Create connection

As explained before, each USB device can have multiple interfaces for different functions, and each interface needs to be exclusively claimed by programs.

Requesting permission to access a device doesn't automatically claim its interfaces. The connect method does that, but not only that. It includes three steps to simplify the usage:

1. Call WebUSB USBDevice#open method to open the device
2. Call WebUSB USBDevice#claimInterface method to claim the ADB interface
3. Find the endpoints for the ADB interface and create streams for them

It returns a pair of streams, one for sending and one for receiving ADB packets.

JavaScript

const connection = await device.connect();
export {};

TypeScript

import type { AdbPacketData, AdbPacketInit } from "@yume-chan/adb";
import type { Consumable, ReadableWritablePair } from "@yume-chan/stream-extra";

const connection: ReadableWritablePair<
  AdbPacketData,
  Consumable<AdbPacketInit>
> = await device.connect();

If the interface is already claimed by another program (or another USBDevice instance), connect will throw an DeviceBusyError. You can catch it and show a message to the user to ask them to close the conflicting program.

JavaScript

import { AdbDaemonWebUsbDevice } from "@yume-chan/adb-daemon-webusb";

function connect(device) {
  try {
    return await device.connect();
  } catch (error) {
    if (error instanceof AdbDaemonWebUsbDevice.DeviceBusyError) {
      alert(
        "The device is already in use by another program. Please close the program and try again.",
      );
    }
    // It might also throw other errors
    throw error;
  }
}

TypeScript

import { AdbDaemonWebUsbDevice } from "@yume-chan/adb-daemon-webusb";

function connect(device: AdbDaemonWebUsbDevice) {
  try {
    return await device.connect();
  } catch (error) {
    if (error instanceof AdbDaemonWebUsbDevice.DeviceBusyError) {
      alert(
        "The device is already in use by another program. Please close the program and try again.",
      );
    }
    // It might also throw other errors
    throw error;
  }
}

Next Step

Create credential store