SNS/SQS integration libraries

Libraries that speak CNCF into SNS and out of SQS.

Modeled SNS to SQS subscription on https://github.com/aws/aws-sdk-java/blob/aaa0a6f506314d314a77774ddadd303cf6e4c354/aws-java-sdk-sns/src/main/java/com/amazonaws/services/sns/util/Topics.java#L181

Created IAM policy based on https://docs.aws.amazon.com/sdk-for-go/v1/developer-guide/iam-example-policies.html

See also: https://aws.amazon.com/blogs/developer/subscribing-queues-to-topics/ https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-add-permissions.html https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-writing-an-sqs-policy.html