Email Notifications

If you remember from Creating Your Own service, we created a hello service with a hello() entrypoint that took a name and responded with a greeting:

import logging
from mvi.mvi import MviService, notify, Severity

mvi = MviService()
logger = logging.getLogger(__name__)

mvi.add_parameter("greeting_phrase", "Hello")


@mvi.entrypoint
def hello(name: str) -> str:
    greeting_phrase = mvi.get_parameter("greeting_phrase")
    if name == "World":
        notify(
            msg="Someone is trying to greet the World, too time consuming. Skipping!",
            severity=Severity.WARNING,
        )
        return "Greeting failed"
    logger.info(f"Greeting someone with the name: {name}")
    return f"{greeting_phrase} {name}"


mvi.run()

If the user tried to greet “World”, a notification would be raised, which could be viewed in the notification tab of the dashboard. In this tutorial we will see how that same notification can be sent as an email.

Manager Configuration

The first step is to set up an email address that the MVI Manager can use to send the notification emails. For this you need an SMTP server with an email account that you can use. We recommend to have a dedicated email address for sending MVI notifications.

The manager is configured with a notification sender email at startup. We do this by setting four different environment variables at manager startup

Environment Variable	Value
MVI_NOTIFICATION_SENDER_EMAIL	“email@address.com”
MVI_NOTIFICATION_SENDER_EMAIL_PASSWORD	“password”
MVI_NOTIFICATION_SMTP_SERVER	“smtp.server.url”
MVI_NOTIFICATION_SMTP_PORT	Usually 587 or 465

With the docker CLI:

>>> docker run -v /var/run/docker.sock:/var/run/docker.sock -p 80:80 -p 443:443 -e MVI_AUTH_ENABLED=True -e MVI_NOTIFICATION_SENDER_EMAIL="email@address.com" -e MVI_NOTIFICATION_SENDER_EMAIL_PASSWORD="password" -e MVI_NOTIFICATION_SMTP_SERVER="smtp.server.url" -e MVI_NOTIFICATION_SMTP_PORT=465 -d vikinganalyticsab/mvi_manager:latest

If everything worked, an email will be sent from “email@address.com” to itself, to show that it successfully connected. Otherwise, as long as the manager could still start, any issues with the email configuration will be viewable on the notification tab in the dashboard.

SDK Syntax

By default, notify() with not send any emails. For a notification to become an email notification, you have to pass a list of email addresses to the emails keyword argument of notify():

import logging
from mvi.mvi import MviService, notify, Severity

mvi = MviService()
logger = logging.getLogger(__name__)

mvi.add_parameter("greeting_phrase", "Hello")


@mvi.entrypoint
def hello(name: str) -> str:
    greeting_phrase = mvi.get_parameter("greeting_phrase")
    if name == "World":
        notify(
            msg="Someone is trying to greet the World, too time consuming. Skipping!",
            severity=Severity.WARNING,
            emails=["your@email.com"],
        )
        return "Greeting failed"
    logger.info(f"Greeting someone with the name: {name}")
    return f"{greeting_phrase} {name}"

To make the email recipients dynamically changeable, we can use this in conjunction with add_parameter() like so:

import logging
from mvi.mvi import MviService, notify, Severity

mvi = MviService()
logger = logging.getLogger(__name__)

mvi.add_parameter("greeting_phrase", "Hello")
mvi.add_parameter("emails", ["your@email.com"])


@mvi.entrypoint
def hello(name: str) -> str:
    greeting_phrase = mvi.get_parameter("greeting_phrase")
    emails = mvi.get_parameter("emails")
    if name == "World":
        notify(
            msg="Someone is trying to greet the World, too time consuming. Skipping!",
            severity=Severity.WARNING,
            emails=emails,
        )
        return "Greeting failed"
    logger.info(f"Greeting someone with the name: {name}")
    return f"{greeting_phrase} {name}"

This way, email addresses can be added and removed. You could of course use different emails for different notifications, so different stakeholders get notified of different things.