meshastic.web/packages/transport-web-serial/src/transport.ts

import { Utils } from "@meshtastic/core";
import type { Types } from "@meshtastic/core";

export class TransportWebSerial implements Types.Transport {
  private _toDevice: WritableStream<Uint8Array>;
  private _fromDevice: ReadableStream<Types.DeviceOutput>;

  public static async create(baudRate?: number): Promise<TransportWebSerial> {
    const port = await navigator.serial.requestPort();
    await port.open({ baudRate: baudRate || 115200 });
    return new TransportWebSerial(port);
  }

  public static async createFromPort(
    port: SerialPort,
    baudRate?: number,
  ): Promise<TransportWebSerial> {
    await port.open({ baudRate: baudRate || 115200 });
    return new TransportWebSerial(port);
  }

  constructor(connection: SerialPort) {
    if (!connection.readable || !connection.writable) {
      throw new Error("Stream not accessible");
    }

    Utils.toDeviceStream.readable.pipeTo(connection.writable);

    this._toDevice = Utils.toDeviceStream.writable;
    this._fromDevice = connection.readable.pipeThrough(
      Utils.fromDeviceStream(),
    );
  }

  get toDevice(): WritableStream<Uint8Array> {
    return this._toDevice;
  }

  get fromDevice(): ReadableStream<Types.DeviceOutput> {
    return this._fromDevice;
  }
}