node.js HTTPs 调用返回未定义。亚马逊AWS

Question

我对 Node.js 完全陌生，但有以下代码，这些代码主要是通过剪切和粘贴编写的。它在 Amazon AWS 中运行，响应 Alexa 调用。我正在尝试阅读 thingspeak channel 来获取泳池的温度。该 URL 返回带有温度的 json。该 channel 由 esp8266 更新，该 esp8266 正在测量 pooltemp 并将其发布到 channel 。

不幸的是，我只得到了未定义的 pooltemp。我创建函数 getCall() 来从 thingspeak 获取温度。当我在 handlerinput 中使用变量 pooltemp 时，它是未定义的。其他一切工作正常。如果我在 handlerinput 中对 pooltemp 进行硬编码，我会得到我想要的响应。

它现在的工作方式如下:第一次运行 pooltemp 是未定义的。如果立即再运行一次，我会得到 pooltemp = 30(这是新的温度)。这至少表明对 thingspeak 的调用正在发挥作用。如果我在几分钟后再次运行它，它第一次又是未定义的。似乎 AWS 在函数完成后会保留该值一段时间。

/* eslint-disable  func-names */
/* eslint-disable  no-console */

const Alexa = require('ask-sdk');

var https = require('https');
var pooltemp;

  getCall();

//ThingSpeak Data Access

function getCall() {
  var options = {
    protocol: 'https:', 
    host: 'api.thingspeak.com',
    path: '/channels/494722/feeds.json?api_key=9HILOGJ9P2HRDPNO&results=1',
    method: 'GET'
  };

  var getReq = https.request(options, function(res) {
    console.log("\nstatus code: ", res.statusCode);
    var jsonData = '';
    res.on('data', function(data) {
        jsonData += data;
    });
    res.on('end', function() {
      console.log('We have all the data');
      var result = JSON.parse(jsonData);
      console.log('data: ', result);
      console.log('Pool temperature: ', result.feeds[0].field1);
      // Save the latest pool temperature.
      pooltemp = result.feeds[0].field1;
    });
  });

  //end the request
  getReq.end();
  getReq.on('error', function(err) {
    console.log("Error: ", err);
  });
}


const GetNewFactHandler = {
  canHandle(handlerInput) {
    const request = handlerInput.requestEnvelope.request;
    return request.type === 'LaunchRequest' ||
      (request.type === 'IntentRequest' &&
        request.intent.name === 'GetNewFactIntent');
  },
  
  
  
  handle(handlerInput) {

 
    //  var pooltemp = 22;
    var factIndex;
    const factArr = data;
    if (pooltemp <= 15) {
      factIndex = 0;
    }
    if (15 < pooltemp == pooltemp < 20) {
      factIndex = 1;
    }
    if (20 <= pooltemp == pooltemp < 25) {
      factIndex = 2;
    }
    if (pooltemp >= 25) {
      factIndex = 3;
    }
   
   
    const randomFact = factArr[factIndex];
    const speechOutput = 'Hold on a second, I will check for you.<break time="1s"/>Today it is ' + pooltemp + ' degrees in the pool. ' + randomFact;
    return handlerInput.responseBuilder
      .speak(speechOutput)
      .withSimpleCard(SKILL_NAME, randomFact)
      .getResponse();
    
  },
};

const HelpHandler = {
  canHandle(handlerInput) {
    const request = handlerInput.requestEnvelope.request;
    return request.type === 'IntentRequest' &&
      request.intent.name === 'AMAZON.HelpIntent';
  },
  handle(handlerInput) {
    return handlerInput.responseBuilder
      .speak(HELP_MESSAGE)
      .reprompt(HELP_REPROMPT)
      .getResponse();
  },
};

const ExitHandler = {
  canHandle(handlerInput) {
    const request = handlerInput.requestEnvelope.request;
    return request.type === 'IntentRequest' &&
      (request.intent.name === 'AMAZON.CancelIntent' ||
        request.intent.name === 'AMAZON.StopIntent');
  },
  handle(handlerInput) {
    return handlerInput.responseBuilder
      .speak(STOP_MESSAGE)
      .getResponse();
  },
};

const SessionEndedRequestHandler = {
  canHandle(handlerInput) {
    const request = handlerInput.requestEnvelope.request;
    return request.type === 'SessionEndedRequest';
  },
  handle(handlerInput) {
    console.log(`Session ended with reason: ${handlerInput.requestEnvelope.request.reason}`);

    return handlerInput.responseBuilder.getResponse();
  },
};

const ErrorHandler = {
  canHandle() {
    return true;
  },
  handle(handlerInput, error) {
    console.log(`Error handled: ${error.message}`);

    return handlerInput.responseBuilder
      .speak('Sorry, an error occurred.')
      .reprompt('Sorry, an error occurred.')
      .getResponse();
  },
};

const SKILL_NAME = 'Space Facts';
const GET_FACT_MESSAGE = 'Here\'s today temperature: ';
const HELP_MESSAGE = 'You can say tell me a space fact, or, you can say exit... What can I help you with?';
const HELP_REPROMPT = 'What can I help you with?';
const STOP_MESSAGE = 'Goodbye!';

const data = [
  'It is freezing cold. Swimming only for idiots',
  'It is not for wimps, but you may swim. Do you dare go for it?',
  'Which is a nice temperature for a Norwegian.',
  'This is quite comfortable and a swim should be really nice ',

];

const skillBuilder = Alexa.SkillBuilders.standard();

exports.handler = skillBuilder
  .addRequestHandlers(
    GetNewFactHandler,
    HelpHandler,
    ExitHandler,
    SessionEndedRequestHandler
  )
  .addErrorHandlers(ErrorHandler)
  .lambda();

Answer 1

我已经检查过这一点并对 getCall() 函数进行了一些修改，它现在应该可以工作了:

function getCall() {
  var options = {
    protocol: 'https:', 
    host: 'api.thingspeak.com',
    path: '/channels/494722/feeds.json?api_key=9HILOGJ9P2HRDPNO&results=1',
    method: 'GET'
  }

  var getReq = https.request(options, function(res) {
    console.log("\nstatus code: ", res.statusCode);
    var jsonData = '';
    res.on('data', function(data) {
        jsonData += data;
    });
    res.on('end', function() {
       console.log('We have all the data');
       var result = JSON.parse(jsonData);
       console.log('data: ', result);
       console.log('Pool temperature: ', result.feeds[0].field1);
       // Save the latest pool temperature.
       poolTemp = result.feeds[0].field1;
    });
  });

  //end the request
  getReq.end();
  getReq.on('error', function(err) {
    console.log("Error: ", err);
  });
}

getCall();

您也可以在脚本开头尝试此操作:

getCall();
setInterval(getCall, 10000);

这将每 10 秒刷新一次池温度。