Fixes#276
## Root cause
TRACE packets store hop IDs in the payload (bytes 9+) rather than in the
header path field. The header path field is overloaded in TRACE packets
to carry RSSI values instead of repeater IDs (as noted in the issue
comments). This meant `Path.Hops` was always empty for TRACE packets —
the raw bytes ended up as an opaque `PathData` hex string with no
structure.
The hashSize encoded in the header path byte (bits 6–7) is still valid
for TRACE and is used to split the payload path bytes into individual
hop prefixes.
## Fix
After decoding a TRACE payload, if `PathData` is non-empty, parse it
into individual hops using `path.HashSize`:
```go
if header.PayloadType == PayloadTRACE && payload.PathData != "" {
pathBytes, err := hex.DecodeString(payload.PathData)
if err == nil && path.HashSize > 0 {
for i := 0; i+path.HashSize <= len(pathBytes); i += path.HashSize {
path.Hops = append(path.Hops, ...)
}
}
}
```
Applied to both `cmd/ingestor/decoder.go` and `cmd/server/decoder.go`.
## Verification
Packet from the issue: `260001807dca00000000007d547d`
| | Before | After |
|---|---|---|
| `Path.Hops` | `[]` | `["7D", "54", "7D"]` |
| `Path.HashCount` | `0` | `3` |
New test `TestDecodeTracePathParsing` covers this exact packet.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Match the C++ firmware wire format (Packet::writeTo/readFrom):
1. Field order: transport codes are parsed BEFORE path_length byte,
matching firmware's header → transport_codes → path_len → path → payload
2. ACK payload: just 4-byte CRC checksum, not dest+src+ackHash.
Firmware createAck() writes only ack_crc (4 bytes).
3. TRACE payload: tag(4) + authCode(4) + flags(1) + pathData,
matching firmware createTrace() and onRecvPacket() TRACE handler.
4. ADVERT features: parse feat1 (0x20) and feat2 (0x40) optional
2-byte fields between location and name, matching AdvertDataBuilder
and AdvertDataParser in the firmware.
5. Transport code naming: code1/code2 instead of nextHop/lastHop,
matching firmware's transport_codes[0]/transport_codes[1] naming.
Fixes applied to both cmd/ingestor/decoder.go and cmd/server/decoder.go.
Tests updated to match new behavior.
#184: Strip non-printable chars (<0x20 except tab/newline) from ADVERT
names in Go server decoder, Go ingestor decoder, and Node decoder.js.
#185: Add visual (N) badge next to node names when multiple nodes share
the same display name (case-insensitive). Shows in list, side pane, and
full detail page with 'also known as' links to other keys.
#186: Add packetsLast24h field to /api/stats response.
#187#188: Cache runtime.ReadMemStats() with 5s TTL in Go server.
#189: Temporarily patch HTMLCanvasElement.prototype.getContext during
L.heatLayer().addTo(map) to pass { willReadFrequently: true }, preventing
Chrome console warning about canvas readback performance.
Tests: 10 new tests for buildDupNameMap + dupNameBadge (143 total frontend).
Cache busters bumped.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
