解码功能完成

README.md

@@ -0,0 +1,93 @@
+# Meshtastic MQTT Server
+
+这是一个 Meshtastic MQTT 订阅工具，用 Go 实现 [py/mqtt_nodeinfo_subscriber.py](py/mqtt_nodeinfo_subscriber.py) 的主要功能。
+
+程序会连接 Meshtastic MQTT broker，订阅指定 topic，解析 `ServiceEnvelope` / `MeshPacket`，并将重点数据包以 JSONL 形式输出到控制台。
+
+## 运行
+
+```bash
+go run .
+```
+
+默认连接：
+
+- broker：`mqtt.meshtastic.org:1883`
+- username：`meshdev`
+- password：`large4cats`
+- topic：`msh/US/#`
+- PSK：`AQ==`
+
+也可以指定 topic：
+
+```bash
+go run . --topic 'msh/US/#'
+```
+
+多个 topic 可重复传入：
+
+```bash
+go run . --topic 'msh/US/#' --topic 'msh/EU_868/#'
+```
+
+## 参数
+
+```text
+--host       MQTT broker hostname
+--port       MQTT broker port
+--username   MQTT username
+--password   MQTT password
+--psk        Base64 channel PSK used to try decrypting encrypted packets
+--topic      Topic to subscribe; may be repeated
+--qos        MQTT subscription QoS: 0, 1, or 2
+--client-id  MQTT client id
+```
+
+## 控制台颜色说明
+
+程序会按数据包类型使用不同背景色，方便快速区分消息类型。
+
+| 背景色 | type | portnum | 含义 |
+|---|---|---|---|
+| 绿色 | `nodeinfo` | `NODEINFO_APP` | 节点信息包，包含节点 ID、长名称、短名称、硬件型号、角色、公钥等 |
+| 蓝色 | `map_report` | `MAP_REPORT_APP` | 地图报告包，包含节点名称、硬件、固件版本、区域、调制预设、位置等地图信息 |
+| 紫色 | `text_message` | `TEXT_MESSAGE_APP` | 聊天文本消息 |
+| 青色 | `position` | `POSITION_APP` | 位置包，表示节点位置相关数据；当前只标记类型，不展开解析 payload |
+| 黄色 | `telemetry` | `TELEMETRY_APP` | 遥测包，表示电池、信道、设备或环境传感器相关数据；当前只标记类型，不展开解析 payload |
+| 灰色 | `routing` | `ROUTING_APP` | 路由控制包，常见于 ACK、NAK、路由错误等控制信息 |
+| 灰色 | `traceroute` | `TRACEROUTE_APP` | 路径追踪包，用于 mesh 网络路径探测 |
+| 红色 | error record | - | protobuf 解析失败、payload 解码失败或其他处理错误 |
+| 无颜色 | `encrypted_packet` | - | 加密包但当前 PSK/频道 hash 无法解密；这不一定是错误 |
+| 无颜色 | `decoded_packet` | 其他 portnum | 已解码/已解密，但程序尚未细分的其他应用包 |
+
+## 过滤规则
+
+程序默认不显示 `empty_packet`。
+
+`empty_packet` 指 `MeshPacket` 中没有 `decoded` 或 `encrypted` payload 的包，只包含类似 `from`、`to`、`id`、`via_mqtt` 等包头信息。根据固件源码分析，这类包通常不是普通业务数据，更多是 MQTT 回显/隐式 ACK 相关的元信息，对查看节点信息、地图报告和聊天内容价值较低。
+
+## 输出示例
+
+节点信息包：
+
+```json
+{"type":"nodeinfo","portnum":"NODEINFO_APP","from":"!a8dfd867","long_name":"Kabi Matrix 🖥️","short_name":"KaMX","hw_model":"PRIVATE_HW","role":"CLIENT_MUTE"}
+```
+
+地图报告包：
+
+```json
+{"type":"map_report","portnum":"MAP_REPORT_APP","from":"!675c9803","long_name":"PaulHome","latitude":42.51043,"longitude":-83.08624999999999,"hw_model":"PORTDUINO"}
+```
+
+聊天消息包：
+
+```json
+{"type":"text_message","portnum":"TEXT_MESSAGE_APP","from":"!12345678","text":"hello mesh"}
+```
+
+解密失败的加密包：
+
+```json
+{"type":"encrypted_packet","decrypt_success":false,"decrypt_status":"channel hash mismatch","encrypted_len":43}
+```

