Serverless Plugin SNS Plus

A Serverless framework plugin to improve some of the pain points around SNS topics.

What is it?

The SNS Plus plugin manages SNS topics outside of the Serverless service's default Cloudformation stack. Topics are created on-demand, whenever they are referenced in serverless.yml.

Usage

Function Event

Subscribe a topic to an SNS Plus event, using similar syntax to the built-in sns event.

# serverless.yml
functions:
  myFunctionName:
    handler: someModule.handler
    events:
      - snsPlus: MyTopicName

This will do one of two things: 1. Create a topic if it doesn't already exist, then subscribe the Lambda function to it. 2. Subscribe to a topic that already exists.

Note: the topic is assumed to be in the same account/region where your service will be deployed. This may change something in the future.

Variable Syntax

# serverless.yml
functions:
  myFunctionName:
    handler: someModule.handler
    environment:
      MY_TOPIC: ${snsPlus:MyTopicName}

The `snsPlus` variable syntax accepts an SNS topic and does two things:
    1. Replaces the topic name with the full Arn of the SNS topic
    2. Creates the SNS topic before deployment if it does not already exist.

This is helpful if a function needs to publish as a part of its work, for example.