Alexa Skills Custom Intents中未定义对象的问题

Question

我目前正在尝试做一个Alexa的技巧，当我给alexa一个正确的提示时，它会向我的苹果设备发出一个“找到我的iPhone”的提示。我对alexa技能集的开发和编码非常陌生(特别是在node.js中)。以下是我的原话：

var phoneId = "I have my values here";
var ipadId = "I have my values here";
var macId = "I have my values here";
var deviceId = "";


var APP_ID = ''; //replace with "amzn1.echo-sdk-ams.app.[your-unique-value-here]";

var AlexaSkill = require('./AlexaSkill');
var alexaResponse;

//Import Apple.js
var Apple = require('./Apple');
var apple = new Apple();

var alertSuccess = "Alert sent to Kenny's phone";
var alertFailed = "Alert couldn't be sent to Kenny's phone. Good luck finding it.";

var FindDevice = function () {
    AlexaSkill.call(this, APP_ID);
};

// Extend AlexaSkill
FindDevice.prototype = Object.create(AlexaSkill.prototype);
FindDevice.prototype.constructor = FindDevice;

FindDevice.prototype.eventHandlers.onSessionStarted = function (sessionStartedRequest, session) {
    console.log("Quote onSessionStarted requestId: " + sessionStartedRequest.requestId
        + ", sessionId: " + session.sessionId);
    // any initialization logic goes here
};

FindDevice.prototype.eventHandlers.onLaunch = function (launchRequest, session, response) {
    console.log("Quote onLaunch requestId: " + launchRequest.requestId + ", sessionId: " + session.sessionId);
    getWelcomeResponse(response);
};

FindDevice.prototype.eventHandlers.onSessionEnded = function (sessionEndedRequest, session) {
    console.log("Quote onSessionEnded requestId: " + sessionEndedRequest.requestId
        + ", sessionId: " + session.sessionId);
    // any cleanup logic goes here
};

FindDevice.prototype.intentHandlers = {
    // register custom intent handlers
    "FindDeviceIntent": function (intent, session, response) {
        determineDevice(intent, session, response);
    }
};

/**
 * Returns the welcome response for when a user invokes this skill.
 */
function getWelcomeResponse(response) {
    // If we wanted to initialize the session to have some attributes we could add those here.
    var speechText = "Welcome to the Lost Device. Which device shall I find?";
    var repromptText = "<speak>Please choose a category by saying, " +
        "iPhone <break time=\"0.2s\" /> " +
        "Mac <break time=\"0.2s\" /> " +
        "iPad <break time=\"0.2s\" /></speak>";

    var speechOutput = {
        speech: speechText,
        type: AlexaSkill.speechOutputType.PLAIN_TEXT
    };
    var repromptOutput = {
        speech: repromptText,
        type: AlexaSkill.speechOutputType.SSML
    };
    response.ask(speechOutput, repromptOutput);
}

  function determineDevice(intent, session, response) {
    var deviceSlot = intent.slots.Device;

    if (deviceSlot == "iPhone") {
      deviceId = phoneId;
      pingDevice(deviceId);
    } else if (deviceSlot == "iPad") {
      deviceId = ipadId;
      pingDevice(deviceId);
    } else if (deviceSlot == "Mac") {
      deviceId = macId;
      pingDevice(deviceId);
    } else {
      var speechText = "None of those are valid devices. Please try again.";
      speechOutput = {
          speech: speechText,
          type: AlexaSkill.speechOutputType.PLAIN_TEXT
        };
      response.tell(speechOutput);
    }
}

  function pingDevice(deviceId) {
    apple.sendAlert(deviceId, 'Glad you found your phone.', function(success, result){
        if(success){
            console.log("Alert Sent Successfully");
            var speechOutput = alertSuccess;
            response.tell(speechOutput);
        } else {
            console.log("Alert Unsuccessful");
            console.log(result);
            var speechOutput = alertFailed;
            response.tell(speechOutput);
        }
    });
  }

// Create the handler that responds to the Alexa Request.
exports.handler = function (event, context) {
    // Create an instance of the FindDevice skill.
    var findDevice = new FindDevice();
    findDevice.execute(event, context);
};

这是来自lambda的错误：

{
  "errorMessage": "Cannot read property 'PLAIN_TEXT' of undefined",
  "errorType": "TypeError",
  "stackTrace": [
    "getWelcomeResponse (/var/task/index.js:87:42)",
    "FindDevice.eventHandlers.onLaunch (/var/task/index.js:58:5)",
    "FindDevice.LaunchRequest (/var/task/AlexaSkill.js:10:37)",
    "FindDevice.AlexaSkill.execute (/var/task/AlexaSkill.js:91:24)",
    "exports.handler (/var/task/index.js:137:16)"
  ]
}

我知道这里有一个未定义的对象，但对于我来说，我找不出代码在哪里出错。我正在尝试从我的意图中取出插槽，然后根据所使用的插槽字将设备更改为ping。另外，因为我对此还很陌生，所以很多编码都是通过将东西拼凑在一起来完成的。我确实发现，当我删除所有的.PLAIN_TEXT代码行时，代码在lambda中运行，但随后在alexa技能测试区中断。我有一种预感，我不明白来自意图的插槽是如何传递的，但我在寻找我能理解的材料方面遇到了困难。任何帮助都是很棒的！

Answer 1

在determineDevice函数中，您将直接访问" device“插槽对象，而不是传入的实际值，因此它永远不会与您预定义的一组设备名称匹配。

slot对象有一个名称和一个值--当您在测试Alexa技能时，如果您在开发人员控制台的服务模拟器中查看Service Request JSON，您将看到类似以下内容：

{
"session": {
    "sessionId": "SessionId.dd05eb31-ae83-4058-b6d5-df55fbe51040",
    "application": {
    "applicationId": "amzn1.ask.skill.61dc6132-1727-4e56-b194-5996b626cb5a"
    },
    "attributes": {
    },
    "user": {
    "userId": "amzn1.ask.account.XXXXXXXXXXXX"
    },
    "new": false
},
"request": {
    "type": "IntentRequest",
    "requestId": "EdwRequestId.6f083909-a831-495f-9b55-75be9f37a9d7",
    "locale": "en-GB",
    "timestamp": "2017-07-23T22:14:45Z",
    "intent": {
    "name": "AnswerIntent",
    "slots": {
        "person": {
        "name": "person",
        "value": "Fred"
        }
    }
    }
},
"version": "1.0"
}

注意，在本例中，我有一个名为"person“的槽，但要获取槽中的值，您需要访问" value”属性。在您的示例中，您可以将determineDevice函数的第一行更改为：

var deviceSlot = intent.slots.Device.value;

顺便说一句，我发现Alexa-cookbook Github repository是学习如何使用Alexa SDK的重要资源，其中有大多数场景的示例。