[javascript] How do I send email with JavaScript without opening the mail client?

I'm writing a HTML page with a registration button that should just silently send an email without opening the local mail client. Here is my HTML:

<form method="post" action="">
    <input type="text" id="email_address" name="name" placeholder="Enter your email address..." required>
    <button onclick="sendMail(); return false">Send Email</button>
</form>

... and here is my JavaScript code:

<script type="text/javascript">
  function sendMail() {
    var link = 'mailto:[email protected]?subject=Message from '
             +document.getElementById('email_address').value
             +'&body='+document.getElementById('email_address').value;
    window.location.href = link;
}
</script>

The code above works... but it opens the local email client. If I remove the return statement in the onclick attribute like this:

<form method="post" action="">
    <input type="text" id="email_address" name="name" placeholder="Enter your email address..." required>
    <button onclick="sendMail()">Send Email</button>
</form>

... then the email is not sent at all. Am I missing something?

Any help would be reeeally appreciated :-)

Directly From Client

Send an email using only JavaScript

in short: 
1. register for Mandrill to get an API key
2. load jQuery
3. use $.ajax to send an email

Like this -

function sendMail() {
    $.ajax({
      type: 'POST',
      url: 'https://mandrillapp.com/api/1.0/messages/send.json',
      data: {
        'key': 'YOUR API KEY HERE',
        'message': {
          'from_email': '[email protected]',
          'to': [
              {
                'email': '[email protected]',
                'name': 'RECIPIENT NAME (OPTIONAL)',
                'type': 'to'
              }
            ],
          'autotext': 'true',
          'subject': 'YOUR SUBJECT HERE!',
          'html': 'YOUR EMAIL CONTENT HERE! YOU CAN USE HTML!'
        }
      }
     }).done(function(response) {
       console.log(response); // if you're into that sorta thing
     });
}

https://medium.com/design-startups/b53319616782

Note: Keep in mind that your API key is visible to anyone, so any malicious user may use your key to send out emails that can eat up your quota.

Indirect via Your Server - secure

To overcome the above vulnerability, you can modify your own server to send the email after session based authentication.

node.js - https://www.npmjs.org/package/node-mandrill

var mandrill = require('node-mandrill')('<your API Key>'); 

function sendEmail ( _name, _email, _subject, _message) {
    mandrill('/messages/send', {
        message: {
            to: [{email: _email , name: _name}],
            from_email: '[email protected]',
            subject: _subject,
            text: _message
        }
    }, function(error, response){
        if (error) console.log( error );
        else console.log(response);
    });
}

// define your own email api which points to your server.

app.post( '/api/sendemail/', function(req, res){

    var _name = req.body.name;
    var _email = req.body.email;
    var _subject = req.body.subject;
    var _messsage = req.body.message;

    //implement your spam protection or checks. 

    sendEmail ( _name, _email, _subject, _message );

});

and then use use $.ajax on client to call your email API.

You need to do it directly on a server. But a better way is using PHP. I have heard that PHP has a special code that can send e-mail directly without opening the mail client.

You can't do it with client side script only... you could make an AJAX call to some server side code that will send an email...

You cannot cause the user's browser to send email silently. That would be a horrible security problem as any website could use their system as a spam relay and/or harvest their email address.

You need to make an HTTP request to a server side process (written in the language of your choice) which sends the mail from your server.

Well, PHP can do this easily.

It can be done with the PHP mail() function. Here's what a simple function would look like:

<?php     
$to_email = '[email protected]';
$subject = 'Testing PHP Mail';
$message = 'This mail is sent using the PHP mail function';
$headers = 'From: [email protected]';
mail($to_email,$subject,$message,$headers);
?>

This will send a background e-mail to the recipient specified in the $to_email.

The above example uses hard coded values in the source code for the email address and other details for simplicity.

Let’s assume you have to create a contact us form for users fill in the details and then submit.

1. Users can accidently or intentional inject code in the headers which can result in sending spam mail
2. To protect your system from such attacks, you can create a custom function that sanitizes and validates the values before the mail is sent.

Let’s create a custom function that validates and sanitizes the email address using the filter_var() built in function.

Here's an example code:

<?php 
function sanitize_my_email($field) {
    $field = filter_var($field, FILTER_SANITIZE_EMAIL);
    if (filter_var($field, FILTER_VALIDATE_EMAIL)) {
        return true;
    } else {
        return false;
    }
}
$to_email = '[email protected]';
$subject = 'Testing PHP Mail';
$message = 'This mail is sent using the PHP mail ';
$headers = 'From: [email protected]';
//check if the email address is invalid $secure_check
$secure_check = sanitize_my_email($to_email);
if ($secure_check == false) {
    echo "Invalid input";
} else { //send email 
    mail($to_email, $subject, $message, $headers);
    echo "This email is sent using PHP Mail";
}
?>

We will now let this be a separate PHP file, for example sendmail.php.

Then, will use this file on form submission, using the action attribute of the form, like:

<form action="sendmail.php" method="post">
   <input type="text" value="Your Name: ">
   <input type="password" value="Set Up A Passworrd">
   <input type="submit" value="Signup">
   <input type="reset" value="Reset Form">
</form>

Hope I could help

There needs to be some type of backend framework to send the email. This can be done via PHP/ASP.NET, or with the local mail client. If you want the user to see nothing, the best way is to tap into those by an AJAX call to a separate send_email file.

I think you can use smtpjs.com