allthingssecurity opened a new pull request, #26769: URL: https://github.com/apache/camel/pull/26769
# Description [CAMEL-24922](https://issues.apache.org/jira/browse/CAMEL-24922) With `loadBalance().failover(-1, false, false, true)` (sticky, no round robin), the failover load balancer starts each exchange at the last known good endpoint and only moves forward. At the end of the list it gave up, so the endpoints before the last known good one were never tried again. Once that endpoint went down, every exchange failed, although other endpoints were up and `maximumFailoverAttempts` was `-1`. With `roundRobin=true` the same scenario recovered. This change: in sticky mode without round robin, when the end of the list is reached, failover continues from the first endpoint and stops once every endpoint has been tried once for the exchange. Sticky with round robin, and non-sticky modes, are unchanged. Tests: new `FailoverStickyWrapAroundTest`: - `testFailoverStickyContinuesFromFirstEndpoint`: `c` becomes the last good endpoint; then `c` goes down and `a` comes up. The exchange must fail over from `c` to `a`, and `a` becomes the new last good endpoint. - `testFailoverStickyTriesEachEndpointOnceWhenAllDown`: with all endpoints down, each is tried exactly once and the exchange fails. There's no endless loop. Without the fix, both tests fail (`mock://b Received message count. Expected: <1> but was: <0>`). With the fix, they pass together with the existing failover tests (`Failover*Test`, `FailOver*Test`: 21 tests, 0 failures). Found with a Lean 4 model of `FailOverLoadBalancer` (a proof that sticky mode tries every endpoint failed, which gave this counterexample), then reproduced against the real classes. # Target - [x] I checked that the commit is targeting the correct branch (Camel 4 uses the `main` branch) # Tracking - [x] If this is a large change, bug fix, or code improvement, I checked there is a [JIRA issue](https://issues.apache.org/jira/browse/CAMEL) filed for the change (usually before you start working on it). # Apache Camel coding standards and style - [x] I checked that each commit in the pull request has a meaningful subject line and body. - [ ] I have run `mvn clean install -DskipTests` locally from root folder and I have committed all auto-generated changes. (I built and tested the affected modules, `camel-core-processor` and `camel-core`, including the formatter and import-sort plugins. I did not run the full root build.) # AI-assisted contributions - [x] If this PR includes AI-generated code, commits have proper co-authorship attribution (e.g., `Co-authored-by` trailers) and the PR description identifies the AI tool used. This PR was prepared with Claude Code (Claude Opus 5.5). The commit carries a `Co-Authored-By` trailer. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
