First implementation of PacketStreamFactory

src/streamHandler/PacketStreamFactory.js

@@ -0,0 +1,96 @@
+const logger = require.main.require("./helper/logger.js")("PacketStreamFactory");
+const { Transform } = require('stream');
+const { DateTime } = require("luxon");
+const { PacketType, Packet, PacketWithSSID, BeaconPacket, ProbeRequestPacket, ProbeResponsePacket } = require.main.require('./dto/Packet.js');
+
+const PACKET_TYPE_MAP = {
+    "Beacon":           PacketType.Beacon,
+    "Probe Request":    PacketType.ProbeRequest,
+    "Probe Response":   PacketType.ProbeResponse,
+    "Data":             PacketType.Data,
+    "More Data":        PacketType.MoreData,
+    "Request-To-Send":  PacketType.RequestToSend,
+    "Clear-To-Send":    PacketType.ClearToSend,
+    "Acknowledgment":   PacketType.Acknowledgment,
+    "BA":               PacketType.BlockAcknowledgment
+};
+const PACKET_TYPES_REGEX = Object.keys(PACKET_TYPE_MAP).join('|');
+
+/**
+ * Read data from text-blocks and convert them to Packet
+ */
+class PacketStreamFactory extends Transform{
+    matcher;
+    withholdLastBlock;
+    matchAllOnFlush;
+
+    constructor(){
+        super({
+            readableObjectMode: true,
+            writableObjectMode: true
+        });
+    }
+
+    _transform(chunk, encoding, next){
+        let packet = new Packet();
+
+        const lines = chunk.split('\n');
+        const header = lines.splice(0, 1)[0];       // Grab first line, 'lines' is now the payload
+        this._handleHeader(packet, header);
+        this._handlePayload(packet, lines);
+        
+        logger.debug(packet);
+
+        this.read();
+        next(null, packet);     // Get next chunk
+    }
+
+    _handleHeader(packet, data){
+        // Convert time to epoch-micros         Unfortunately luxon doesnt use micros, but millis as smallest time-unit requiring some "hacks"
+        packet.timestampMicros = DateTime.fromISO(data.slice(0, 12)).toSeconds() + data.slice(12, 15)/1000000;
+
+        packet.dataRate = Number(data.match(/(^| )([0-9]+(\.[0-9]+)?) Mb\/s($| )/i)[2]);
+        packet.frequency = Number(data.match(/(^| )([0-9]{4}) MHz($| )/i)[2]);
+
+        let signalStrMatch = data.match(/(^| )(-[0-9]{2})dBm Signal($| )/i);
+        if(signalStrMatch) packet.signal = Number(signalStrMatch[2]);
+        else packet.signal = -100;
+
+        let packetTypeStrMatch = data.match(new RegExp(`(^|.{80} )(${PACKET_TYPES_REGEX})($| )`, 'i'));
+        let packetTypeStr;
+        if(packetTypeStrMatch) {
+            packetTypeStr = packetTypeStrMatch[2];
+            packet.packetType = PACKET_TYPE_MAP[packetTypeStr];
+        }
+        else
+            packet.packetType = PacketType.Unknown;
+        
+        let srcMacMatch = data.match(/(^| )(SA|TA):(.{17})($| )/i);
+        if(srcMacMatch) packet.srcMac = srcMacMatch[3];
+
+        let dstMacMatch = data.match(/(^| )(DA|RA):(.{17})($| )/i);
+        if(dstMacMatch) packet.dstMac = dstMacMatch[3];
+        
+        let bssidMatch = data.match(/(^| )BSSID:(.{17})($| )/i)
+        if(bssidMatch) packet.bssid = bssidMatch[2];
+
+        // Cover special cases with more data
+        switch(packet.packetType){
+            case PacketType.Beacon:
+            case PacketType.ProbeRequest:
+            case PacketType.ProbeResponse:
+                packet = Object.assign(new PacketWithSSID(), packet);   // Create new, more specific, packet and copy old data over
+                packet.ssid = data.match(new RegExp(`(^| )${packetTypeStr} `+'\\'+`((.{0,32})`+'\\'+`)($| )`, 'i'))[2];
+                break;
+        }
+    }
+
+    _handlePayload(packet, data){
+        
+    }
+}
+
+// Specify exports
+module.exports = {
+    PacketStreamFactory
+};