# Router TimelineIndexer Microservice Pilot

## Scope
- Pilot service: `TimelineIndexer` (`src/Timeline/StellaOps.TimelineIndexer.WebService`).
- Transport: `TransportType.Messaging` backed by Valkey.
- Gateway entry under pilot: `/api/v1/timeline*`.

## Baseline
- Previous gateway route:
- `ReverseProxy /api/v1/timeline -> http://timelineindexer.stella-ops.local/api/v1/timeline`
- Reverse proxy mode strips the matched prefix before forwarding.
- Microservice mode does not strip prefixes and routes by method+path identity.

## Path Compatibility Mapping
| External path | Reverse proxy behavior | Required microservice path | Pilot status |
| --- | --- | --- | --- |
| `/api/v1/timeline` | proxied to `/api/v1/timeline` upstream | `/api/v1/timeline` | converted |
| `/api/v1/timeline/{eventId}` | proxied to `/api/v1/timeline/{eventId}` upstream | `/api/v1/timeline/{eventId}` | converted |
| `/api/v1/timeline/{eventId}/evidence` | proxied to `/api/v1/timeline/{eventId}/evidence` upstream | `/api/v1/timeline/{eventId}/evidence` | converted |
| `/api/v1/timeline/events` | proxied to `/api/v1/timeline/events` upstream | `/api/v1/timeline/events` | converted |
| `/timelineindexer/*` | reverse-proxy prefix path for direct service access | unchanged (still reverse proxy) | unchanged |

TimelineIndexer now exposes both native and gateway-alias endpoints:
- native: `/timeline*`
- gateway alias: `/api/v1/timeline*`

## Compose Activation
- Gateway messaging toggle: `ROUTER_GATEWAY_MESSAGING_ENABLED` (default `true`).
- TimelineIndexer router toggle: `TIMELINE_ROUTER_ENABLED` (default `true`).
- Compose env vars are applied on `timeline-indexer-web` (not `vexlens-web`) and mapped to:
- `TimelineIndexer:Router`
- `TimelineIndexer:Router:TransportPlugins:*`
- `TimelineIndexer:Router:Messaging:*`
- Valkey backend selection is environment-driven via `TimelineIndexer:Router:Messaging:Transport=valkey`.

## Rollback
1. Set `TIMELINE_ROUTER_ENABLED=false` and `ROUTER_GATEWAY_MESSAGING_ENABLED=false` in compose environment.
2. Revert route entry in `devops/compose/router-gateway-local.json` from `Microservice` back to `ReverseProxy`.
3. Re-deploy stack and verify `/api/v1/timeline*` responses through reverse proxy path.