Update CloudFormation template to create log group & stream on deploy

[sanchitmalhotra126]

Updates the main cloudformation template with a step to create a browser events Log Group and Log Stream for the given stack. Some implementation notes:

• Ideally, the rails application would be able to receive variables like the log group/stream names directly from the Cloudformation template; however we don't currently have a good way to do that, so we are instead calculating the name in a predictable way, in both the template and the Rails controller independently
• In order to satisfy existing role permissions, the Log Group name needs to be prefixed with the environment name. However, we also want the log group & stream to be unique per adhoc instance, so adhocs are not all writing to the same group. To do this I needed to add some conditional logic that uses the stack_name if on an adhoc (which is the full "adhoc-my-adhoc-name") or environment otherwise (which is "production", "test", etc). We can't just use stack_name because on production, this returns autoscale-prod which isn't as clear and wouldn't satisfy the constraint of the log group name needing to be prefixed with the environment name.
  • On adhocs, the log group will look like "adhoc-my-branch-name-browser-events" and the log stream will look like "adhoc-my-branch-name".
  • On other environments, the log group should look like "production-browser-events" and the log stream should just be "production"
• Originally, we were planning on using the domain name as a unique identifier. However this posed two issues - due to the existing role permissions, we'd still have to prefix with the environment name (or add a new resource name to the allow list), and on adhocs, the template uses code.org as the BaseDomainName, which doesn't match what the Rails controller calculates as the base domain, which is cdn-code.org. We could use the <%=domain> value inside the template to get cdn-code.org but this felt unnecessarily verbose given we were already prefixing the name with the environment.

Links

https://codedotorg.atlassian.net/browse/SL-799

Testing story

Tested on an adhoc: https://adhoc-browser-events-template-test-studio.cdn-code.org/
Generated Log Group: https://us-east-1.console.aws.amazon.com/cloudwatch/home?region=us-east-1#logsV2:log-groups/log-group/adhoc-browser-events-template-test-browser-events
Generated Log Stream: https://us-east-1.console.aws.amazon.com/cloudwatch/home?region=us-east-1#logsV2:log-groups/log-group/adhoc-browser-events-template-test-browser-events/log-events/adhoc-browser-events-template-test

[sureshc]

Might be handy to rename this to logging and then Infrastructure team will add other logging Resources to this component in the future that are currently configured manually, provisioned in the top level template, or in some standalone template.

[sanchitmalhotra126]

Done!

[sureshc]

This looks great! Sorry the stack/domain naming turned out to be a hassle.