Initial commit: NestJS meshtastic bridge bot

2026-09-23 17:36:11 +00:00
commit 83e46b8f07
21 changed files with 6248 additions and 0 deletions
@@ -0,0 +1,124 @@
+import {
+  Injectable,
+  Logger,
+  OnModuleDestroy,
+  OnModuleInit,
+  ServiceUnavailableException,
+} from '@nestjs/common';
+import * as net from 'node:net';
+import {
+  PORT_TEXT_MESSAGE_APP,
+  buildTextToRadio,
+  decodeFromRadio,
+  extractFrames,
+} from './codec.js';
+
+@Injectable()
+export class MeshService implements OnModuleInit, OnModuleDestroy {
+  private readonly logger = new Logger(MeshService.name);
+  private readonly host = process.env.MESH_HOST ?? '192.168.1.4';
+  private readonly port = parseInt(process.env.MESH_PORT ?? '4003', 10);
+
+  private socket: net.Socket | null = null;
+  private buffer: Uint8Array = new Uint8Array(0);
+  private connected = false;
+  private myNodeNum: number | null = null;
+  private reconnectTimer: NodeJS.Timeout | null = null;
+  private shuttingDown = false;
+
+  onModuleInit(): void {
+    this.connect();
+  }
+
+  onModuleDestroy(): void {
+    this.shuttingDown = true;
+    if (this.reconnectTimer) clearTimeout(this.reconnectTimer);
+    this.socket?.destroy();
+  }
+
+  status() {
+    return {
+      connected: this.connected,
+      myNodeNum: this.myNodeNum,
+      host: this.host,
+      port: this.port,
+    };
+  }
+
+  async sendText(to: number, text: string): Promise<number> {
+    if (!this.connected || !this.socket)
+      throw new ServiceUnavailableException('bridge not connected');
+    const { bytes, id } = await buildTextToRadio(to, text);
+    this.socket.write(bytes);
+    return id;
+  }
+
+  private connect(): void {
+    if (this.shuttingDown) return;
+    const socket = net.createConnection({ host: this.host, port: this.port });
+    this.socket = socket;
+    socket.on('connect', () => {
+      this.connected = true;
+      this.logger.log(`bridge connected ${this.host}:${this.port}`);
+    });
+    socket.on('data', (chunk) => {
+      const merged = new Uint8Array(this.buffer.length + chunk.length);
+      merged.set(this.buffer, 0);
+      merged.set(chunk, this.buffer.length);
+      this.buffer = merged;
+      const { packets, rest } = extractFrames(this.buffer);
+      this.buffer = rest;
+      for (const p of packets) {
+        decodeFromRadio(p)
+          .then((fr) => this.handleFromRadio(fr))
+          .catch((err: unknown) =>
+            this.logger.error(`decode failed: ${String(err)}`),
+          );
+      }
+    });
+    const onDown = () => {
+      this.connected = false;
+      this.scheduleReconnect();
+    };
+    socket.on('error', (err) => {
+      this.logger.warn(`bridge error: ${err.message}`);
+      onDown();
+    });
+    socket.on('close', onDown);
+  }
+
+  private scheduleReconnect(): void {
+    if (this.shuttingDown) return;
+    if (this.reconnectTimer) clearTimeout(this.reconnectTimer);
+    // ponytail: fixed 5s retry, no backoff — fine for single-bridge use
+    this.reconnectTimer = setTimeout(() => this.connect(), 5000);
+  }
+
+  private handleFromRadio(
+    fr: import('@meshtastic/protobufs').Mesh.FromRadio,
+  ): void {
+    const v = fr.payloadVariant;
+    switch (v?.case) {
+      case 'myInfo':
+        this.myNodeNum = v.value.myNodeNum;
+        this.logger.log(`my node num: ${this.myNodeNum}`);
+        break;
+      case 'configCompleteId':
+        this.logger.log('bridge ready (config complete)');
+        break;
+      case 'packet': {
+        const pkt = v.value;
+        const decoded =
+          pkt.payloadVariant?.case === 'decoded'
+            ? pkt.payloadVariant.value
+            : undefined;
+        if (decoded && decoded.portnum === PORT_TEXT_MESSAGE_APP) {
+          this.logger.log(
+            `[mesh] ${pkt.from} -> ${pkt.to}: "${new TextDecoder().decode(decoded.payload)}"`,
+          );
+        }
+        break;
+      }
+    }
+  }
+}