hawkapi-mail

Email plugin for HawkAPI. SMTP, AWS SES, SendGrid, Mailgun, Resend, Jinja2 templates, persistent outbox with retry, and webhook handlers for delivery/bounce/complaint events.

Install

pip install hawkapi-mail            # SMTP + SendGrid + Mailgun + Resend + outbox
pip install 'hawkapi-mail[ses]'     # adds AWS SES backend

Quickstart

from hawkapi import Depends, HawkAPI
from hawkapi_mail import (
    EmailMessage,
    Mailer,
    SMTPBackend,
    SMTPConfig,
    get_mailer,
    init_mail,
)

app = HawkAPI()
init_mail(
    app,
    backend=SMTPBackend(SMTPConfig(host="smtp.example.com", port=587, start_tls=True,
                                    username="api", password="secret")),
    default_sender="hello@example.com",
)


@app.post("/welcome")
async def welcome(email: str, mail: Mailer = Depends(get_mailer)):
    msg = EmailMessage.build(
        subject="Welcome!", to=email, text="Glad you joined.",
        html="<h1>Glad you joined.</h1>",
    )
    await mail.send(msg)
    return {"ok": True}

Backends

from hawkapi_mail import (
    InMemoryBackend,                                # tests
    SMTPBackend, SMTPConfig,                        # SMTP / SMTPS / STARTTLS
    SESBackend, SESConfig,                          # AWS SES (extras: [ses])
    SendGridBackend, SendGridConfig,                # SendGrid v3 API
    MailgunBackend, MailgunConfig,                  # Mailgun v3 API
    ResendBackend, ResendConfig,                    # Resend HTTP API
)

sendgrid = SendGridBackend(SendGridConfig(api_key="SG.xxx"))
mailgun  = MailgunBackend(MailgunConfig(api_key="key-xxx", domain="mg.example.com"))
resend   = ResendBackend(ResendConfig(api_key="re_xxx"))
ses      = SESBackend(SESConfig(region="eu-west-1"))   # uses boto3 / IAM

All backends share one async send(message) -> SendResult interface; swap them freely.

Templates

from hawkapi_mail import TemplateRenderer

templates = TemplateRenderer(directory="emails/")           # or package=..., or templates={...}
init_mail(app, backend=..., templates=templates, default_sender="hello@example.com")

await mail.send_template(
    "welcome.html",
    text_template="welcome.txt",
    context={"name": "Alice"},
    subject="Welcome",
    to="alice@example.com",
)

Jinja2 with async rendering + HTML autoescape on by default.

Persistent outbox

from hawkapi_mail import SQLiteOutbox, RetryPolicy

outbox = SQLiteOutbox(path="mail.db")
init_mail(
    app,
    backend=sendgrid,
    outbox=outbox,
    retry=RetryPolicy(max_attempts=5, base_seconds=5, max_seconds=3600),
    start_worker=True,     # drains the outbox in the background
)

# Enqueue instead of sending right away:
entry_id = await mail.send(message, deferred=True)

The worker pulls due entries, calls the backend, and on SendError schedules an exponential-backoff retry. After max_attempts the entry is dropped (logged at error level). For tests, swap in MemoryOutbox().

Webhooks

from hawkapi_mail import (
    verify_sendgrid, parse_sendgrid,
    verify_mailgun,  parse_mailgun,
    verify_resend,   parse_resend,
    parse_ses_sns,   confirm_ses_subscription,
)


@app.post("/webhooks/mailgun")
async def mailgun_hook(request):
    form = await request.form()
    verify_mailgun(
        signing_key="…",
        timestamp=form["timestamp"], token=form["token"], signature=form["signature"],
    )
    event = parse_mailgun(await request.body())
    # event.kind ∈ delivered | bounce | complaint | opened | clicked | unsubscribed | other
    return {"ok": True}


@app.post("/webhooks/ses")
async def ses_hook(request):
    body = await request.body()
    if await confirm_ses_subscription(body):       # SNS SubscriptionConfirmation
        return {"confirmed": True}
    for event in parse_ses_sns(body):
        ...
    return {"ok": True}

All providers normalize to a single WebhookEvent(provider, kind, recipient, message_id, timestamp, raw).

Testing

from hawkapi_mail import InMemoryBackend, init_mail

backend = InMemoryBackend()
init_mail(app, backend=backend, default_sender="me@x.com")

# After exercising the app:
assert len(backend.sent) == 1
assert backend.sent[0].subject == "Welcome"
backend.clear()

Development

git clone https://github.com/Hawk-API/hawkapi-mail.git
cd hawkapi-mail
uv sync --extra dev
uv run pytest -q
uv run ruff check . && uv run ruff format --check .
uv run pyright src/

License

MIT.