fix: preserve external annotations on reconciler Deployment updates#468
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Defilan merged 5 commits intoMay 14, 2026
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Both the ModelRouter and the InferenceService reconcilers updated their managed Deployment by replacing the pod template wholesale: // router_deployment_builder.go existing.Spec.Template = desired.Spec.Template existing.Labels = desired.Labels // inferenceservice_controller.go existingDeployment.Spec = deployment.Spec That strips every annotation an external actor set on the pod template: sidecar injectors (Istio, Linkerd), `kubectl rollout restart`'s `kubectl.kubernetes.io/restartedAt`, GitOps tool sync labels. The most visible symptom is a `kubectl rollout restart` spinning two ReplicaSets that flap against each other as the controller's reconcile fights kubectl's annotation, and in-flight requests get truncated. Fix it the same way in both places: a small helper that merges operator-owned keys over external keys (desired wins on collision, foreign keys pass through). Spec replacement otherwise stays wholesale so the existing rollout-on-config-hash mechanism keeps working. Coverage: - mergePreservingExternal unit test (4 cases: empty/desired-only/ external-only/collision) - New router-proxy reconcile test exercising the end-to-end fix through the fake client: seed a Deployment carrying both operator-owned and externally-set annotations, run reconcileRouterDeployment with a new config hash, assert the operator's hash advances AND every external key on the pod template + top-level Deployment metadata survives Also lands a "Phase 1 limitations" section in the ModelRouter concept doc covering the three v1alpha1 gaps the release-readiness audit surfaced: timeouts cap TTFT not stream duration, audit log lacks token/byte metrics, inbound bodies are buffered. Framed as v1alpha1 scope rather than apology so users running opencode / Claude Code / Aider know where to put their safety nets without filing a bug. Fixes defilantech#456. Signed-off-by: Christopher Maher <chris@mahercode.io>
The 0.7.8 release-readiness audit surfaced three honest gaps in the Phase 1 router-proxy that show up under agentic-coding load: TTFT-only timeouts (no stream-duration cap), coarse audit log (no token/byte/stream-duration metrics), and buffered inbound request bodies. Document them as v1alpha1 scope rather than discover-during-incident so opencode / Claude Code / Aider users know where to put their client-side safety nets and what's planned for Phase 2. Placement: own section between "What's in scope" and "Comparison to alternatives". Cross-links defilantech#433 (token/byte metrics) for the audit-log gap. Signed-off-by: Christopher Maher <chris@mahercode.io>
Codecov Report❌ Patch coverage is 📢 Thoughts on this report? Let us know! |
CI lint surfaced four issues on the prior commit: * QF1008 ×3 in inferenceservice_controller.go and router_deployment_builder.go: PodTemplateSpec embeds ObjectMeta, so `.Spec.Template.ObjectMeta.Labels` and friends collapse to `.Spec.Template.Labels`. Same semantics, less noise. * goconst ×1 in router_builders_test.go: the new test used the literal `"llmkube"` twice for an `argocd.argoproj.io/instance` value, which combined with the existing production usage in router_common.go tripped goconst's 3-occurrence threshold. The test fixture doesn't need to share that string with production; switched to `"coding-router-fleet"` and pulled it into a local const so future drift is at least localized. No behavior change; lint-only. Signed-off-by: Christopher Maher <chris@mahercode.io>
…unit tests The unit + fake-client tests in this PR catch any regression of the mergePreservingExternal path, but the kind-cluster merge gate had no coverage for the user-visible symptom of defilantech#456 (external pod-template annotations stomped by a wholesale Spec.Template replace). Add a real e2e step inside the existing ModelRouter Reconciliation Context that: 1. Reuses the e2e-good-router proxy Deployment the previous test already stood up. 2. Patches the Deployment's pod template with the two annotations real-world users hit: sidecar.istio.io/inject (Istio sidecar injector) and kubectl.kubernetes.io/restartedAt (`kubectl rollout restart`). 3. Forces a controller reconcile by bumping spec.proxy.replicas on the ModelRouter from 1 to 2 (the controller's watch on ModelRouter guarantees a Reconcile() cycle that walks reconcileRouterDeployment). 4. Waits for spec.replicas to be 2 on the Deployment (proves the reconcile actually ran). 5. Asserts the two external annotations are still present AND the operator-owned config-hash annotation is also still present (so we know we're not accidentally preserving external keys at the cost of operator keys). Without the fix this It block fails at step 5; with the fix it passes. The kind merge gate will now block any regression at PR time instead of only catching it via the unit / fake-client suite. The test runs in the same Context as the existing reconcile and validation tests, so it adds no new namespace / fixture setup overhead. ~30s additional runtime. Signed-off-by: Christopher Maher <chris@mahercode.io>
