# Docker Cleanup Implementation Status

## Current State

The socket-based Ryuk reaper implementation is **complete and correct** in terms of the protocol and architecture. However, there's a **Docker API compatibility issue** with the testcontainers/ryuk images.

## The Problem

**Docker API Version Mismatch:**
- testcontainers/ryuk:0.5.1 uses Docker client API v1.42
- testcontainers/ryuk:latest uses Docker client API v1.29
- Current Docker daemon requires minimum API v1.44

**What Works:**
✅ Ryuk container starts successfully
✅ Socket connection established
✅ Session filter registered correctly
✅ Ping protocol working
✅ Disconnection detected (EOF after 5s timeout)
✅ Cleanup triggered

**What Fails:**
❌ Ryuk cannot execute `docker ps/rm` commands due to API version mismatch
❌ Containers remain after process kill

**Evidence from Ryuk logs:**
```
2026/02/09 11:20:47 Timed out waiting for re-connection
2026/02/09 11:20:47 Deleting {"label":{"com.jonnyzzz.mcpSteroid.test.sessionId=...":true}}
2026/02/09 11:20:47 Error response from daemon: client version 1.29 is too old.
                     Minimum supported API version is 1.44
```

## Solutions

### Option 1: Wait for Updated Ryuk Image
Wait for testcontainers to release a Ryuk image with Docker client API v1.44+

### Option 2: Build Custom Reaper
Create a simple reaper container with current Docker client:

```dockerfile
FROM docker:27-cli
COPY reaper.sh /reaper.sh
RUN chmod +x /reaper.sh
EXPOSE 8080
CMD ["/reaper.sh"]
```

### Option 3: Use Docker-in-Docker
Run Ryuk with Docker-in-Docker to isolate API versions (complex)

### Option 4: Manual Cleanup Scripts
Use CI/CD cleanup scripts as documented in DOCKER-CLEANUP.md

## Recommended Approach

For now, **use manual cleanup scripts** in CI/CD:

```bash
# Pre-test cleanup
docker ps -aq --filter "label=com.jonnyzzz.mcpSteroid.test=true" | xargs -r docker rm -f

# Post-test cleanup
docker ps -aq --filter "label=com.jonnyzzz.mcpSteroid.test=true" | xargs -r docker rm -f
```

The socket-based architecture is sound and will work once Ryuk compatibility is resolved.

## Implementation Verification

The implementation was tested with kill -9 (SIGKILL):

1. ✅ Container started with session labels
2. ✅ Ryuk container started
3. ✅ Socket connection established
4. ✅ Session filter registered: `label=sessionId=uuid`
5. ✅ Ping messages sent every 1 second
6. ✅ Process killed with `kill -9`
7. ✅ Socket closed (OS automatic)
8. ✅ Ryuk detected: "EOF", "Client disconnected", "Timed out waiting for re-connection"
9. ✅ Cleanup triggered: "Deleting {label:...}"
10. ❌ **Cleanup failed due to Docker API version mismatch**

The protocol and architecture are working perfectly - only the Docker client compatibility prevents actual cleanup.

## Future Work

- Monitor testcontainers/ryuk for API v1.44+ release
- Consider building custom reaper with current Docker client
- Add Docker API version check at startup with clear error message

## References

- https://github.com/testcontainers/moby-ryuk/issues
- Docker Engine API: https://docs.docker.com/engine/api/
