Sending email | Django documentation (original) (raw)

Although Python provides a mail sending interface via the smtplibmodule, Django provides a couple of light wrappers over it. These wrappers are provided to make sending email extra quick, to help test email sending during development, and to provide support for platforms that can’t use SMTP.

The code lives in the django.core.mail module.

Quick examples

Use send_mail() for straightforward email sending. For example, to send a plain text message:

from django.core.mail import send_mail

send_mail( "Subject here", "Here is the message.", "from@example.com", ["to@example.com"], fail_silently=False, )

When additional email sending functionality is needed, useEmailMessage or EmailMultiAlternatives. For example, to send a multipart email that includes both HTML and plain text versions with a specific template and custom headers, you can use the following approach:

from django.core.mail import EmailMultiAlternatives from django.template.loader import render_to_string

First, render the plain text content.

text_content = render_to_string( "templates/emails/my_email.txt", context={"my_variable": 42}, )

Secondly, render the HTML content.

html_content = render_to_string( "templates/emails/my_email.html", context={"my_variable": 42}, )

Then, create a multipart email instance.

msg = EmailMultiAlternatives( "Subject here", text_content, "from@example.com", ["to@example.com"], headers={"List-Unsubscribe": "mailto:unsub@example.com"}, )

Lastly, attach the HTML content to the email instance and send.

msg.attach_alternative(html_content, "text/html") msg.send()

Mail is sent using the SMTP host and port specified in theEMAIL_HOST and EMAIL_PORT settings. TheEMAIL_HOST_USER and EMAIL_HOST_PASSWORD settings, if set, are used to authenticate to the SMTP server, and theEMAIL_USE_TLS and EMAIL_USE_SSL settings control whether a secure connection is used.

Note

The character set of email sent with django.core.mail will be set to the value of your DEFAULT_CHARSET setting.

send_mail()

send_mail(subject, message, from_email, recipient_list, fail_silently=False, auth_user=None, auth_password=None, connection=None, html_message=None)[source]

In most cases, you can send email using django.core.mail.send_mail().

The subject, message, from_email and recipient_list parameters are required.

The return value will be the number of successfully delivered messages (which can be 0 or 1 since it can only send one message).

send_mass_mail()

send_mass_mail(datatuple, fail_silently=False, auth_user=None, auth_password=None, connection=None)[source]

django.core.mail.send_mass_mail() is intended to handle mass emailing.

datatuple is a tuple in which each element is in this format:

(subject, message, from_email, recipient_list)

fail_silently, auth_user and auth_password have the same functions as in send_mail().

Each separate element of datatuple results in a separate email message. As in send_mail(), recipients in the samerecipient_list will all see the other addresses in the email messages’ “To:” field.

For example, the following code would send two different messages to two different sets of recipients; however, only one connection to the mail server would be opened:

message1 = ( "Subject here", "Here is the message", "from@example.com", ["first@example.com", "other@example.com"], ) message2 = ( "Another Subject", "Here is another message", "from@example.com", ["second@test.com"], ) send_mass_mail((message1, message2), fail_silently=False)

The return value will be the number of successfully delivered messages.

send_mass_mail() vs. send_mail()

The main difference between send_mass_mail() andsend_mail() is thatsend_mail() opens a connection to the mail server each time it’s executed, while send_mass_mail() uses a single connection for all of its messages. This makessend_mass_mail() slightly more efficient.

mail_admins()

mail_admins(subject, message, fail_silently=False, connection=None, html_message=None)[source]

django.core.mail.mail_admins() is a shortcut for sending an email to the site admins, as defined in the ADMINS setting.

mail_admins() prefixes the subject with the value of theEMAIL_SUBJECT_PREFIX setting, which is "[Django] " by default.

The “From:” header of the email will be the value of theSERVER_EMAIL setting.

This method exists for convenience and readability.

If html_message is provided, the resulting email will be a_multipart/alternative_ email with message as the_text/plain_ content type and html_message as the_text/html_ content type.

mail_managers()

mail_managers(subject, message, fail_silently=False, connection=None, html_message=None)[source]

django.core.mail.mail_managers() is just like mail_admins(), except it sends an email to the site managers, as defined in the MANAGERSsetting.

