README.md

Step Functions with SNS

Starting the execution of the Step Function State Machine via AWS Console to call the SNS Publish API from a Task state. The State Machine accepts values in a JSON format (please see sample payload) and will execute the SNS Publish API to send a message to the configured SNS Topic.

State Machine Definition

{
  "StartAt": "step-function-definition",
  "States": {
    "step-function-definition": {
      "End": true,
      "Type": "Task",
      "ResultPath": null,
      "Resource": "arn:aws:states:::sns:publish",
      "Parameters": {
        "TopicArn": "arn:aws:sns:us-east-1:123456789101:step-function-topic",
        "Message.$": "$.content",
        "Subject.$": "$.subject"
      }
    }
  }
}

Sample Payload

{
  "subject": "Alert #17052023FB0508",
  "content": "Hello John,\n\nWe regret to inform you that your application, XYZ, encountered an error. The error message is as follows:\n\n\tAn unexpected error occurred while processing your request. Please take note of the following details for troubleshooting:\n\t\tError Message: Invalid input format for parameter 'transaction'. Expected a string value.\n\t\tRequest ID: 79dcbfaa-123b-40c2-b632-1110a21a6063\n\t\tTimestamp: 2023-05-17 10:15:23 UTC\n\nIf you have any questions or concerns, please contact our support team at [email protected]."
}

Sample SNS Email

AWS CDK API / Developer Reference

• AWS Step Functions
• Amazon CloudWatch Logs
• Tasks for Steps Functions
• Amazon Simple Notification Service

AWS Documentation Developer Guide

• States
• Amazon States Language
• AWS Step Function Guides
• Service Integration Patterns
• Call Amazon SNS with Step Functions
• Input and Output Processing in Step Functions

Useful commands

• npm run build compile typescript to js
• npm run watch watch for changes and compile
• npm run test perform the jest unit tests
• cdk deploy deploy this stack to your default AWS account/region
• cdk diff compare deployed stack with current state
• cdk synth emits the synthesized CloudFormation template

Deploy

Using make command

1. Install all the dependencies, bootstrap your project, and synthesized CloudFormation template.

   # Without passing "profile" parameter
   dev@dev:~:aws-cdk-samples/step-functions/step-functions-sns$ make init
   
   # With "profile" parameter
   dev@dev:~:aws-cdk-samples/step-functions/step-functions-sns$ make init profile=[profile_name]

2. Deploy the project.

   # Without passing "profile" parameter
   dev@dev:~:aws-cdk-samples/step-functions/step-functions-sns$ make deploy
   
   # With "profile" parameter
   dev@dev:~:aws-cdk-samples/step-functions/step-functions-sns$ make deploy profile=[profile_name]