function drupal_mail

Composes and optionally sends an e-mail message.

Sending an e-mail works with defining an e-mail template (subject, text and possibly e-mail headers) and the replacement values to use in the appropriate places in the template. Processed e-mail templates are requested from hook_mail() from the module sending the e-mail. Any module can modify the composed e-mail message array using hook_mail_alter(). Finally drupal_mail_system()->mail() sends the e-mail, which can be reused if the exact same composed e-mail is to be sent to multiple recipients.

Finding out what language to send the e-mail with needs some consideration. If you send e-mail to a user, her preferred language should be fine, so use user_preferred_language(). If you send email based on form values filled on the page, there are two additional choices if you are not sending the e-mail to a user on the site. You can either use the language used to generate the page ($language global variable) or the site default language. See language_default(). The former is good if sending e-mail to the person filling the form, the later is good if you send e-mail to an address previously set up (like contact addresses in a contact form).

Taking care of always using the proper language is even more important when sending e-mails in a row to multiple users. Hook_mail() abstracts whether the mail text comes from an administrator setting or is static in the source code. It should also deal with common mail tokens, only receiving $params which are unique to the actual e-mail at hand.

An example:

function example_notify($accounts) {
  foreach ($accounts as $account) {
    $params['account'] = $account;

    // example_mail() will be called based on the first drupal_mail() parameter.
    drupal_mail('example', 'notice', $account->mail, user_preferred_language($account), $params);
function example_mail($key, &$message, $params) {
  $data['user'] = $params['account'];
  $options['language'] = $message['language'];
  user_mail_tokens($variables, $data, $options);
  switch ($key) {
    case 'notice':

      // If the recipient can receive such notices by instant-message, do
      // not send by email.
      if (example_im_send($key, $message, $params)) {
        $message['send'] = FALSE;
      $langcode = $message['language']->language;
      $message['subject'] = t('Notification from !site', $variables, array(
        'langcode' => $langcode,
      $message['body'][] = t("Dear !username\n\nThere is new content available on the site.", $variables, array(
        'langcode' => $langcode,

Another example, which uses drupal_mail() to format a message for sending later:

$params = array(
  'current_conditions' => $data,
$to = '';
$message = drupal_mail('example', 'notice', $to, $language, $params, FALSE);

// Only add to the spool if sending was not canceled.
if ($message['send']) {


$module: A module name to invoke hook_mail() on. The {$module}_mail() hook will be called to complete the $message structure which will already contain common defaults.

$key: A key to identify the e-mail sent. The final e-mail id for e-mail altering will be {$module}_{$key}.

$to: The e-mail address or addresses where the message will be sent to. The formatting of this string will be validated with the PHP e-mail validation filter. Some examples are:

$language: Language object to use to compose the e-mail.

$params: Optional parameters to build the e-mail.

$from: Sets From to this value, if given.

$send: If TRUE, drupal_mail() will call drupal_mail_system()->mail() to deliver the message, and store the result in $message['result']. Modules implementing hook_mail_alter() may cancel sending by setting $message['send'] to FALSE.

Return value

The $message array structure containing all details of the message. If already sent ($send = TRUE), then the 'result' element will contain the success indicator of the e-mail, failure being already written to the watchdog. (Success means nothing more than the message being accepted at php-level, which still doesn't guarantee it to be delivered.)

8 calls to drupal_mail()
contact_personal_form_submit in drupal/modules/contact/
Form submission handler for contact_personal_form().
contact_site_form_submit in drupal/modules/contact/
Form submission handler for contact_site_form().
hook_watchdog in drupal/modules/system/system.api.php
Log an event message.
MailTestCase::testCancelMessage in drupal/modules/simpletest/tests/mail.test
Test that message sending may be canceled.
MailTestCase::testPluggableFramework in drupal/modules/simpletest/tests/mail.test
Assert that the pluggable mail system is functional.

... See full list


drupal/includes/, line 122
API functions for processing and sending e-mail.


function drupal_mail($module, $key, $to, $language, $params = array(), $from = NULL, $send = TRUE) {
  $default_from = variable_get('site_mail', ini_get('sendmail_from'));

  // Bundle up the variables into a structured array for altering.
  $message = array(
    'id' => $module . '_' . $key,
    'module' => $module,
    'key' => $key,
    'to' => $to,
    'from' => isset($from) ? $from : $default_from,
    'language' => $language,
    'params' => $params,
    'send' => TRUE,
    'subject' => '',
    'body' => array(),

  // Build the default headers
  $headers = array(
    'MIME-Version' => '1.0',
    'Content-Type' => 'text/plain; charset=UTF-8; format=flowed; delsp=yes',
    'Content-Transfer-Encoding' => '8Bit',
    'X-Mailer' => 'Drupal',
  if ($default_from) {

    // To prevent e-mail from looking like spam, the addresses in the Sender and
    // Return-Path headers should have a domain authorized to use the originating
    // SMTP server.
    $headers['From'] = $headers['Sender'] = $headers['Return-Path'] = $default_from;
  if ($from) {
    $headers['From'] = $from;
  $message['headers'] = $headers;

  // Build the e-mail (get subject and body, allow additional headers) by
  // invoking hook_mail() on this module. We cannot use module_invoke() as
  // we need to have $message by reference in hook_mail().
  if (function_exists($function = $module . '_mail')) {
    $function($key, $message, $params);

  // Invoke hook_mail_alter() to allow all modules to alter the resulting e-mail.
  drupal_alter('mail', $message);

  // Retrieve the responsible implementation for this message.
  $system = drupal_mail_system($module, $key);

  // Format the message body.
  $message = $system

  // Optionally send e-mail.
  if ($send) {

    // The original caller requested sending. Sending was canceled by one or
    // more hook_mail_alter() implementations. We set 'result' to NULL, because
    // FALSE indicates an error in sending.
    if (empty($message['send'])) {
      $message['result'] = NULL;
    else {
      $message['result'] = $system

      // Log errors.
      if (!$message['result']) {
        watchdog('mail', 'Error sending e-mail (from %from to %to).', array(
          '%from' => $message['from'],
          '%to' => $message['to'],
        ), WATCHDOG_ERROR);
        drupal_set_message(t('Unable to send e-mail. Contact the site administrator if the problem persists.'), 'error');
  return $message;