Export ESF queue and function ARNs as CloudFormation outputs

[lewismarsden-xft]

Describe the enhancement:

It would be useful to have access to the ARNs of the SQS queues and the Lambda function created for the ESF as part of the application deployment to use in other CloudFormation stacks built outside of the ESF.

This includes the following ESF resources (four SQS queues, one Lambda function) that are created as part of the forwarder application's nested stack (using the logical IDs in the stack):

• ElasticServerlessForwarderContinuingDLQ
• ElasticServerlessForwarderContinuingQueue
• ElasticServerlessForwarderReplayDLQ
• ElasticServerlessForwarderReplayQueue
• ApplicationElasticServerlessForwarder

Describe a specific use case for the enhancement or feature:

These outputs would be useful to set up some additional form of monitoring on the ESF, e.g.:

• Add a CloudWatch Alarm to monitor the error rate of the forwarder function
• Set up an EventBridge rule to monitor the DLQs, and notify an SNS topic if there are messages

At the moment, any of these additional resources would need to be created separately after manually sourcing the ARNs of the created ESF resources, so cannot be used in a single deployment (e.g. a CDK stack deployment with a dependency). Two separate deployments are needed, as the ESF must be deployed before any supplementing resources.

[aspacca]

@lewismarsden-xft. we'll add the feature request to our planning and keep you posted on the progress

[aspacca]

@lewismarsden-xft outputs for Lambda function ARN and IAM Role ARN were added on v1.12.0.

I will keep the issue open for adding:

• ElasticServerlessForwarderContinuingDLQ
• ElasticServerlessForwarderContinuingQueue
• ElasticServerlessForwarderReplayDLQ
• ElasticServerlessForwarderReplayQueue