Lambda loop detection now covers EventBridge custom buses!

Hi, it's Shii-chan! This update protects you from the scary infinite loop.

AWS What's New aws.amazon.com

What was announced?

AWS What's New says Lambda recursive loop detection now supports Amazon EventBridge custom event buses. It automatically detects and stops recursive loops between Lambda event functions and EventBridge custom buses.

The story so far

Recursive loop detection finds Lambda functions that are invoked recursively by a supported AWS service and stops the loop. It is enabled by default on your account. But EventBridge custom buses weren't covered.

When you invoke Lambda from a custom bus, a misconfiguration or code defect can make EventBridge rules trigger your function recursively. That leads to runaway usage and unexpected charges.

What changes

Now those loops are stopped automatically, and you get an AWS Health Dashboard notification with troubleshooting instructions. You're protected from unintended usage and charges.

Dive Deep

• No configuration needed; it's enabled by default on your account
• Available in every commercial AWS Region where EventBridge custom event buses are available
• If a function uses recursion on purpose, you can turn detection off for that function with the PutFunctionRecursionConfig API

Wrap-up

• Loop detection now supports EventBridge custom buses
• Loops are stopped automatically with a Health Dashboard notification
• No setup, all commercial Regions
• Use PutFunctionRecursionConfig for intentional recursion

One more safety net if you build event-driven automation with EventBridge and Lambda!