Start Date: October 12, 2025
Implementation Status: 🟢 Phase 1 & 2 Complete
Branch: copilot/start-phase-2-implementation

File: src/painlessmesh/mesh.hpp

struct ConnectionInfo {
  uint32_t nodeId;           // Connected node ID
  uint32_t lastSeen;         // Timestamp of last message (ms)
  int rssi;                  // Signal strength (dBm)
  int avgLatency;            // Average round-trip time (ms)
  int hopCount;              // Hops from current node
  int quality;               // Connection quality (0-100)
  uint32_t messagesRx;       // Messages received
  uint32_t messagesTx;       // Messages sent
  uint32_t messagesDropped;  // Failed transmissions
};

• Returns std::vector<ConnectionInfo> of all direct connections
• Includes quality metrics from Connection class
• Used by topology reporter

• Calculates hop count to specific node
• Returns -1 if unreachable
• Returns 1 for direct connections, 2 for indirect (simplified)

• Returns std::map<uint32_t, uint32_t> (destination -> next hop)
• Currently only populates direct connections
• TODO: Implement full multi-hop routing table lookup

Added to Connection class:

uint32_t messagesRx = 0;
uint32_t messagesTx = 0;
uint32_t messagesDropped = 0;
uint32_t timeLastReceived = 0;
std::vector<uint32_t> latencySamples;
static const size_t MAX_LATENCY_SAMPLES = 10;

• Calculates average latency from rolling window (10 samples)
• Returns -1 if no samples available
• Used in quality calculation

• Calculates connection quality (0-100)
• Factors: latency, packet loss, RSSI
• Penalties:
  • High latency (>100ms): -1 per 5ms over threshold
  • Packet loss: -1 per 1% loss rate
  • Weak RSSI (<-80 dBm): -1 per dBm below threshold

• Platform-specific RSSI retrieval
• ESP32/ESP8266: Returns WiFi.RSSI()
• Other platforms: Returns 0
• Uses #ifdef guards for platform detection

File: examples/bridge/mesh_topology_reporter.hpp

Features:

• Generates schema-compliant topology messages (@alteriom/mqtt-schema v0.5.0)
• generateFullTopology() - Complete mesh snapshot with nodes, connections, metrics
• generateIncrementalUpdate() - Node join/leave events
• hasTopologyChanged() - Change detection to avoid redundant publishes
• Network metrics: diameter, avg quality, throughput
• ISO 8601 timestamps (placeholder, needs NTP integration)
• Alteriom device ID format: ALT-XXXXXXXXXXXX

JSON Structure:

{
  "schema_version": 1,
  "device_id": "ALT-6825DD341CA4",
  "device_type": "gateway",
  "timestamp": "2025-10-12T15:00:00Z",
  "firmware_version": "GW 2.3.4",
  "event": "mesh_topology",
  "mesh_id": "MESH-001",
  "gateway_node_id": "ALT-6825DD341CA4",
  "nodes": [...],
  "connections": [...],
  "metrics": {...},
  "update_type": "full"
}

File: examples/bridge/mesh_event_publisher.hpp

Features:

• Publishes real-time mesh events (@alteriom/mqtt-schema v0.5.0)
• publishNodeJoin() - New node entered mesh
• publishNodeLeave() - Node left mesh
• publishConnectionLost() - Direct connection failed
• publishConnectionRestored() - Connection recovered
• publishNetworkSplit() - Mesh partitioned
• publishNetworkMerged() - Partitions rejoined

Event Structure:

{
  "event": "mesh_event",
  "event_type": "node_join",
  "mesh_id": "MESH-001",
  "affected_nodes": ["ALT-441D64F804A0"],
  "details": {
    "total_nodes": 4,
    "timestamp": "2025-10-12T15:00:00Z"
  }
}

Location: examples/mqttCommandBridge/mqttCommandBridge.ino

Changes Required:

1. Add include: #include "examples/bridge/mesh_topology_reporter.hpp"
2. Create global instance: MeshTopologyReporter* topologyReporter;
3. Initialize in setup(): topologyReporter = new MeshTopologyReporter(mesh, "MESH-001");
4. Update taskTopology to use topologyReporter->generateFullTopology()
5. Change topic to: alteriom/mesh/MESH-001/topology

Estimated Effort: 30 minutes

Changes Required:

1. Add include: #include "examples/bridge/mesh_event_publisher.hpp"
2. Create global instance: MeshEventPublisher* eventPublisher;
3. Initialize in setup(): eventPublisher = new MeshEventPublisher(mesh, mqttClient, "MESH-001");
4. Update mesh.onNewConnection() callback to call eventPublisher->publishNodeJoin()
5. Update mesh.onDroppedConnection() callback to call eventPublisher->publishNodeLeave()

Estimated Effort: 30 minutes

Changes Required:

1. Create taskTopologyIncremental (5 second interval)
2. Check topologyReporter->hasTopologyChanged()
3. If changed, generate and publish incremental update
4. Add task to scheduler in setup()

Estimated Effort: 20 minutes

Location: examples/bridge/mqtt_command_bridge.hpp

Changes Required:

1. Add case 300 in command switch
2. Call topologyReporter->generateFullTopology()
3. Publish response to MQTT
4. Send command response with success=true

Estimated Effort: 15 minutes

Location: examples/mqttTopologyTest/mqttTopologyTest.ino (NEW)

Requirements:

• 3-node mesh setup (1 gateway + 2 sensors)
• Verify full topology published every 60s
• Verify incremental updates on node join/leave
• Verify events published correctly
• Log all messages to Serial

Estimated Effort: 2 hours

Location: test/catch/catch_topology_schema.cpp (NEW)

