async勉強会のやつ

without_async.js

const request = require('request');

const host = 'http://localhost:3000';


const getBook = () => {
  return new Promise((resolve, reject) => {
    request.get(`${host}/books/1`, (err, res, body) => {
      if (err) {
        reject(err)
      }
      resolve(JSON.parse(body));
    })
  });
};

const postBook = (params) => {
  return new Promise((resolve, reject) => {
    request.post({url: `${host}/books`, form: params}, (err, res, body) => {
      if (err) {
        reject(err)
      }
      resolve(JSON.parse(body));
    })
  });
};


let result1, result2, result3, result4;

getBook()
  .then(_data => {
    result1 = _data;
    result1.id = null;
    return postBook(result1)
  })
  .then(_data => {
    result2 = _data;
    return getBook()
  })
  .then(_data => {
    result3 = _data;
    result3.id = null;
    return postBook(result3)
  })
  .then(_data => {
    result4 = _data;
    console.log(result1);
    console.log(result2);
    console.log(result3);
    console.log(result4);
  })
  .catch(err => {
    console.log(err);
  });