Update Harbor client and gateway integration workflows

src/web/state/harborReducer.ts

@@ -4,6 +4,10 @@ export type SyncErrorKind = 'incompatible-api' | 'control-unreachable' | 'fatal'
 
 export interface HarborReducerState {
   snapshot: HarborClientState | null;
+  failoverTransport: {
+    activeEpoch: string;
+    retiredEpochs: string[];
+  };
   transport: {
     bootStatus: 'loading' | 'ready' | SyncErrorKind;
     lastSuccessfulSyncAt: string | null;
@@ -20,6 +24,7 @@ export type HarborAction =
 
 export const initialHarborState: HarborReducerState = {
   snapshot: null,
+  failoverTransport: { activeEpoch: '', retiredEpochs: [] },
   transport: {
     bootStatus: 'loading',
     lastSuccessfulSyncAt: null,
@@ -31,6 +36,14 @@ export const initialHarborState: HarborReducerState = {
 
 export const STALE_FAILURE_THRESHOLD = 3;
 
+function failoverEpoch(snapshot: HarborClientState | null) {
+  return snapshot?.failover?.observationEpoch || '';
+}
+
+function failoverSequence(snapshot: HarborClientState | null) {
+  return snapshot?.failover?.observationSequence || 0;
+}
+
 export function classifySyncError(error: unknown): SyncErrorKind {
   const candidate = error && typeof error === 'object' ? error as Record<string, unknown> : {};
   const status = Number(candidate.status) || 0;
@@ -71,9 +84,29 @@ export function harborReducer(current: HarborReducerState, action: HarborAction)
 
   const snapshot = action.snapshot;
   const newer = !current.snapshot || snapshot.revision > current.snapshot.revision;
+  const equal = Boolean(current.snapshot) && snapshot.revision === current.snapshot?.revision;
+  const incomingEpoch = failoverEpoch(snapshot);
+  const activeEpoch = current.failoverTransport.activeEpoch || failoverEpoch(current.snapshot);
+  const unseenEpoch = Boolean(incomingEpoch)
+    && incomingEpoch !== activeEpoch
+    && !current.failoverTransport.retiredEpochs.includes(incomingEpoch);
+  const newerObservation = equal && Boolean(snapshot.failover) && (
+    unseenEpoch
+    || (incomingEpoch === activeEpoch && failoverSequence(snapshot) > failoverSequence(current.snapshot))
+  );
+  const nextSnapshot = newer
+    ? snapshot
+    : newerObservation && current.snapshot
+      ? { ...current.snapshot, failover: snapshot.failover }
+      : current.snapshot;
+  const nextActiveEpoch = newer || unseenEpoch ? incomingEpoch : activeEpoch;
+  const retiredEpochs = unseenEpoch && activeEpoch
+    ? [...current.failoverTransport.retiredEpochs, activeEpoch]
+    : current.failoverTransport.retiredEpochs;
 
   return {
-    snapshot: newer ? snapshot : current.snapshot,
+    snapshot: nextSnapshot,
+    failoverTransport: { activeEpoch: nextActiveEpoch, retiredEpochs },
     transport: {
       bootStatus: 'ready',
       lastSuccessfulSyncAt: action.receivedAt,

src/web/state/operations.ts

@@ -1,6 +1,6 @@
 export type OperationKey = 'connection' | 'serverApply' | 'profileAdd' | 'profileRename'
   | 'profileSelect' | 'profileActivate' | 'profileRefresh' | 'profileDelete'
-  | 'gatewayAuto' | 'routeRules' | 'diagnosticsSettings';
+  | 'gatewayAuto' | 'routeRules' | 'diagnosticsSettings' | 'failover';
 
 export interface OperationState {
   status: 'running';
@@ -22,6 +22,7 @@ const OPERATION_KEYS: readonly OperationKey[] = [
   'gatewayAuto',
   'routeRules',
   'diagnosticsSettings',
+  'failover',
 ];
 
 // The backend has one canonical revision and one mutation queue, so the UI mirrors that lock.