Circuit breaker exception chain changed with 5.23.0

[moellermarc]

Describe the Bug

Hello Cloud SDK team,

after upgrading to Cloud SDK 5.23.0, some of our unit tests across several microservices started failing. It looks like the resilience decorator now raises a different exception chain. Release notes: https://sap.github.io/cloud-sdk/docs/java/release-notes#5230---october-08-2025 (Improvements).

Since the change, we haven’t found a reliable way to detect when the circuit breaker is open. Previously, we could check for a CallNotPermittedException in the exception chain.
When the circuit breaker is open, we need to:

• Log the event for internal operations
• Provide a corresponding error message to inform end users about the situation

Could you please advise on the recommended approach in 5.23.0+ to detect an open circuit breaker from the exception chain?

Thank you!

Steps to Reproduce

If helpful, we can reproduce and show this in our internal environment, depending on the next steps.
Contact: marc-andre.moeller@sap.com

Expected Behavior

We’d expect changes like this were reserved for major releases, along with a supported way to detect when the circuit breaker is open (from the exception chain).

Screenshots

No response

Used Versions

Cloud SDK 5.23.0

Code Examples

try {
			ResilienceDecorator.executeCallable(() -> {
				client.tradeRequestTRMBulkTransferConfirmationIn(request);
				return null;
			}, resilienceConfiguration);
		} catch (Exception e) {
			throw s4AdapterExceptionHelper.unwrapException(e, S4WebService.TRADE_REQUESTS_TRIGGER_TRANSFER);
		}

Stack Trace

No response

Log File

No response

Affected Development Phase

Production

Impact

Impaired

Timeline

No response

[Jonas-Isr]

Hi @moellermarc,

thanks for reaching out! We will look into this issue and a possible solution and will get back to you as soon as we have more info.

Best,
Jonas

[Jonas-Isr]

Hi @moellermarc,

to keep you up to date:

Since the change, we haven’t found a reliable way to detect when the circuit breaker is open. Previously, we could check for a CallNotPermittedException in the exception chain.

Yes, there is currently no way to check this just via the exception chain. As a (probably unsatisfactory) workaround you can check the docs for a message containing "Circuit breaker" and "is open". But I do understand that this is probably not what you expect.

As some background information: We did this change to make it easier for users (and us) to troubleshoot the actual reason that caused the circuit breaker to open. This was not easy to find out with the previous behaviour.

We understand your need for a way to reliably detect the opening of the circuit breaker, however, and are currently working on a solution that enables this and at the same time also makes it easy to understand the root cause of the circuit breaker opening.

We will get back to you here once we have a working implementation.

Best,
Jonas

[moellermarc]

Hi @Jonas-Isr ,

thanks for the detailed explanation!
For now, we’ll stay on 5.22.0 and hope for a fix in the next minor release.

Best regards,
Marc

[Jonas-Isr]

Hi @moellermarc,

can you look at this PR and check whether something like this would be an acceptable solution for you?

Best,
Jonas