---
phase: 03-agent-registry-sse-push
plan: 02
subsystem: agent-sse
tags: [sse, server-sent-events, sseemitter, command-push, ping-keepalive, spring-scheduled]

# Dependency graph
requires:
  - phase: 03-agent-registry-sse-push
    provides: AgentRegistryService, AgentEventListener, AgentCommand, CommandType, AgentRegistryConfig
provides:
  - SseConnectionManager with per-agent SseEmitter management and event delivery
  - AgentSseController GET /api/v1/agents/{id}/events SSE endpoint
  - AgentCommandController with single/group/broadcast command targeting
  - Command acknowledgement endpoint POST /{id}/commands/{commandId}/ack
  - Ping keepalive every 15 seconds via @Scheduled
  - Last-Event-ID header support (no replay)
affects: [04-security]

# Tech tracking
tech-stack:
  added: []
  patterns: [sse-emitter-per-agent, reference-equality-removal, async-command-delivery-via-event-listener]

key-files:
  created:
    - cameleer3-server-app/src/main/java/com/cameleer3/server/app/agent/SseConnectionManager.java
    - cameleer3-server-app/src/main/java/com/cameleer3/server/app/controller/AgentSseController.java
    - cameleer3-server-app/src/main/java/com/cameleer3/server/app/controller/AgentCommandController.java
    - cameleer3-server-app/src/test/java/com/cameleer3/server/app/controller/AgentSseControllerIT.java
    - cameleer3-server-app/src/test/java/com/cameleer3/server/app/controller/AgentCommandControllerIT.java
  modified:
    - cameleer3-server-app/src/main/java/com/cameleer3/server/app/config/WebConfig.java
    - cameleer3-server-app/src/test/resources/application-test.yml

key-decisions:
  - "SSE events path excluded from ProtocolVersionInterceptor for EventSource client compatibility"
  - "SseConnectionManager uses reference-equality (==) in onCompletion/onTimeout/onError to avoid removing a newer emitter"
  - "java.net.http.HttpClient async API for SSE integration tests to avoid test thread blocking"

patterns-established:
  - "AgentEventListener bridge: core module fires event, app module @Component delivers via SSE"
  - "CountDownLatch + async HttpClient for SSE integration test assertions"

requirements-completed: [AGNT-04, AGNT-05, AGNT-06, AGNT-07]

# Metrics
duration: 32min
completed: 2026-03-11
---

# Phase 3 Plan 2: SSE Push Summary

**SSE connection manager with per-agent SseEmitter, config-update/deep-trace/replay command delivery, group/broadcast targeting, ping keepalive, and command acknowledgement**

## Performance

- **Duration:** 32 min
- **Started:** 2026-03-11T17:44:10Z
- **Completed:** 2026-03-11T18:16:10Z
- **Tasks:** 2
- **Files modified:** 7

## Accomplishments
- SseConnectionManager with ConcurrentHashMap-based per-agent SSE emitter management, ping keepalive, and AgentEventListener bridge
- Three command targeting levels: single agent, group, and broadcast to all LIVE agents
- 7 SSE integration tests (connect, 404 unknown, config-update/deep-trace/replay delivery, ping, Last-Event-ID) + 6 command controller tests
- All 71 tests pass with mvn clean verify

## Task Commits

Each task was committed atomically:

1. **Task 1: SseConnectionManager, SSE controller, and command controller** - `5746886` (feat)
2. **Task 2: Integration tests for SSE, commands, and full flow** - `a1909ba` (test)

## Files Created/Modified
- `SseConnectionManager.java` - Per-agent SseEmitter management, event delivery, ping keepalive via @Scheduled
- `AgentSseController.java` - GET /{id}/events SSE endpoint with Last-Event-ID support
- `AgentCommandController.java` - POST command endpoints (single/group/broadcast) + ack endpoint
- `AgentSseControllerIT.java` - 7 SSE integration tests using async HttpClient
- `AgentCommandControllerIT.java` - 6 command controller integration tests
- `WebConfig.java` - Added SSE events path to interceptor exclusion list
- `application-test.yml` - Added 1s ping interval for faster SSE test assertions

## Decisions Made
- Excluded SSE events path from ProtocolVersionInterceptor -- EventSource clients cannot easily add custom headers, so the SSE endpoint is exempted from protocol version checking
- Used reference equality (==) in SseEmitter callbacks to avoid removing a newer emitter when an old one completes -- directly addresses Pitfall 3 from research
- Used java.net.http.HttpClient async API for SSE integration tests instead of adding spring-boot-starter-webflux -- avoids new dependencies and tests true end-to-end behavior

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered
- Surefire fork JVM hangs ~30s after SSE tests complete due to async HttpClient threads holding JVM open -- not a test failure, just slow shutdown. Surefire eventually kills the fork.

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness
- Full bidirectional agent communication complete: agents POST data, server pushes commands via SSE
- Phase 4 (Security) can add JWT auth to all endpoints and Ed25519 config signing
- All agent endpoints under /api/v1/agents/ ready for auth layer

## Self-Check: PASSED

- All 5 created files exist on disk
- Commit `5746886` found in git log (Task 1)
- Commit `a1909ba` found in git log (Task 2)
- `mvn clean verify` passes with 71 tests, 0 failures

---
*Phase: 03-agent-registry-sse-push*
*Completed: 2026-03-11*
