func (db *DB) PutRFMessage(m gears.RFMessage) error {
if m.At == 0 {
// Add the time in milliseconds since the epoch
m.At = time.Now().UnixNano() / 1000000
}
glog.V(2).Infof("Put: %d %+v", m.At, m)
// Form the key
key := genRFKey(m.At)
// Write data
err := db.Put(key, m)
if err != nil {
return err
}
// Publish to subscribers
db.RFPublish(m)
return nil
}
// Receive UDP packets, decode them, and output them
// The packet format is (by byte): flags, group, node_id, kind, data...
func (u *UDPGateway) Receiver() {
for {
glog.V(2).Infoln("******************************")
pkt := make([]byte, 1600)
pktLen, pktSrc, err := u.sock.ReadFromUDP(pkt)
if err != nil {
glog.Warning("UDP error: " + err.Error())
continue
}
if pktLen < 3 {
glog.Infof("UDP: got too short a packet (%d) from %v", pktLen, pktSrc)
continue
}
if pktLen > 66+3 {
glog.Infof("UDP: got too long a packet (%d) from %v", pktLen, pktSrc)
continue
}
// got a reasonable packet
data := pkt[0:pktLen]
flags := data[0]
groupId := data[1]
nodeId := data[2]
// Record the groupId -> addr mapping
_ = u.groupMap.saveGroupToAddr(groupId, pktSrc)
switch flags {
// CTL + ACK + DST -> boot protocol pairing request
// I.e: a node sends us its HW ID and we reply with groupId/nodeId/nodeType
case 8:
u.handlePairingRequest(pktSrc, groupId, nodeId, data)
// CTL + ACK -> boot protocol upgrade or download request
// I.e.: a node asks for the software Id & checksum or downloads a chunk
case 5:
switch pktLen {
case UpgradeRequestLen + 3:
u.handleUpgradeRequest(pktSrc, groupId, nodeId, data)
case DownloadRequestLen + 3:
u.handleDownloadRequest(pktSrc, groupId, nodeId, data)
default:
glog.Warningf(" Incorrect length=%d (!= %d)",
pktLen, PairingRequestLen+3)
}
// Special packet to log from UDP GW itself
case 9:
glog.Infof("UDP-GW %d: %s", groupId, string(data[3:]))
m := gears.RFMessage{
Group: groupId,
Node: nodeId,
At: time.Now().UnixNano() / 1000000,
Kind: 2, // LOG module
Data: append([]byte("GW "), data[3:]...),
}
u.Recv <- m
// Standard data packet, produce a Message
case 0, 1:
m := gears.RFMessage{
Group: groupId,
Node: nodeId,
At: time.Now().UnixNano() / 1000000,
}
if nodeId == 31 && len(m.Data)&1 == 0 {
// hack to handle the fact that the early versions of the UDP GW node
// don't use a _kind_ byte in the messages
m.Kind = 8 // GW_RSSI_MODULE
m.Data = data[3:]
} else if pktLen > 3 {
m.Kind = data[3]
m.Data = data[4:]
} else {
m.Data = data[3:]
}
glog.Infof("UDP Recv: %s len=%d", m.RfTag(), pktLen)
glog.V(4).Infof(" src=%v Pkt=%+v", pktSrc, m.Data[0:min(len(m.Data), 10)])
// If an ACK is requested we should send that asap
if flags&1 != 0 {
u.sendPacket(groupId, nodeId, 0x6, []byte{})
}
// Now process what we got
u.Recv <- m
}
}
}