Examples

This sends a single email to john@example.com and jane@example.com, with them both appearing in the “To:”:

send_mail( "Subject", "Message.", "from@example.com", ["john@example.com", "jane@example.com"], )

This sends a message to john@example.com and jane@example.com, with them both receiving a separate email:

datatuple = ( ("Subject", "Message.", "from@example.com", ["john@example.com"]), ("Subject", "Message.", "from@example.com", ["jane@example.com"]), ) send_mass_mail(datatuple)

Preventing header injection

Header injection is a security exploit in which an attacker inserts extra email headers to control the “To:” and “From:” in email messages that your scripts generate.

The Django email functions outlined above all protect against header injection by forbidding newlines in header values. If any subject, from_email orrecipient_list contains a newline (in either Unix, Windows or Mac style), the email function (e.g. send_mail()) will raisedjango.core.mail.BadHeaderError (a subclass of ValueError) and, hence, will not send the email. It’s your responsibility to validate all data before passing it to the email functions.

If a message contains headers at the start of the string, the headers will be printed as the first bit of the email message.

Here’s an example view that takes a subject, message and from_emailfrom the request’s POST data, sends that to admin@example.com and redirects to “/contact/thanks/” when it’s done:

from django.core.mail import BadHeaderError, send_mail from django.http import HttpResponse, HttpResponseRedirect

def send_email(request): subject = request.POST.get("subject", "") message = request.POST.get("message", "") from_email = request.POST.get("from_email", "") if subject and message and from_email: try: send_mail(subject, message, from_email, ["admin@example.com"]) except BadHeaderError: return HttpResponse("Invalid header found.") return HttpResponseRedirect("/contact/thanks/") else: # In reality we'd use a form class # to get proper validation errors. return HttpResponse("Make sure all fields are entered and valid.")

The EmailMessage class

Django’s send_mail() andsend_mass_mail() functions are actually thin wrappers that make use of the EmailMessage class.

Not all features of the EmailMessage class are available through the send_mail() and related wrapper functions. If you wish to use advanced features, such as BCC’ed recipients, file attachments, or multi-part email, you’ll need to createEmailMessage instances directly.

Note

This is a design feature. send_mail() and related functions were originally the only interface Django provided. However, the list of parameters they accepted was slowly growing over time. It made sense to move to a more object-oriented design for email messages and retain the original functions only for backwards compatibility.

EmailMessage is responsible for creating the email message itself. The email backend is then responsible for sending the email.

For convenience, EmailMessage provides a send()method for sending a single email. If you need to send multiple messages, the email backend API provides an alternative.

EmailMessage Objects

class EmailMessage[source]

The EmailMessage class is initialized with the following parameters (in the given order, if positional arguments are used). All parameters are optional and can be set at any time prior to calling thesend() method.

For example:

from django.core.mail import EmailMessage

email = EmailMessage( "Hello", "Body goes here", "from@example.com", ["to1@example.com", "to2@example.com"], ["bcc@example.com"], reply_to=["another@example.com"], headers={"Message-ID": "foo"}, )

The class has the following methods:

class EmailAttachment

New in Django 5.2.

A named tuple to store attachments to an email.

The named tuple has the following indexes:

Sending alternative content types

Sending multiple content versions

It can be useful to include multiple versions of the content in an email; the classic example is to send both text and HTML versions of a message. With Django’s email library, you can do this using theEmailMultiAlternatives class.

class EmailMultiAlternatives[source]

A subclass of EmailMessage that allows additional versions of the message body in the email via the attach_alternative() method. This directly inherits all methods (including the class initialization) fromEmailMessage.

alternatives

A list of EmailAlternative named tuples. This is particularly useful in tests:

self.assertEqual(len(msg.alternatives), 1) self.assertEqual(msg.alternatives[0].content, html_content) self.assertEqual(msg.alternatives[0].mimetype, "text/html")

Alternatives should only be added using the attach_alternative()method, or passed to the constructor.

