How to use @ledgerhq/devices - 10 common examples

if (e.errorCode === BleErrorCode.DeviceMTUChangeFailed) {
        // eslint-disable-next-line require-atomic-updates
        connectOptions = {};
        await device.connect();
      } else {
        throw e;
      }
    }
  }

  await device.discoverAllServicesAndCharacteristics();

  let res = retrieveInfos(device);
  let characteristics;
  if (!res) {
    for (const uuid of getBluetoothServiceUuids()) {
      try {
        characteristics = await device.characteristicsForService(uuid);
        res = getInfosForServiceUuid(uuid);
        break;
      } catch (e) {
        // we attempt to connect to service
      }
    }
  }
  if (!res) {
    throw new TransportError("service not found", "BLEServiceNotFound");
  }

  const { deviceModel, serviceUuid, writeUuid, notifyUuid } = res;

  if (!characteristics) {

}

    log("ble-verbose", `open(${deviceOrId})`);

    await awaitsBleOn(bleManager);

    if (!device) {
      // works for iOS but not Android
      const devices = await bleManager.devices([deviceOrId]);
      log("ble-verbose", `found ${devices.length} devices`);
      [device] = devices;
    }

    if (!device) {
      const connectedDevices = await bleManager.connectedDevices(
        getBluetoothServiceUuids()
      );
      const connectedDevicesFiltered = connectedDevices.filter(
        d => d.id === deviceOrId
      );
      log(
        "ble-verbose",
        `found ${connectedDevicesFiltered.length} connected devices`
      );
      [device] = connectedDevicesFiltered;
    }

    if (!device) {
      log("ble-verbose", `connectToDevice(${deviceOrId})`);
      try {
        device = await bleManager.connectToDevice(deviceOrId, connectOptions);
      } catch (e) {

await device.connect();
      } else {
        throw e;
      }
    }
  }

  await device.discoverAllServicesAndCharacteristics();

  let res = retrieveInfos(device);
  let characteristics;
  if (!res) {
    for (const uuid of getBluetoothServiceUuids()) {
      try {
        characteristics = await device.characteristicsForService(uuid);
        res = getInfosForServiceUuid(uuid);
        break;
      } catch (e) {
        // we attempt to connect to service
      }
    }
  }
  if (!res) {
    throw new TransportError("service not found", "BLEServiceNotFound");
  }

  const { deviceModel, serviceUuid, writeUuid, notifyUuid } = res;

  if (!characteristics) {
    characteristics = await device.characteristicsForService(serviceUuid);
  }

this.exchangeAtomicImpl(async () => {
      try {
        const msgIn = apdu.toString("hex");
        log("apdu", `=> ${msgIn}`);

        const data = await merge(
          this.notifyObservable.pipe(receiveAPDU),
          sendAPDU(this.write, apdu, this.mtuSize)
        ).toPromise();

        const msgOut = data.toString("hex");
        log("apdu", `<= ${msgOut}`);

        return data;
      } catch (e) {
        log("ble-error", "exchange got " + String(e));
        if (this.notYetDisconnected) {
          // in such case we will always disconnect because something is bad.
          this.device.gatt.disconnect();
        }
        throw e;
      }
    });

this.exchangeAtomicImpl(async () => {
      try {
        const msgIn = apdu.toString("hex");
        log("apdu", `=> ${msgIn}`);

        const data = await merge(
          this.notifyObservable.pipe(receiveAPDU),
          sendAPDU(this.write, apdu, this.mtuSize)
        ).toPromise();

        const msgOut = data.toString("hex");
        log("apdu", `<= ${msgOut}`);

        return data;
      } catch (e) {
        log("ble-error", "exchange got " + String(e));
        if (this.notYetDisconnected) {
          // in such case we will always disconnect because something is bad.
          await bleManager.cancelDeviceConnection(this.id).catch(() => {}); // but we ignore if disconnect worked.
        }
        throw remapError(e);
      }
    });

this.exchangeAtomicImpl(async () => {
      try {
        const msgIn = apdu.toString("hex");
        log("apdu", `=> ${msgIn}`);

        const data = await merge(
          this.notifyObservable.pipe(receiveAPDU),
          sendAPDU(this.write, apdu, this.mtuSize)
        ).toPromise();

        const msgOut = data.toString("hex");
        log("apdu", `<= ${msgOut}`);

        return data;
      } catch (e) {
        log("ble-error", "exchange got " + String(e));
        if (this.notYetDisconnected) {
          // in such case we will always disconnect because something is bad.
          await disconnectDevice(this.device).catch(() => {}); // but we ignore if disconnect worked.
        }
        throw e;
      }
    });

this.exchangeAtomicImpl(async () => {
      const { channel, packetSize } = this;
      log("apdu", "=> " + apdu.toString("hex"));

      const framing = hidFraming(channel, packetSize);

      // Write...
      const blocks = framing.makeBlocks(apdu);
      for (let i = 0; i < blocks.length; i++) {
        log("hid-frame", "=> " + blocks[i].toString("hex"));
        await this.writeHID(blocks[i]);
      }

      // Read...
      let result;
      let acc;
      while (!(result = framing.getReducedResult(acc))) {
        const buffer = await this.readHID();
        log("hid-frame", "<= " + buffer.toString("hex"));
        acc = framing.reduceResponse(acc, buffer);
      }

this.exchangeAtomicImpl(async () => {
      const { channel, packetSize } = this;
      log("apdu", "=> " + apdu.toString("hex"));

      const framing = hidFraming(channel, packetSize);

      // Write...
      const blocks = framing.makeBlocks(apdu);
      for (let i = 0; i < blocks.length; i++) {
        log("hid-frame", "=> " + blocks[i].toString("hex"));
        await this.device.sendReport(0, blocks[i]);
      }

      // Read...
      let result;
      let acc;
      while (!(result = framing.getReducedResult(acc))) {
        const buffer = await this.read();
        log("hid-frame", "<= " + buffer.toString("hex"));
        acc = framing.reduceResponse(acc, buffer);
      }

this.exchangeAtomicImpl(async () => {
      const { channel, packetSize } = this;
      log("apdu", "=> " + apdu.toString("hex"));

      const framing = hidFraming(channel, packetSize);

      // Write...
      const blocks = framing.makeBlocks(apdu);
      for (let i = 0; i < blocks.length; i++) {
        log("hid-frame", "=> " + blocks[i].toString("hex"));
        await this.device.transferOut(endpointNumber, blocks[i]);
      }

      // Read...
      let result;
      let acc;
      while (!(result = framing.getReducedResult(acc))) {
        const r = await this.device.transferIn(endpointNumber, packetSize);
        const buffer = Buffer.from(r.data.buffer);
        log("hid-frame", "<= " + buffer.toString("hex"));
        acc = framing.reduceResponse(acc, buffer);

if (!navigator.credentials) {
    throw new TransportError("WebAuthn not supported", "NotSupported");
  }

  return (
    navigator.credentials
      // $FlowFixMe
      .get({
        publicKey: {
          timeout,
          challenge: new Uint8Array(32),
          allowCredentials: [
            {
              type: "public-key",
              id: new Uint8Array(wrapApdu(apdu, scrambleKey))
            }
          ]
        }
      })
      // $FlowFixMe
      .then(r => Buffer.from(r.response.signature))
  );
};