Slide 39 - Sending Email § Session 13: Server-Side, Part 1

Sending Email

Mail service -- e.g. Mailgun, Sendgrid, etc.

submit.php Example (uses Mailgun)

<?php require_once 'vendor/autoload.php';

$loader = new \Twig\Loader\FilesystemLoader('./templates');
$twig = new \Twig\Environment($loader, [
    'cache' => './compilation_cache',
    'debug' => true,
    'auto_reload' => true
]);
$requestTime = new DateTime();
$requestTime->setTimestamp($_SERVER['REQUEST_TIME']);
$requestTimeHuman = $requestTime->format('Y-m-d\TH:i:s');

$echocontent = $twig->render('form-response-template.html',
     [
     'getparams' => $_GET,
     'postparams' => $_POST,
     'httpheaders' => getallheaders(),
     'httpmethod' => $_SERVER['REQUEST_METHOD'],
     'serverinfo' => $_SERVER,
     'requesttime' => $requestTimeHuman,
     'httpreferer' => $_SERVER['HTTP_REFERER']
     ]);
?>


<?php

require 'vendor/autoload.php';
use Mailgun\Mailgun;

$mailto = filter_var($_POST['__mailto'], FILTER_VALIDATE_EMAIL);
$mailkey = '';
if (preg_match('/^csci(e|s)12\-(spring|summer|fall)-\d{4}-[a-z]+[0-9]+$/',$_POST['__mailkey'])) {
   $mailkey = $_POST['__mailkey'];
}

// only send if POST and if __mailto and if __mailkey exist

if (strcmp($_SERVER['REQUEST_METHOD'],'POST') == 0 && $mailto && $mailkey ) {
  error_log("FormSubmit | MAILGUN | $mailkey | $mailto |");
  // First, instantiate the SDK with your API credentials
  $MG_API_KEY = getenv('MG_API_KEY');
  $MG_DOMAIN = getenv('MG_DOMAIN');
  $MG_FROM = getenv('MG_FROM');

  $mg = Mailgun::create($MG_API_KEY); // For US servers
  $domain = $MG_DOMAIN;

  // Now, compose and send your message.
  // $mg->messages()->send($domain, $params);
  $mg->messages()->send($domain, [
    'from'    => $MG_FROM,
    'to'      => $mailto,
    'subject' => 'Form Submission',
    'html'    => $echocontent
  ]);
}

echo($echocontent);
?>

form_response_template.html

This is a PHP "Twig" template.

<DOCTYPE html>
<html lang="en">
  <head><title>Form Submission</title>
    <style>
      body, * { font-family: helvetica, sans-serif; }
      body { margin: 1rem 5%; }
      h2 { margin-top: 1.5rem; }
      table, td, th, tr { border-collapse: collapse; }
      table td, table th { border-collapse: collapse; vertical-align: top; padding: 0.5rem; border: thin solid #101010; }
      table thead tr { color: #ffffff;  background-color: rgb(100,100,100); font-size: larger;}
      table tbody tr:nth-child(even) { background-color: rgb(240,240,240); }
      table tbody tr th { text-align: left; }
      footer { margin-top: 4rem; padding: 0.5rem; background-color: rgb(240,240,240); border-top: thin solid black; }
      footer p { margin-top: 0.5em; margin-bottom: 0.5em; }
    </style>
  </head>

  <body>
    <h1>Form Submission</h1>
    {% if getparams %}
    <h2>GET Parameters</h2>
    <table>
      <thead>
        <tr><th>Name</th><th>Value</th></tr>
      </thead>
      <tbody>
      {% for key, value in getparams %}
      <tr>
        <th>{{ key }}</th>
        <td>
          {% if value is iterable %}
          {% for v in value %}
            {{ v }}{% if not(loop.last) %},<br/>{% endif %}
          {% endfor %}
          {% else %}
            {{ value }}
          {% endif %}
        </td>
      </tr>
      {% endfor %}
      </tbody>
    </table>
    {% endif %}

    {% if postparams %}
    <h2>POST Parameters</h2>
    <table>
      <thead>
        <tr><th>Name</th><th>Value</th></tr>
      </thead>
      <tbody>
      {% for key, value in postparams %}
      <tr>
        <th>{{ key }}</th>
        <td>
          {% if value is iterable %}
          {% for v in value %}
            {{ v }}{% if not(loop.last) %},<br/>{% endif %}
          {% endfor %}
          {% else %}
            {{ value }}
          {% endif %}
        </td>
      </tr>
      {% endfor %}
      </tbody>
    </table>
    {% endif %}

    {% if serverinfo %}
    <h2>Request Information</h2>
    <table>
      <thead>
        <tr><th>Name</th><th>Value</th></tr>
      </thead>
      <tbody>
        <tr><th>Request Time</th><td>{{ requesttime }}</td></tr>
        <tr><th>Remote Address</th><td>{{ serverinfo['REMOTE_ADDR'] }}</td></tr>
        <tr><th>HTTP Referrer</th><td><a href="{{ httpreferer }}">{{ httpreferer }}</a></td></tr>
        <tr><th>HTTP Method</th><td>{{ httpmethod }}</td></tr>
      </tbody>
    </table>
    {% endif %}

    <footer>
      <p>This form submission tool is only for use by current students in <a href="https://cscie12.dce.harvard.edu/">CSCI E-12</a> and <a href="https://cscis12.dce.harvard.edu/">CSCI S-12</a> courses.</p><p>David Heitmeyer | <a href="https://extension.harvard.edu/">Harvard Extension School</a> | <a href="https://summer.harvard.edu/">Harvard Summer School</a></footer>
  </body>
 </html>