How to Create an Amazon SNS Topic with PowerShell

Let's say that you have a highly automated AWS infrastructure. How do you receive notifications for changes or issues in that infrastructure? You might use AWS SNS to handle sending those notifications. Your environment is automated, so you can't pre-configure SNS. You need to automate that process, too. So, you need to learn how to automate AWS SNS. One of the goals of automating SNS is being able to create new Topics via scripts.

To do that, you need to learn how to create an Amazon SNS topic with PowerShell. In this article, we are going to discuss exactly that. We will explain what an SNS topic is and how you create an SNS topic with PowerShell.

What is the Difference Between Imperative and Declarative Calls to AWS SNS?

AWS has a lot of tools for cloud engineers. One of those tools is Cloud Formation. Cloud Formation lets organizations define specific rules and configurations for AWS services. Of course, this is a super simplified way of explaining Cloud Formation. But, think of Cloud Formation as a recipe and rule book for AWS.

One of the things that Cloud Formation can do is predefine how AWS SNS is handled. Businesses need to create these definitions ahead of time, though, per their business requirements.

When you create an SNS topic in AWS through Cloud Formation, you are using a declarative approach. Otherwise, everything is already declared or defined for you. However, using an imperative approach, you need to define all the rules for an SNS topic when creating it.

Though this explanation might be over-simplified, that is the difference between using an imperative and declarative approach. It's essentially when and where you define parameters for AWS SNS.

What is an AWS SNS Topic?

According to Amazon, an SNS topic is "… a logical access point that acts as a communication channel." What does that even mean, though?

Let's talk about what Amazon SNS does so we can understand that.

SNS is a tool that makes sending messages via email, text message, etc… easy. It's meant to hook in with other AWS services. For example, let's say that you have a bunch of EC2 instances running. If one of those EC2 instances has an issue, how will you know? AWS Cloud Watch can monitor your EC2 instances, and when Cloud Watch sees a problem, it can trigger SNS to send you an email warning you that one of your EC2 instances has an issue. That way, you are notified immediately.

How does SNS know where to send that message to, though? That's what a topic is for.

An SNS topic is essentially a label for a group of places to send messages. Technically, it's a label for a group of endpoints. Those endpoints can be HTTPS addresses for a REST service, an email address, or a place to send a text message.

Let's say that you have multiple EC2 instances that power different parts of your website. You also have developers and IT admins that are responsible for individual parts of that website's infrastructure. Obviously, you don't want to notify everyone if any issues occur with those EC2 instances. You only want to inform the people that matter.

This is why it's helpful to create different SNS topics. By using Cloud Watch, you can control who is notified of specific issues. Of course, you don't need to use Cloud Watch to also use SNS. SNS can be used in lots of different ways. This is only one example.

How to Create an Amazon SNS Topic with PowerShell

Creating an Amazon SNS Topic with PowerShell is a straightforward process. Still, you need to make sure PowerShell is ready to work with AWS first. To do that, you need to install the AWS Tools for PowerShell package.

The AWS Tools for PowerShell package comes in two flavors. The AWS Tools package is a bunch of applets combined. So, you do have the option of only installing the specific pieces of the AWS Tools for PowerShell package that you need. You can also install the core package that includes all the applets for working with the AWS SDK. Both can be installed from the PowerShell gallery provided by Microsoft.

After the AWS Tools for PowerShell package is installed, don't forget to configure your AWS Credentials in it. This is required before working with the AWS SDK in PowerShell.

Installing and configuring the AWS Tools for PowerShell package is beyond the scope of this article. However, it is recommended that you visit the AWS documentation page for PowerShell if you need assistance with these steps.

Creating a new SNS topic in PowerShell is as easy as using the applet command below: