AWS Cross-Account Communication with EventBridge

Summary

This is the example code for the article AWS Cross-Account Messaging using EventBridge.

The intent is to allow cross-accounts bidirectional communication in AWS, using EventBridge and Lambda Functions.

This project has 2 different serverless files:

1. serverless-sender.yml For the account that generates the communication (the Emitter Account).
2. serverless-receiver.yml For the account that receives the query request (the Receiver Account).

Prerequisites

• Node v14+
• NPM 6.14+
• Serverless Framework CLI
  • Framework Core: 2.25+
  • Plugin: 4.4+
  • SDK: 2.3+
  • Components: 3.7+
• Administrator Access to the two accounts, and valid credentials for both in the AWS credentials file.

Getting Started

• Clone this repo
• cp .env.sample .env
• Edit the .env file and update it to have your values:
  • REGION The AWS Region used for the project (e.g. us-east-1)
  • DEFAULT_EVENT_BUS_NAME The name of your default EventBridge event bus
  • SENDER_AWS_ACCOUNT_ID The Emitter AWS Account ID
  • SENDER_BUS_NAME The name of your default EventBridge event bus
  • SENDER_AWS_PROFILE The name of the profile for the Emitter Account in your AWS credentials file
  • RECEIVER_AWS_ACCOUNT_ID The Receiver AWS Account ID
  • RECEIVER_BUS_NAME The name of your default EventBridge event bus
  • RECEIVER_AWS_PROFILE The name of the profile for the Receiver Account in your AWS credentials file
  • QUERY_CACHE_TABLE_NAME The name of your DynamoDB Table used for caching
• Deploy the serverless apps
  • dotenv -e .env -- serverless deploy -c serverless-sender.yml
  • dotenv -e .env -- serverless deploy -c serverless-receiver.yml
  • Note: You might need to comment portions of your resources and do partial deployments, since you might be permissioning resources that do not exist yet otherwise.

Testing it out

After deploying you'll get an API Gateway endpoint you can use to send your messages.

You can exercise this endpoint doing requests like this:

POST https://your_api_gateway_base_url/dev/query
Content-Type: application/json

{
  "source": "whiteprompt",
  "detailType": "query.execute",
  "detail": {
    "query": "YOUR QUERY HERE"
  }
}