了解 Alexa Skill 中的 HTTP 函数——JavaScript答案

【问题标题】：Understanding HTTP function inside Alexa Skill-- JavaScript了解 Alexa Skill 中的 HTTP 函数——JavaScript
【发布时间】：2020-05-19 20:00:45
【问题描述】：

我目前正在学习如何将我的 Amazon Lambda 函数（在 js 中）连接到 API。我发现以下代码有效，但我对 javascript 和 API 很陌生，并且不确定它在做什么。有人可以向我解释这个功能的作用以及它是如何工作的吗？谢谢！

function httpGet() {
  return new Promise(((resolve, reject) => {

    var options = {
      host: 'api.icndb.com',
      port: 443,
      path: '/jokes/random',
      method: 'GET',
    };

    const request = https.request(options, (response) => {
      response.setEncoding('utf8');
      let returnData = '';

      response.on('data', (chunk) => {
        returnData += chunk;
      });

      response.on('end', () => {
        resolve(JSON.parse(returnData));
      });

      response.on('error', (error) => {
        reject(error);
      });
    });
    request.end();
  }));
}

【问题讨论】：

标签： javascript api httprequest alexa alexa-skills-kit

【解决方案1】：

这里的response 对象是一个node.js stream，特别是一个“推送”流。（This 文章很好地解释了推/拉流）。

const request = https.request(options, (response) => {
  // Your request has been successfully made and you are 
  // handed a response object which is a stream, which will emit
  // a 'data' event when some data is available.
  response.setEncoding('utf8');
  let returnData = '';

  // A chunk of data has been pushed by the stream,
  // append it to the final response
  response.on('data', (chunk) => {
    returnData += chunk;
  });

  // All the data has been pushed by the stream.
  // 'returnData' has all the response data. Resolve the 
  // promise with the data.
  response.on('end', () => {
    resolve(JSON.parse(returnData));
  });

  // Stream has thrown an error.
  // Reject the promise
  response.on('error', (error) => {
    reject(error);
  });
});
request.end();

【讨论】：