index.js

'use strict';
const http = require('http');

/*
* HTTP Cloud Function.
*
* @param {Object} req Cloud Function request context.
* @param {Object} res Cloud Function response context.
*/
exports.poetryDesk = function poetryDesk (req, res) {
  console.log('poetryDesk start request: ', req)
  let poet = '';
  if (req.body.result.parameters['poet']) {
    poet = req.body.result.parameters['poet'];
  }
  console.log('poetryDesk poet: ', poet)
  // Call the poetry API
  getRandomPoemByPoet(poet)
    .then(output => {
      console.log('poetryDesk getRandomPoemByPoet fulfillment output: ', output)
      console.log('poetryDesk res: ', res)
      // Return the results of the poetry API to Dialogflow
      res.setHeader('Content-Type', 'application/json');
      res.send(JSON.stringify({ speech: output, displayText: output }));
    }, rejectReason => {
      console.log('poetryDesk getRandomPoemByPoet rejectReason: ', rejectReason)
      console.log('poetryDesk res: ', res)
      res.setHeader('Content-Type', 'application/json');
      res.send(JSON.stringify({ speech: 'Something went wrong, check the logs', displayText: rejectReason }));
    })
    .catch(error => {
      console.log('poetryDesk error: ', error)
      // If there is an error let the user know
      res.setHeader('Content-Type', 'application/json');
      res.send(JSON.stringify({ speech: error, displayText: error }));
    });
};

/*
* getRandomPoemByPoet
*
* @param {String} poet Poet name to search in poetrydb api, first then middle (if applicable) then last name, separated by spaces, requires exact match
*/
const getRandomPoemByPoet = poet => {
  return new Promise((resolve, reject) => {
    let speechOutput = '';

    // neither encodeURI nor encodeURIComponent work here since GC converts spaces to %C2%A0, but the api only supports %20 or + for spaces
    const poemTitlePath =
      'http://poetrydb.org/author/' + poet.replace(/\s+/, '+') + '/title';
    console.log('getRandomPoemByPoet API call: ', poemTitlePath)
    http.get(poemTitlePath, res => {
      // Handle server errors
      const { statusCode } = res;
      let error;
      if (statusCode !== 200) {
        error = new Error(`Request Failed - Status Code: ${statusCode}`);
        console.error(error.message);
        res.resume(); // consume response data to free up memory
        speechOutput = `I'm sorry, there was an error with the poetry service - we've been notified, please try again later`;
        resolve(speechOutput);
      }

      // Handle server response
      let body = ''; // store the response chunks
      res.on('data', d => {
        body += d;
      }); // accumulate response chunks
      res.on('end', () => {
        let poems = JSON.parse(body);
        console.log('getRandomPoemByPoet http end poems: ', poems)
        if (poems.length > 0) {
          const randomPoemTitle =
            poems[Math.floor(Math.random() * poems.length)].title;
          getPoemByTitle(randomPoemTitle).then(speechOutputData => {
            if (speechOutputData.poemFound !== false) {
              speechOutput = `This ${speechOutputData.poemLines}-line poem by ${
                speechOutputData.poemAuthor
              } is called ${speechOutputData.poemTitle}: ${
                speechOutputData.poemBody
              }`;
              console.log('getRandomPoemByPoet resolve speechOutput: ', speechOutput)
              resolve(speechOutput);
            } else {
              // todo: try a different poem from the list
            }
          });
        } else {
          // todo: log the request
          speechOutput = `Sorry, I don't currently have any poems by ${poet}, but we'll make a note to check them out. Please try again later!`;
          console.log('getRandomPoemByPoet resolve speechOutput: ', speechOutput)
          resolve(speechOutput);
        }
      });

      // Handle client errors
      res.on('error', error => {
        console.log('getRandomPoemByPoet http error, rejecting: ', error)
        reject(error); // todo: do we want to resolve here instead?
      });
    });
  });
};

/*
* getPoemByTitle
*
* @param {String} poemTitle Poem title to search in poetrydb api, does not require exact match
*/
const getPoemByTitle = poemTitle => {
  return new Promise((resolve, reject) => {
    let poemFound = false;
    let poemAuthor = '';
    let poemBody = '';
    let poemLines = '';
    const poemLinesPath =
      'http://poetrydb.org/title/' + poemTitle.replace(/\s+/, '+');
    http.get(poemLinesPath, res => {
      let poemData = '';
      res.on('data', d => {
        poemData += d;
      });
      res.on('end', () => {
        console.log('poemData: ', poemData)
        const poemObj = JSON.parse(poemData);
        if (poemObj.length > 0 && poemData) {
          poemTitle = poemObj[0].title;
          poemAuthor = poemObj[0].author;
          poemBody = poemObj[0].lines.join();
          poemLines = poemObj[0].linecount.toString();
          poemFound = true;
        }
        const speechOutputData = {
          poemFound: poemFound,
          poemTitle: poemTitle,
          poemAuthor: poemAuthor,
          poemLines: poemLines,
          poemBody: poemBody,
        };
        console.log('getPoemByTitle resolve speechOutputData: ', speechOutputData)
        resolve(speechOutputData);
      });
      res.on('error', error => {
        reject(error);
      });
    });
  });
};