Mailgun

Anymail integrates with the Mailgun transactional email service from Rackspace, using their REST API.

Settings

EMAIL_BACKEND

To use Anymail’s Mailgun backend, set:

EMAIL_BACKEND = "anymail.backends.mailgun.EmailBackend"

in your settings.py.

MAILGUN_API_KEY

Required. Your Mailgun API key:

ANYMAIL = {
    ...
    "MAILGUN_API_KEY": "<your API key>",
}

Anymail will also look for MAILGUN_API_KEY at the root of the settings file if neither ANYMAIL["MAILGUN_API_KEY"] nor ANYMAIL_MAILGUN_API_KEY is set.

MAILGUN_SENDER_DOMAIN

If you are using a specific Mailgun sender domain that is different from your messages’ from_email domains, set this to the domain you’ve configured in your Mailgun account.

If your messages’ from_email domains always match a configured Mailgun sender domain, this setting is not needed.

See Email sender domain below for examples.

MAILGUN_API_URL

The base url for calling the Mailgun API. It does not include the sender domain. (Anymail figures this out for you.)

The default is MAILGUN_API_URL = "https://api.mailgun.net/v3", which connects to Mailgun’s US service. You must override this if you are using Mailgun’s European region:

ANYMAIL = {
  "MAILGUN_API_KEY": "...",
  "MAILGUN_API_URL": "https://api.eu.mailgun.net/v3",
  # ...
}

Email sender domain

Mailgun’s API requires identifying the sender domain. By default, Anymail uses the domain of each messages’s from_email (e.g., “example.com” for “from@example.com”).

You will need to override this default if you are using a dedicated Mailgun sender domain that is different from a message’s from_email domain.

For example, if you are sending from “orders@example.com”, but your Mailgun account is configured for “mail1.example.com”, you should provide MAILGUN_SENDER_DOMAIN in your settings.py:

ANYMAIL = {
    ...
    "MAILGUN_API_KEY": "<your API key>",
    "MAILGUN_SENDER_DOMAIN": "mail1.example.com"
}

If you need to override the sender domain for an individual message, use Anymail’s envelope_sender (only the domain is used; anything before the @ is ignored):

message = EmailMessage(from_email="marketing@example.com", ...)
message.envelope_sender = "anything@mail2.example.com"  # the "anything@" is ignored

Changed in version 2.0: Earlier Anymail versions looked for a special sender_domain key in the message’s esp_extra to override Mailgun’s sender domain. This is still supported, but may be deprecated in a future release. Using envelope_sender as shown above is now preferred.

exp_extra support

Anymail’s Mailgun backend will pass all esp_extra values directly to Mailgun. You can use any of the (non-file) parameters listed in the Mailgun sending docs. Example:

message = AnymailMessage(...)
message.esp_extra = {
    'o:testmode': 'yes',  # use Mailgun's test mode
}

Limitations and quirks

Attachments require filenames

Mailgun has an undocumented API requirement that every attachment must have a filename. Attachments with missing filenames are silently dropped from the sent message. Similarly, every inline attachment must have a Content-ID.

To avoid unexpected behavior, Anymail will raise an AnymailUnsupportedFeature error if you attempt to send a message through Mailgun with any attachments that don’t have filenames (or inline attachments that don’t have Content-IDs).

Ensure your attachments have filenames by using message.attach_file(filename), message.attach(content, filename="..."), or if you are constructing your own MIME objects to attach, mimeobj.add_header("Content-Disposition", "attachment", filename="...").

Ensure your inline attachments have Content-IDs by using Anymail’s inline image helpers, or if you are constructing your own MIME objects, mimeobj.add_header("Content-ID", "...") and mimeobj.add_header("Content-Disposition", "inline").

Changed in version 4.3: Earlier Anymail releases did not check for these cases, and attachments without filenames/Content-IDs would be ignored by Mailgun without notice.

Envelope sender uses only domain
Anymail’s envelope_sender is used to select your Mailgun sender domain. For obvious reasons, only the domain portion applies. You can use anything before the @, and it will be ignored.

Batch sending/merge and ESP templates

Mailgun does not offer ESP stored templates, so Anymail’s template_id message attribute is not supported with the Mailgun backend.

