node.js - 意图处理程序失败并出现错误：未定义缓冲区

问题描述

如以下文章中所述，我使用 Local Fulfillment SDK 构建了 Google Smart Home Action：

我正在使用 UDP 进行设备发现，我的 Google Nest Hub 可以成功扫描和检测在我的笔记本电脑上运行的虚拟设备以及下载本地应用程序的 JS。

我的本地家庭 SDK 配置如下 -本地家庭 SDK 配置。

当 Nest Hub 执行我的应用处理程序的 IDENTIFY 意图时，我收到以下错误：

[smarthome.DeviceManager] Intent handler failed with error: Buffer is not defined

[smarthome.DeviceManager] Got a rejected promise Buffer is not defined

这似乎是一个 Node.JS 错误，而不是特定于本地 SDK 应用程序本身的错误。以下是我本地应用程序的代码。

/// <reference types="@google/local-home-sdk" />

import App = smarthome.App;
import Constants = smarthome.Constants;
import DataFlow = smarthome.DataFlow;
import Execute = smarthome.Execute;
import Intents = smarthome.Intents;
import IntentFlow = smarthome.IntentFlow;

const SERVER_PORT = 3388;

interface ILightParams {
  on?: boolean,
  brightness?: number
}

class LocalExecutionApp {

  constructor(private readonly app: App) { }

  identifyHandler(request: IntentFlow.IdentifyRequest):
      Promise<IntentFlow.IdentifyResponse> {
    console.log("IDENTIFY intent: " + JSON.stringify(request, null, 2));

    const scanData = request.inputs[0].payload.device.udpScanData;
    console.log("SCANDATA: " + JSON.stringify(scanData));
    if (!scanData) {
      const err = new IntentFlow.HandlerError(request.requestId, 'invalid_request', 'Invalid scan data');
      return Promise.reject(err);
    }

    const localDeviceId = Buffer.from(scanData.data, 'hex');
    console.log("ScanData Local Device: " + localDeviceId);

    const response: IntentFlow.IdentifyResponse = {
      intent: Intents.IDENTIFY,
      requestId: request.requestId,
      payload: {
        device: {
          // id: localDeviceId.toString(),
          id: 'sample-device',
          verificationId: localDeviceId.toString(),
        }
      }
    };
    console.log("IDENTIFY response: " + JSON.stringify(response, null, 2));

    return Promise.resolve(response);
  }

  executeHandler(request: IntentFlow.ExecuteRequest):
      Promise<IntentFlow.ExecuteResponse> {
    console.log("EXECUTE intent: " + JSON.stringify(request, null, 2));

    const command = request.inputs[0].payload.commands[0];
    const execution = command.execution[0];
    const response = new Execute.Response.Builder()
      .setRequestId(request.requestId);

    const promises: Promise<void>[] = command.devices.map((device) => {
      console.log("Handling EXECUTE intent for device: " + JSON.stringify(device));

      // Convert execution params to a string for the local device
      const params = execution.params as ILightParams;
      const payload = this.getDataForCommand(execution.command, params);

      // Create a command to send over the local network
      const radioCommand = new DataFlow.HttpRequestData();
      radioCommand.requestId = request.requestId;
      radioCommand.deviceId = device.id;
      radioCommand.data = JSON.stringify(payload);
      radioCommand.dataType = 'application/json';
      radioCommand.port = SERVER_PORT;
      radioCommand.method = Constants.HttpOperation.POST;
      radioCommand.isSecure = false;

      console.log("Sending HTTP request to the smart home device:", payload);

      return this.app.getDeviceManager()
        .send(radioCommand)
        .then(() => {
          const state = {online: true};
          response.setSuccessState(device.id, Object.assign(state, params));
          console.log(`Command successfully sent to ${device.id}`);
        })
        .catch((e: IntentFlow.HandlerError) => {
          e.errorCode = e.errorCode || 'invalid_request';
          response.setErrorState(device.id, e.errorCode);
          console.error('An error occurred sending the command', e.errorCode);
        });
    });

    return Promise.all(promises)
      .then(() => {
        return response.build();
      })
      .catch((e) => {
        const err = new IntentFlow.HandlerError(request.requestId, 'invalid_request', e.message);
        return Promise.reject(err);
      });
  }

  /**
   * Convert execution request into a local device command
   */
  getDataForCommand(command: string, params: ILightParams): unknown {
    switch (command) {
      case 'action.devices.commands.OnOff':
        return {
          on: params.on ? true : false
        };
      default:
        console.error('Unknown command', command);
        return {};
    }
  }
}

const localHomeSdk = new App('1.0.0');
const localApp = new LocalExecutionApp(localHomeSdk);
localHomeSdk
  .onIdentify(localApp.identifyHandler.bind(localApp))
  .onExecute(localApp.executeHandler.bind(localApp))
  .listen()
  .then(() => console.log('Ready'))
  .catch((e: Error) => console.error(e));

非常感谢您对为什么会发生此错误的任何见解。

干杯。

标签： node.jsiotactions-on-googlegoogle-assistant-sdkgoogle-smart-home

在评论中重新发布答案：

Buffer不是浏览器环境直接支持的类型。您可以通过尝试x = new Buffer()在 Web 浏览器的开发控制台中运行类似的东西来亲眼看到这一点。

要支持类似的类Buffer，您可以使用 Webpack 之类的捆绑工具。在官方示例中，您可以看到一个示例 Webpack 配置。也可以使用其他的捆绑工具，示例可以在官方的Local Home脚手架工具中找到，也可以直接用npm init命令调用。

npm init @google/local-home-app app/ --bundler webpack
npm init @google/local-home-app app/ --bundler rollup
npm init @google/local-home-app app/ --bundler parcel

node.js - 意图处理程序失败并出现错误：未定义缓冲区

问题描述

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