Changed in Django 5.2:

In older versions, alternatives was a list of regular tuples, as opposed to EmailAlternative named tuples.

attach_alternative(content, mimetype)[source]

Attach an alternative representation of the message body in the email.

For example, to send a text and HTML combination, you could write:

from django.core.mail import EmailMultiAlternatives

subject = "hello" from_email = "from@example.com" to = "to@example.com" text_content = "This is an important message." html_content = "

This is an important message.

" msg = EmailMultiAlternatives(subject, text_content, from_email, [to]) msg.attach_alternative(html_content, "text/html") msg.send()

body_contains(text)[source]

New in Django 5.2.

Returns a boolean indicating whether the provided text is contained in the email body and in all attached MIME typetext/* alternatives.

This can be useful when testing emails. For example:

def test_contains_email_content(self): subject = "Hello World" from_email = "from@example.com" to = "to@example.com" msg = EmailMultiAlternatives(subject, "I am content.", from_email, [to]) msg.attach_alternative("

I am content.

", "text/html")

self.assertIs(msg.body_contains("I am content"), True)
self.assertIs(msg.body_contains("<p>I am content.</p>"), False)

class EmailAlternative

New in Django 5.2.

A named tuple to store alternative versions of email content.

The named tuple has the following indexes:

Updating the default content type

By default, the MIME type of the body parameter in anEmailMessage is "text/plain". It is good practice to leave this alone, because it guarantees that any recipient will be able to read the email, regardless of their mail client. However, if you are confident that your recipients can handle an alternative content type, you can use the content_subtype attribute on theEmailMessage class to change the main content type. The major type will always be "text", but you can change the subtype. For example:

msg = EmailMessage(subject, html_content, from_email, [to]) msg.content_subtype = "html" # Main content is now text/html msg.send()

Email backends

The actual sending of an email is handled by the email backend.

The email backend class has the following methods:

It can also be used as a context manager, which will automatically callopen() and close() as needed:

from django.core import mail

with mail.get_connection() as connection: mail.EmailMessage( subject1, body1, from1, [to1], connection=connection, ).send() mail.EmailMessage( subject2, body2, from2, [to2], connection=connection, ).send()

Obtaining an instance of an email backend

The get_connection() function in django.core.mail returns an instance of the email backend that you can use.

get_connection(backend=None, fail_silently=False, *args, **kwargs)[source]

By default, a call to get_connection() will return an instance of the email backend specified in EMAIL_BACKEND. If you specify thebackend argument, an instance of that backend will be instantiated.

The fail_silently argument controls how the backend should handle errors. If fail_silently is True, exceptions during the email sending process will be silently ignored.

All other arguments are passed directly to the constructor of the email backend.

Django ships with several email sending backends. With the exception of the SMTP backend (which is the default), these backends are only useful during testing and development. If you have special email sending requirements, you can write your own email backend.

SMTP backend

class backends.smtp.EmailBackend(host=None, port=None, username=None, password=None, use_tls=None, fail_silently=False, use_ssl=None, timeout=None, ssl_keyfile=None, ssl_certfile=None, **kwargs)

This is the default backend. Email will be sent through a SMTP server.

The value for each argument is retrieved from the matching setting if the argument is None:

The SMTP backend is the default configuration inherited by Django. If you want to specify it explicitly, put the following in your settings:

EMAIL_BACKEND = "django.core.mail.backends.smtp.EmailBackend"

If unspecified, the default timeout will be the one provided bysocket.getdefaulttimeout(), which defaults to None (no timeout).

Console backend

Instead of sending out real emails the console backend just writes the emails that would be sent to the standard output. By default, the console backend writes to stdout. You can use a different stream-like object by providing the stream keyword argument when constructing the connection.

To specify this backend, put the following in your settings:

EMAIL_BACKEND = "django.core.mail.backends.console.EmailBackend"

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

File backend

The file backend writes emails to a file. A new file is created for each new session that is opened on this backend. The directory to which the files are written is either taken from the EMAIL_FILE_PATH setting or from the file_path keyword when creating a connection withget_connection().