Mailgun does support batch sending with per-recipient merge data. You can refer to Mailgun “recipient variables” in your message subject and body, and supply the values with Anymail’s normalized merge_data and merge_global_data message attributes:

message = EmailMessage(
    ...
    subject="Your order %recipient.order_no% has shipped",
    body="""Hi %recipient.name%,
            We shipped your order %recipient.order_no%
            on %recipient.ship_date%.""",
    to=["alice@example.com", "Bob <bob@example.com>"]
)
# (you'd probably also set a similar html body with %recipient.___% variables)
message.merge_data = {
    'alice@example.com': {'name': "Alice", 'order_no': "12345"},
    'bob@example.com': {'name': "Bob", 'order_no': "54321"},
}
message.merge_global_data = {
    'ship_date': "May 15"  # Anymail maps globals to all recipients
}

Mailgun does not natively support global merge data. Anymail emulates the capability by copying any merge_global_data values to each recipient’s section in Mailgun’s “recipient-variables” API parameter.

See the Mailgun batch sending docs for more information.

Status tracking webhooks

Changed in version 4.0: Added support for Mailgun’s June, 2018 (non-“legacy”) webhook format.

If you are using Anymail’s normalized status tracking, enter the url in the Mailgun webhooks dashboard. (Be sure to select the correct sending domain—Mailgun’s sandbox and production domains have separate webhook settings.)

Mailgun allows you to enter a different URL for each event type: just enter this same Anymail tracking URL for all events you want to receive:

https://random:random@yoursite.example.com/anymail/mailgun/tracking/

Mailgun implements a limited form of webhook signing, and Anymail will verify these signatures (based on your MAILGUN_API_KEY Anymail setting). By default, Mailgun’s webhook signature provides similar security to Anymail’s shared webhook secret, so it’s acceptable to omit the ANYMAIL_WEBHOOK_SECRET setting (and “{random}:{random}@” portion of the webhook url) with Mailgun webhooks.

Mailgun will report these Anymail event_types: delivered, rejected, bounced, complained, unsubscribed, opened, clicked.

The event’s esp_event field will be the parsed Mailgun webhook payload as a Python dict with "signature" and "event-data" keys.

Anymail uses Mailgun’s webhook token as its normalized event_id, rather than Mailgun’s event-data id (which is only guaranteed to be unique during a single day). If you need the event-data id, it can be accessed in your webhook handler as event.esp_event["event-data"]["id"]. (This can be helpful for working with Mailgun’s other event APIs.)

Note

Mailgun legacy webhooks

In late June, 2018, Mailgun introduced a new set of webhooks with an improved payload design, and at the same time renamed their original webhooks to “Legacy Webhooks.”

Anymail v4.0 and later supports both new and legacy Mailgun webhooks, and the same Anymail webhook url works as either. Earlier Anymail versions can only be used as legacy webhook urls.

The new (non-legacy) webhooks are preferred, particularly with Anymail’s metadata and tags features. But if you have already configured the legacy webhooks, there is no need to change.

If you are using Mailgun’s legacy webhooks:

  • The event.esp_event field will be a Django QueryDict of Mailgun event fields (the raw POST data provided by legacy webhooks).
  • You should avoid using “body-plain,” “h,” “message-headers,” “message-id” or “tag” as metadata keys. A design limitation in Mailgun’s legacy webhooks prevents Anymail from reliably retrieving this metadata from opened, clicked, and unsubscribed events. (This is not an issue with the newer, non-legacy webhooks.)

Inbound webhook

If you want to receive email from Mailgun through Anymail’s normalized inbound handling, follow Mailgun’s Receiving, Storing and Fowarding Messages guide to set up an inbound route that forwards to Anymail’s inbound webhook. (You can configure routes using Mailgun’s API, or simply using the Mailgun routes dashboard.)

The action for your route will be either:

forward("https://random:random@yoursite.example.com/anymail/mailgun/inbound/") forward("https://random:random@yoursite.example.com/anymail/mailgun/inbound_mime/")

Anymail accepts either of Mailgun’s “fully-parsed” (…/inbound/) and “raw MIME” (…/inbound_mime/) formats; the URL tells Mailgun which you want. Because Anymail handles parsing and normalizing the data, both are equally easy to use. The raw MIME option will give the most accurate representation of any received email (including complex forms like multi-message mailing list digests). The fully-parsed option may use less memory while processing messages with many large attachments.

If you want to use Anymail’s normalized spam_detected and spam_score attributes, you’ll need to set your Mailgun domain’s inbound spam filter to “Deliver spam, but add X-Mailgun-SFlag and X-Mailgun-SScore headers” (in the Mailgun domains dashboard).