The MicroShift / MINC e2e lane has been flaking on the OpenShift SCC admission test with a confusing error that PR defilantech#466's improved diagnostics finally surfaced: deployments.apps "scc-test-inference" is forbidden: cannot set blockOwnerDeletion in this case because cannot find RESTMapping for APIVersion inference.llmkube.dev/v1alpha1 Kind InferenceService: no matches for kind "InferenceService" in version "inference.llmkube.dev/v1alpha1" Trace: controller-runtime's controllerutil.SetControllerReference sets BlockOwnerDeletion=true by default. The kube-apiserver GarbageCollector admission plugin validates that flag by RESTMapping the owner Kind to check the caller's `update` permission on the owner's `finalizers` subresource. On kind the API server's discovery cache is warm by the time the controller starts; on MicroShift-in- MINC, the in-container apiserver populates discovery lazily on first request, and the controller's first reconcile races it and loses. We do not need BlockOwnerDeletion. Cascading delete still cleans up operator-managed Deployments/Services/ConfigMaps/HPAs when their parent ModelRouter or InferenceService is deleted; the "block" semantics only matter for finalizer-based cleanup workflows LLMKube does not use. Trade: cleaner bootstrap for slightly looser cascade ordering guarantees we weren't relying on. Fix: new setControllerReferenceUnblocked helper that wraps controllerutil.SetControllerReference and clears BlockOwnerDeletion on the owner ref it just installed. Applied to all 9 call sites in the controller package (router deployment / service / configmap, both InferenceService and ModelRouter reconcilers, HPA reconciler). Coverage: TestSetControllerReferenceUnblocked verifies the resulting owner ref has Controller=true and BlockOwnerDeletion=false. Existing tests in router_builders_test.go and modelrouter_controller_test.go continue to pass — the change is in the metadata, not the spec. Side benefit: removes the controllerutil import from five files that no longer need it. Signed-off-by: Christopher Maher <chris@mahercode.io>
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What
Two related fixes that together make 0.7.8 ship-ready for the audience watching Marcel's video.
Fix 1: preserve external pod-template annotations on reconcile (closes #456)
Both the ModelRouter and the InferenceService reconcilers were replacing the pod template wholesale:
That stripped every annotation an external actor set on the pod template: sidecar injectors (Istio, Linkerd),
kubectl rollout restart'skubectl.kubernetes.io/restartedAt, GitOps tool sync labels. The visible symptom was akubectl rollout restartspinning two ReplicaSets that flap against each other while the controller's reconcile fought kubectl's annotation, and in-flight requests got truncated.Fixed by adding a
mergePreservingExternal(existing, desired)helper. Operator-owned keys win on collision; foreign keys pass through. Spec replacement otherwise stays wholesale so the existing config-hash rollout mechanism keeps working.Fix 2: drop BlockOwnerDeletion on operator-managed children
While running the MicroShift / MINC lane, PR #466's improved diagnostics surfaced a real flake:
controller-runtime's
SetControllerReferencesetsBlockOwnerDeletion=trueby default. The kube-apiserverGarbageCollectoradmission plugin validates that flag by RESTMapping the owner Kind to check the caller'supdatepermission on the owner'sfinalizerssubresource. On kind the API server's discovery cache is warm by the time the controller starts. On MicroShift-in-MINC, the in-container apiserver populates discovery lazily on first request and the controller's first reconcile races it and loses.LLMKube doesn't need
BlockOwnerDeletion. Cascading delete still cleans up operator-managed children when their parent CR is deleted; the "block" semantics only matter for finalizer-based cleanup workflows we don't use. Trade-off: cleaner bootstrap for slightly looser cascade ordering guarantees we weren't relying on.Fixed by a new
setControllerReferenceUnblockedhelper that wrapscontrollerutil.SetControllerReferenceand clearsBlockOwnerDeletionon the owner reference. Applied to all 9 call sites: router Deployment/Service/ConfigMap reconcilers, InferenceService Deployment/Service reconcilers, and the HPA reconciler.Why
#456is filed today and is a real ergonomic / correctness problem for any cluster running a service mesh, ArgoCD, or kubectl rollout-restart. The MicroShift flake has been blocking CI signal across multiple recent PRs (#464, #466, this one). Marcel Dempers' YouTube video is driving traffic right now; the operator needs to behave predictably for first-time users on real clusters before we cut 0.7.8.Fixes #456.
How
Annotation preservation:
mergePreservingExternalininternal/controller/merge.goBlockOwnerDeletion:
setControllerReferenceUnblockedininternal/controller/ownerref.gocontrollerutil.SetControllerReference, then walks the resulting owner refs and clearsBlockOwnerDeletionon the one we just installedCoverage:
TestMergePreservingExternal— helper unit test (4 cases)TestSetControllerReferenceUnblocked— verifies the resulting owner ref hasController=trueandBlockOwnerDeletion=falseTestReconcileRouterDeploymentPreservesExternalAnnotations— full fake-client integration test for the annotation fixshould preserve external pod-template annotations across reconciles (#456)in theModelRouter ReconciliationContext patches the proxy Deployment with sidecar/kubectl-rollout-restart annotations, bumpsspec.proxy.replicasto force reconcile, then Eventually-asserts the external annotations survive AND the operator-owned config-hash annotation is also still presentmake lint,make test,go vet -tags=e2e ./test/e2e/...all cleanChecklist
go test ./internal/controller/...passes locallymake lintpasses locallyfix:,docs(site):,fix(lint):,test(e2e):,fix:for BlockOwnerDeletion)git commit -s) per DCOconcepts/model-router.md)