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;
                break;
            }
            $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,
            ));
            break;
    }
}

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

$params = array(
    'current_conditions' => $data,
);
$to = 'user@example.com';
$message = drupal_mail('example', 'notice', $to, $language, $params, FALSE);
// Only add to the spool if sending was not canceled.
if ($message['send']) {
    example_spool_message($message);
}

Parameters

$module: A module name to invoke hook_mail() on. The {$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.)

10 calls to drupal_mail()
contact_personal_form_submit in modules/contact/contact.pages.inc
Form submission handler for contact_personal_form().
contact_site_form_submit in modules/contact/contact.pages.inc
Form submission handler for contact_site_form().
hook_watchdog in modules/system/system.api.php
Log an event message.
MailTestCase::testCancelMessage in modules/simpletest/tests/mail.test
Test that message sending may be canceled.
MailTestCase::testFromHeader in modules/simpletest/tests/mail.test
Checks for the site name in an auto-generated From: header.

... See full list

File

includes/mail.inc, line 128

Code

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 (variable_get('mail_display_name_site_name', FALSE)) {
            $display_name = variable_get('site_name', 'Drupal');
            $headers['From'] = drupal_mail_format_display_name($display_name) . ' <' . $default_from . '>';
        }
    }
    if ($from && $from != $default_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 = $system->format($message);
    // 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'] = $system->mail($message);
            // 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;
}

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