node.js – Amazon AWS Lambda Alexa HTTP获取问题

我继续使用Amazon Lambda和alexa技能工具包获得以下代码的问题.我花了无数个小时在这上面,无法让它发挥作用.我一直收到这条消息,无法弄清楚为什么http get失败了. “请稍后再试”.它甚至不打印控制台消息.

var Alexa = require('alexa-sdk');
var http = require('http');
var APP_ID = "omitted";     
var SKILL_NAME = 'omitted';

var options = {
    host: 'api.forismatic.com',
    path: '/api/1.0/?method=getQuote&lang=en&format=text',
    method: 'GET'
};

exports.handler = function(event, context, callback) {
var alexa = Alexa.handler(event, context);
alexa.APP_ID = APP_ID;
alexa.registerHandlers(handlers);
alexa.execute();
};

var handlers = {
'LaunchRequest': function () {
    this.emit('Inspiration');
},
'IntentRequest': function() {
    this.emit('Inspiration');
},
'InspirationIntent': function () {
    this.emit('Inspiration');
},
'Inspiration': function () {
    var speechOutput = '';
    var text = '';
    http.get(options, function(res) {
        console.error("Got response: " + res.statusCode);
        res.on("data", function(chunk) {
        console.error("BODY: " + chunk);
        text = chunk;
    });
    }).on('error', function(e) {
        text = 'error' + e.message;
        console.error("Got error: " + e.message);
});
    if(text == ''){
    speechOutput = "Please try again later";
    }
    else{speechOutput = text;}
    this.emit(':tellWithCard', speechOutput, SKILL_NAME, text);
},
'AMAZON.HelpIntent': function () {
    var speechOutput = "You can ask Inspirational Quote for some advice.";
    var reprompt = "What would you like me to do?";
    this.emit(':ask', speechOutput, reprompt);
},
'AMAZON.CancelIntent': function () {
    this.emit(':tell', 'Goodbye!');
},
'AMAZON.StopIntent': function () {
    this.emit(':tell', 'Goodbye!');
},
'Unhandled': function() {
    this.emit('AMAZON.HelpIntent');
}
};

因为java脚本是异步的,所以这段代码：

if(text == ''){
speechOutput = "Please try again later";
}
else{speechOutput = text;}
this.emit(':tellWithCard', speechOutput, SKILL_NAME, text);

在调用API获得响应之前运行.

不幸的是,你不能只将上面的代码移到http.get块中,因为’this.emit’中的’this’将不再起作用,你将得到一个未定义的响应被发送回Alexa Skill.

我认为最好的解决方案是将http调用拉出到一个单独的函数中.调用该函数时,您必须使用回调来避免同一问题的lambda在转移到下一个代码行之前没有等待来自http调用的响应.因此,通过函数调用传递函数并从那里发送您的响应.注意 – 为此,你必须在函数调用之外为变量指定一个变量,并在函数调用中使用该变量而不是’this’.

示例如下：

var Alexa = require('alexa-sdk');
var http = require('http');
var APP_ID = "omitted";     
var SKILL_NAME = 'omitted';

var options = {
    host: 'api.forismatic.com',
    path: '/api/1.0/?method=getQuote&lang=en&format=text',
    method: 'GET'
};

exports.handler = function(event, context, callback) {
    var alexa = Alexa.handler(event, context);
    alexa.APP_ID = APP_ID;
    alexa.registerHandlers(handlers);
    alexa.execute();
};

var handlers = {
    'LaunchRequest': function () {
        this.emit('Inspiration');
    },
    'IntentRequest': function() {
        this.emit('Inspiration');
    },
    'InspirationIntent': function () {
        this.emit('Inspiration');
    },
    'Inspiration': function () {
        var speechOutput = '';
        var text = '';
        var self = this;
        getQuote(options, function (quote){
            if(quote == ''){
            speechOutput = "Please try again later";
            }
            else{speechOutput = quote;}
            self.emit(':tellWithCard', speechOutput, SKILL_NAME, text);
        }
    )},
    'AMAZON.HelpIntent': function () {
        var speechOutput = "You can ask Inspirational Quote for some advice.";
        var reprompt = "What would you like me to do?";
        res(this.emit(':ask', speechOutput, reprompt));
    },
    'AMAZON.CancelIntent': function () {
        this.emit(':tell', 'Goodbye!');
    },
    'AMAZON.StopIntent': function () {
        this.emit(':tell', 'Goodbye!');
    },
    'Unhandled': function() {
        this.emit('AMAZON.HelpIntent');
    }
};

function getQuote(options, callback){
    http.get(options, function(res) {
        console.error("Got response: " + res.statusCode);
        res.on("data", function(chunk) {
        console.error("BODY: " + chunk);
        text = '' + chunk;
        return callback(text);
    });
    }).on('error', function(e) {
        text = 'error' + e.message;
        console.error("Got error: " + e.message);
});
}