Test Cases:

• Topology message has envelope fields
• Topology message has nodes array
• Topology message has connections array
• Topology message has metrics object
• Event message has correct structure
• Device IDs match Alteriom format

Estimated Effort: 3 hours

Location: docs/MQTT_BRIDGE_COMMANDS.md

Sections to Add:

• Mesh Topology Reporting
• Mesh Events
• Topology command (300)
• Message examples

Estimated Effort: 1 hour

Location: docs/MESH_TOPOLOGY_GUIDE.md (NEW)

Content:

• How topology reporting works
• How to visualize with D3.js
• Troubleshooting topology issues
• Performance considerations

Estimated Effort: 2 hours

1. NTP Time Integration

   • Currently using millis()-based timestamps
   • Should use painlessMesh time sync for accurate ISO 8601 timestamps
   • Location: getISO8601Timestamp() in both reporter and publisher

2. Multi-Hop Routing

   • getHopCount() currently simplified (1 for direct, 2 for indirect)
   • Need proper BFS traversal of mesh tree
   • getRoutingTable() only shows direct connections

3. Node Status from Messages

   • Currently using placeholder values for non-gateway nodes
   • Should parse StatusPackage messages to get actual uptime, memory, firmware
   • Store in cache indexed by node ID

4. Throughput Tracking

   • calculateThroughput() returns placeholder value
   • Need to track messages per second over time window
   • Add to Connection class metrics

5. Network Partition Detection

   • publishNetworkSplit() has TODO for partition detection
   • Need algorithm to detect when mesh splits into segments

6. Connection State Machine

   • Track connection state changes for publishConnectionRestored()
   • Need to distinguish between first connect and reconnect

Unit Tests (catch2):

• ✅ Command response tracking (already exists)
• ✅ Status package serialization (already exists)
• ⏳ Topology JSON schema validation (TODO)
• ⏳ Event JSON schema validation (TODO)

Integration Tests (hardware):

• ⏳ 3-node mesh topology (TODO)
• ⏳ Node join/leave events (TODO)
• ⏳ Connection quality metrics (TODO)
• ⏳ Full/incremental updates (TODO)

Manual Tests:

• ⏳ MQTT message inspection
• ⏳ Web dashboard visualization (D3.js)
• ⏳ Schema validation with ajv

1. Update mqttCommandBridge.ino - Integrate topology reporter and event publisher
2. Test compilation - Ensure no errors with new API methods
3. Manual MQTT inspection - Subscribe to topics and verify JSON structure

4. Add GET_TOPOLOGY command - Command 300 handler
5. Create hardware test sketch - 3-node mesh validation
6. Fix NTP timestamps - Use painlessMesh time sync

7. Schema validation tests - Automated JSON schema checks
8. Documentation updates - MQTT_BRIDGE_COMMANDS.md and MESH_TOPOLOGY_GUIDE.md
9. Multi-hop routing - Proper hop count calculation
10. Node status caching - Track actual node metrics from status messages

• ✅ src/painlessmesh/mesh.hpp - Added ConnectionInfo, API methods, Connection metrics

• ✅ examples/bridge/mesh_topology_reporter.hpp - Topology reporter class
• ✅ examples/bridge/mesh_event_publisher.hpp - Event publisher class
• ✅ docs/IMPLEMENTATION_PLAN_MESH_TOPOLOGY.md - Implementation plan
• ✅ docs/MQTT_SCHEMA_REVIEW.md - Schema review and recommendations (already existed)
• ✅ THIS FILE - Progress tracking

• ⏳ examples/mqttCommandBridge/mqttCommandBridge.ino - Integrate reporters
• ⏳ examples/bridge/mqtt_command_bridge.hpp - Add command 300
• ⏳ docs/MQTT_BRIDGE_COMMANDS.md - Add topology docs
• ⏳ test/catch/catch_topology_schema.cpp - Add schema tests (new file)
• ⏳ examples/mqttTopologyTest/mqttTopologyTest.ino - Hardware test (new file)
• ⏳ docs/MESH_TOPOLOGY_GUIDE.md - Visualization guide (new file)

⏳ Not Yet Tested - Need to compile after integration

Expected issues:

• None (API changes are additive, backward compatible)

⏳ Not Yet Run - Integration pending

✅ Last CI Build: Passed (commit 81ba4bc - CI fixes)

Efficiency Note: Implementation is progressing faster than estimated due to:

• Clear implementation plan (IMPLEMENTATION_PLAN_MESH_TOPOLOGY.md)
• Well-defined schemas (MQTT_SCHEMA_REVIEW.md)
• Existing infrastructure (MqttCommandBridge, StatusPackage)

• Core API additions (backward compatible)
• New classes (no changes to existing code)
• Schema-compliant JSON generation

• Platform-specific RSSI (needs ESP32/ESP8266 testing)
• Memory usage (8KB JSON buffers on ESP8266)
• NTP timestamp integration

• None identified at this stage

1. Mesh ID Convention

   • Currently hardcoded as "MESH-001"
   • Should this be configurable?
   • Should it be derived from gateway node ID?

2. Firmware Version

   • Currently hardcoded as "GW 2.3.4"
   • Should this come from library version?
   • Should it be user-defined in setup()?

3. Node Role Detection

   • Currently assumes all non-gateway nodes are "sensor"
   • How to distinguish sensor vs repeater vs bridge?
   • Should nodes self-report their role?

4. Topology Publish Frequency

   • Full: Every 60 seconds
   • Incremental: Every 5 seconds (if changed)
   • Are these intervals appropriate?
   • Should they be configurable?

Updated: October 12, 2025 15:30 UTC
Next Update: After Phase 3 integration complete