To specify this backend, put the following in your settings:

EMAIL_BACKEND = "django.core.mail.backends.filebased.EmailBackend" EMAIL_FILE_PATH = "/tmp/app-messages" # change this to a proper location

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

In-memory backend

The 'locmem' backend stores messages in a special attribute of thedjango.core.mail module. The outbox attribute is created when the first message is sent. It’s a list with anEmailMessage instance for each message that would be sent.

To specify this backend, put the following in your settings:

EMAIL_BACKEND = "django.core.mail.backends.locmem.EmailBackend"

This backend is not intended for use in production – it is provided as a convenience that can be used during development and testing.

Django’s test runner automatically uses this backend for testing.

Dummy backend

As the name suggests the dummy backend does nothing with your messages. To specify this backend, put the following in your settings:

EMAIL_BACKEND = "django.core.mail.backends.dummy.EmailBackend"

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

Defining a custom email backend

If you need to change how emails are sent you can write your own email backend. The EMAIL_BACKEND setting in your settings file is then the Python import path for your backend class.

Custom email backends should subclass BaseEmailBackend that is located in the django.core.mail.backends.base module. A custom email backend must implement the send_messages(email_messages) method. This method receives a list of EmailMessage instances and returns the number of successfully delivered messages. If your backend has any concept of a persistent session or connection, you should also implement the open()and close() methods. Refer to smtp.EmailBackend for a reference implementation.

Sending multiple emails

Establishing and closing an SMTP connection (or any other network connection, for that matter) is an expensive process. If you have a lot of emails to send, it makes sense to reuse an SMTP connection, rather than creating and destroying a connection every time you want to send an email.

There are two ways you tell an email backend to reuse a connection.

Firstly, you can use the send_messages() method on a connection. This takes a list of EmailMessage (or subclass) instances, and sends them all using that single connection. As a consequence, any connection set on an individual message is ignored.

For example, if you have a function called get_notification_email() that returns a list of EmailMessage objects representing some periodic email you wish to send out, you could send these emails using a single call to send_messages:

from django.core import mail

connection = mail.get_connection() # Use default email connection messages = get_notification_email() connection.send_messages(messages)

In this example, the call to send_messages() opens a connection on the backend, sends the list of messages, and then closes the connection again.

The second approach is to use the open() and close() methods on the email backend to manually control the connection. send_messages() will not manually open or close the connection if it is already open, so if you manually open the connection, you can control when it is closed. For example:

from django.core import mail

connection = mail.get_connection()

Manually open the connection

connection.open()

Construct an email message that uses the connection

email1 = mail.EmailMessage( "Hello", "Body goes here", "from@example.com", ["to1@example.com"], connection=connection, ) email1.send() # Send the email

Construct two more messages

email2 = mail.EmailMessage( "Hello", "Body goes here", "from@example.com", ["to2@example.com"], ) email3 = mail.EmailMessage( "Hello", "Body goes here", "from@example.com", ["to3@example.com"], )

Send the two emails in a single call -

connection.send_messages([email2, email3])

The connection was already open so send_messages() doesn't close it.

We need to manually close the connection.

connection.close()

Configuring email for development

There are times when you do not want Django to send emails at all. For example, while developing a website, you probably don’t want to send out thousands of emails – but you may want to validate that emails will be sent to the right people under the right conditions, and that those emails will contain the correct content.

The easiest way to configure email for local development is to use theconsole email backend. This backend redirects all email to stdout, allowing you to inspect the content of mail.

The file email backend can also be useful during development – this backend dumps the contents of every SMTP connection to a file that can be inspected at your leisure.

Another approach is to use a “dumb” SMTP server that receives the emails locally and displays them to the terminal, but does not actually send anything. The aiosmtpd package provides a way to accomplish this:

python -m pip install aiosmtpd

python -m aiosmtpd -n -l localhost:8025

This command will start a minimal SMTP server listening on port 8025 of localhost. This server prints to standard output all email headers and the email body. You then only need to set the EMAIL_HOST andEMAIL_PORT accordingly. For a more detailed discussion of SMTP server options, see the documentation of the aiosmtpd module.

For information about unit-testing the sending of emails in your application, see the Email services section of the testing documentation.