main.go

@@ -13,6 +13,7 @@ import (
 	"os/signal"
 	"syscall"
 	"time"
+	"unicode/utf8"
 
 	mqtt "github.com/eclipse/paho.mqtt.golang"
 	"google.golang.org/protobuf/encoding/protowire"
@@ -27,11 +28,20 @@ const (
 
 	ansiGreenBGWhiteText  = "\033[42;37m"
 	ansiBlueBGWhiteText   = "\033[44;37m"
+	ansiPurpleBGWhiteText = "\033[45;37m"
+	ansiCyanBGBlackText   = "\033[46;30m"
+	ansiYellowBGBlackText = "\033[43;30m"
+	ansiGrayBGWhiteText   = "\033[100;37m"
 	ansiRedBGWhiteText    = "\033[41;37m"
 	ansiReset             = "\033[0m"
 
 	unknownApp     = 0
+	textMessageApp = 1
+	positionApp    = 3
 	nodeInfoApp    = 4
+	routingApp     = 5
+	telemetryApp   = 67
+	tracerouteApp  = 70
 	mapReportApp   = 73
 )
 
@@ -205,6 +215,9 @@ func handleMessage(key []byte) mqtt.MessageHandler {
 			printJSON(map[string]any{"topic": msg.Topic(), "error": err.Error(), "payload_len": len(msg.Payload())})
 			return
 		}
+		if record["type"] == "empty_packet" {
+			return
+		}
 		printJSON(record)
 	}
 }
@@ -511,6 +524,16 @@ func describePacket(topic string, env *serviceEnvelope, key []byte) (map[string]
 			return nil, err
 		}
 		return merge(decodedBase, record), nil
+	case textMessageApp:
+		return merge(decodedBase, decodeTextMessage(packet)), nil
+	case positionApp:
+		return merge(decodedBase, map[string]any{"type": "position"}), nil
+	case telemetryApp:
+		return merge(decodedBase, map[string]any{"type": "telemetry"}), nil
+	case routingApp:
+		return merge(decodedBase, map[string]any{"type": "routing"}), nil
+	case tracerouteApp:
+		return merge(decodedBase, map[string]any{"type": "traceroute"}), nil
 	default:
 		return merge(decodedBase, map[string]any{"type": "decoded_packet"}), nil
 	}
@@ -602,6 +625,21 @@ func decodeMapReport(packet *meshPacket) (map[string]any, error) {
 	}, nil
 }
 
+func decodeTextMessage(packet *meshPacket) map[string]any {
+	text := string(packet.Decoded.Payload)
+	record := map[string]any{
+		"type":     "text_message",
+		"from":     nodeNumToID(packet.From),
+		"from_num": packet.From,
+		"text":     text,
+	}
+	if !utf8.Valid(packet.Decoded.Payload) {
+		record["text"] = nil
+		record["payload_hex"] = hex.EncodeToString(packet.Decoded.Payload)
+	}
+	return record
+}
+
 func merge(base map[string]any, extra map[string]any) map[string]any {
 	out := make(map[string]any, len(base)+len(extra))
 	for k, v := range base {
@@ -619,14 +657,24 @@ func printJSON(record map[string]any) {
 		text, _ = json.Marshal(map[string]any{"error": err.Error()})
 	}
 
-	switch {
+	switch record["type"] {
-	case record["decrypt_success"] == true:
+	case "nodeinfo":
 		fmt.Printf("%s%s%s\n", ansiGreenBGWhiteText, text, ansiReset)
-	case record["error"] != nil:
+	case "map_report":
-		fmt.Printf("%s%s%s\n", ansiRedBGWhiteText, text, ansiReset)
-	case record["type"] == "decoded_packet":
 		fmt.Printf("%s%s%s\n", ansiBlueBGWhiteText, text, ansiReset)
+	case "text_message":
+		fmt.Printf("%s%s%s\n", ansiPurpleBGWhiteText, text, ansiReset)
+	case "position":
+		fmt.Printf("%s%s%s\n", ansiCyanBGBlackText, text, ansiReset)
+	case "telemetry":
+		fmt.Printf("%s%s%s\n", ansiYellowBGBlackText, text, ansiReset)
+	case "routing", "traceroute":
+		fmt.Printf("%s%s%s\n", ansiGrayBGWhiteText, text, ansiReset)
 	default:
+		if record["error"] != nil {
+			fmt.Printf("%s%s%s\n", ansiRedBGWhiteText, text, ansiReset)
+			return
+		}
 		fmt.Println(string(text))
 	}
 }