@keystonehq/hw-transport-usb

Features

This package provides implementations for both WebUSB and NodeUSB drivers.and,this NPM package offers the TransportWebUSB class, which handles WebUSB functionality for Keystone hardware wallets. It also includes a TransportNodeUSB class for using USB drivers in a Node.js environment.

TransportUsbDriver Interface

This interface lays out some basic methods for USB drivers, like send, receive, open, and close. Both TransportWebUSB and TransportNodeUSB implement this interface, so they've got all these methods covered.

TransportWebUSB 和 TransportNodeUSB Class

The TransportWebUSB class takes a USB device and an optional configuration object during initialization. The TransportNodeUSB class is implemented based on the nodeusb library(https://github.com/node-usb/node-usb).

Both of these classes maintain the same API interface, so it's easy to switch between them.

The class offers two key static methods:

requestPermission

This asynchronous method requests user permission to access a USB device. It first verifies if the WebUSB API is supported in the current environment, then requests access to a USB device. After the device access permission is granted, it ensures the device is properly closed.

connect

This asynchronous method connects to a USB device. It checks for WebUSB API support in the current environment and retrieves a list of all USB devices that the application has permission to access. If multiple devices are available, the method prompts the user to select one. It then creates and returns a new TransportWebUSB instance using the selected device and the provided configuration.

TransportConfig

The TransportConfig object is an optional parameter during the initialization of the TransportWebUSB class. It enables developers to customize various settings related to the transport operation:

• endpoint: (Optional) Specifies the endpoint for the USB communication.
• timeout: (Optional) Determines the maximum duration (in milliseconds) that the transport operation should wait before timing out.
• maxPacketSize: (Optional) Defines the maximum packet size that the transport operation can handle.
• disconnectListener: (Optional) A function that is invoked when the USB device is disconnected. This function should accept a USBDevice object as an argument, representing the device that has been disconnected.

Additional Documentation

For more information, you can refer to the following documents:

• Transport Result Status Codes
• EAPDU Protocol Documentation