
  echo "<script>alert('Mailer Error: " . $mail->ErrorInfo."')</script>";
} else {
  echo "<script>alert('Your request has been submitted. We will contact you soon.')</script>";
}
}
?>

Answer 1

As hackerone said, to change your code to send with SendGrid and PHPMailer, you'll need to update your code to include SMTP settings after instantiating PHPMailer. The following settings will work with SendGrid:

// This should go somewhere after $mail = new PHPMailer();
$mail->isSMTP();                                      // Set mailer to use SMTP
$mail->Host = 'smtp.sendgrid.net';                    // Specify server
$mail->SMTPAuth = true;                               // Enable SMTP authentication
$mail->Username = 'your_sendgrid_username';           // SMTP username
$mail->Password = 'your_sendgrid_password';           // SMTP password
$mail->Port = 587;                                    // Recommended Port
$mail->SMTPSecure = 'tls';                            // Enable encryption, 'ssl'

Answer 2

the following is code from phpmailer, you can specify the sendgrid smtp params after instantiating the PHPmailer.

$mail->isSMTP();                                      // Set mailer to use SMTP
$mail->Host = 'smtp1.example.com;smtp2.example.com';  // Specify main and backup server
$mail->SMTPAuth = true;                               // Enable SMTP authentication
$mail->Username = 'jswan';                            // SMTP username
$mail->Password = 'secret';                           // SMTP password
$mail->SMTPSecure = 'tls';                            // Enable encryption, 'ssl' also accepted