3-function.js

'use strict';

const RENDERERS = {
  abstract: () => {
    console.log('Not implemented');
  },

  console: (data) => {
    console.table(data);
  },

  web: (data) => {
    const keys = Object.keys(data[0]);
    const line = (row) =>
      '<tr>' + keys.map((key) => `<td>${row[key]}</td>`).join('') + '</tr>';
    const output = [
      '<table><tr>',
      keys.map((key) => `<th>${key}</th>`).join(''),
      '</tr>',
      data.map(line).join(''),
      '</table>',
    ];
    console.log(output.join(''));
  },

  markdown: (data) => {
    const keys = Object.keys(data[0]);
    const line = (row) =>
      '|' + keys.map((key) => `${row[key]}`).join('|') + '|\n';
    const output = [
      '|',
      keys.map((key) => `${key}`).join('|'),
      '|\n',
      '|',
      keys.map(() => '---').join('|'),
      '|\n',
      data.map(line).join(''),
    ];
    console.log(output.join(''));
  },
};

const context = (rendererName) => {
  const renderer = RENDERERS[rendererName] || RENDERERS.abstract;
  return (data) => renderer(data);
};

// Usage

const png = context('png');
const con = context('console');
const web = context('web');
const mkd = context('markdown');

const persons = [
  { name: 'Marcus Aurelius', city: 'Rome', born: 121 },
  { name: 'Victor Glushkov', city: 'Rostov on Don', born: 1923 },
  { name: 'Ibn Arabi', city: 'Murcia', born: 1165 },
  { name: 'Mao Zedong', city: 'Shaoshan', born: 1893 },
  { name: 'Rene Descartes', city: 'La Haye en Touraine', born: 1596 },
];

console.group('Unknown Strategy:');
png(persons);
console.groupEnd();

console.group('\nConsoleRenderer:');
con(persons);
console.groupEnd();

console.group('\nWebRenderer:');
web(persons);
console.groupEnd();

console.group('\nMarkdownRenderer:');
mkd(persons);
console.groupEnd();