Send SMS from an Airflow DAG using AWS SNS

This article is a part of my "100 data engineering tutorials in 100 days" challenge. (97/100)

In this article, I am going to show you how to use Terraform to create and configure an SNS topic that delivers SMS messages to a mobile phone number. In the second part, I will use the SnsPublishOperator to send messages from Airflow.

Define an SNS topic and subscription

First, we have to define a new aws_sns_topic resource in Terraform:

1
2
3
resource "aws_sns_topic" "send-sms" {
    name = "send-sms"
}

After that, we have to add each recipient as a new SNS topic subscription:

1
2
3
4
5
resource "aws_sns_topic_subscription" "send-sms-recipient" {
    topic_arn = aws_sns_topic.send-sms.arn
    protocol = "sms"
    endpoint = "phone number with country code"
}

In the end, we have to define an access policy that allows publishing messages:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
data "aws_iam_policy_document" "sns_topic_policy" {
  policy_id = "__default_policy_ID"

  statement {
    actions = [
      "SNS:Publish"
    ]

    effect = "Allow"

    principals {
      type        = "AWS"
      identifiers = ["aws_identifier_of_the_AWS_user_used_by_Airflow"]
    }

    resources = [
      aws_sns_topic.send-sms.arn,
    ]

    sid = "__default_statement_ID"
  }
}

Sending SMS message from Airflow

To send a text message, we have to call the SnsPublishOperator inside an Airflow DAG. Of course, we can use templates to pass values to the message:

1
2
3
4
5
6
7
8
from airflow.contrib.operators.sns_publish_operator import SnsPublishOperator

send_sms = SnsPublishOperator(
    task_id='send_sms',
    target_arn='sns_topic_arn',
    message='Here is the message. You can use the template variables to get values from XCom or DAG parameters.',
    aws_conn_id='aws_connection_id'
)

Did you enjoy reading this article?
Would you like to learn more about software craft in data engineering and MLOps?

Subscribe to the newsletter or add this blog to your RSS reader (does anyone still use them?) to get a notification when I publish a new essay!

Newsletter

Do you enjoy reading my articles?
Subscribe to the newsletter if you don't want to miss the new content, business offers, and free training materials.

Bartosz Mikulski

Bartosz Mikulski

  • Data/MLOps engineer by day
  • DevRel/copywriter by night
  • Python and data engineering trainer
  • Conference speaker
  • Contributed a chapter to the book "97 Things Every Data Engineer Should Know"
  • Twitter: @mikulskibartosz
Newsletter

Do you enjoy reading my articles?
Subscribe to the newsletter if you don't want to miss the new content, business offers, and free training materials.