modbus-connect/transport/factory.js

Modbus RTU over Web Serial and Node.js SerialPort

// transport/factory.js

const logger = require('../logger.js');

async function createTransport(type, options = {}) {
  logger.setTransportType(type);

  try {
    switch (type) {
      // Creating a Transport for the Node.js Environment
      case 'node': {
        const path = options.port || options.path;
        if (!path) {
          throw new Error('Missing "port" (or "path") option for node transport');
        }
        const { NodeSerialTransport } = await import('./node-serialport.js');
        const rest = { ...options };
        delete rest.port;
        delete rest.path;
        return new NodeSerialTransport(path, rest);
      }

      // Creating a Transport for the Web Environment
      case 'web': {
        if (!options.port) {
          throw new Error('Missing "port" option for web transport');
        }
        const { WebSerialTransport } = await import('./web-serialport.js');
        const portInstance = options.port;
        const rest = { ...options };
        delete rest.port;
        return new WebSerialTransport(portInstance, rest);
      }

      // Creating a TCP Transport for the Node Environment
      case 'tcp': {
        const { TcpSerialTransport } = await import('./tcp-serialport.js');
        const host = options.host;
        if (!host) {
          throw new Error('Missing "host" option for tcp transport');
        }
        const rest = { ...options };
        delete rest.host;
        return new TcpSerialTransport(host, rest);
      }

      // Unknown or unsupported type
      default:
        throw new Error(`Unknown transport type: ${type}`);
    }
  } catch (err) {
    logger.error(`Failed to create transport of type "${type}": ${err.message}`);
    throw err;
  }
}

module.exports = {
  createTransport
}