Description
New 26.7 core surface (Routing/Api/GroupSettingsController.php): gateway failover-group topology — which gateways sit in which group/tier. Pairs with existing gateway status metrics to answer “is this failover group degraded”. Plugin/version-gated behaviour: on pre-26.7 boxes the endpoint 404s — treat as feature-absent per the plugin-gated pattern.
Acceptance Criteria
- #1 Group membership/tier exported as metrics joinable with existing gateway status series
- #2 404 on pre-26.7 handled as feature-absent (negative-cacheable), collector silent
- #3 AGENTS.md new-collector steps complete; gates clean
Definition of Done
- #1 just check
- #2 just gen (if any generated artifact changed) and the diff committed
Implementation Plan
Reconstruct the source-derived gateway-group collector, wire its 26.7 feature-absence contract through the root-owned endpoint/schema/cache/collector registries, add dashboard coverage, regenerate artifacts, run targeted and full gates, complete sliced CodeRabbit review, then finalize and land one green commit.
Implementation Notes
Root integration added the 26.7 gatewayGroups GET route, semantic and negative-cacheable 404 handling, schema/ACL registration, cold polling, default-on disable switch, main wiring, generated docs/schema, and dashboard coverage. CodeRabbit pass 1 found a major join defect: group address was configured gateway while gateways_status address was monitor address and disabled gateways emitted no status. Failing active/disabled join tests reproduced both defects; the fix exposes monitor address as the join label, retains gateway_address separately, and emits disabled status with the upstream ~ sentinel. CodeRabbit pass 2 completed with zero findings. just gen reported 66 collectors, 1,053/1,053 dashboard coverage, and 180 schemas. just check passed: 427 Grafana tests, 1,210 Prometheus targets, 80 manifests, and govulncheck found no called vulnerabilities.
Final Summary
Added joinable gateway failover-group membership metrics with pre-26.7 silent feature absence. Verified targeted race tests, source-derived upstream behavior, two completed CodeRabbit passes with the sole major fixed, just gen, and the full just check gate.