post-info.js

import fs from 'fs';
import fm from 'front-matter';
import markdown from 'markdown-it';
import hljs from 'highlight.js';
import chalk from 'chalk';
import { writeFile } from './utils';

//parse markdown to add highlight classes and reformat for line numbers
const md = new markdown({
  highlight: function (str) {
    //create line numbers for code block
    let lineNumber = 0;

    //pass in string to be highlighted
    const hl = hljs.highlightAuto(str, ['html', 'javascript', 'css', 'sass', 'shell']).value;

    const commentPattern = /<span class="hljs-comment">(.|\n)*?<\/span>/g;

    const adaptedHighlightedContent = hl.replace(commentPattern, data => {
      return data.replace(/\r?\n/g, () => {
        return '\n<span class="hljs-comment">';
      });
    });

    const contentBlock = adaptedHighlightedContent.split(/\r?\n/).map(lineContent => {
      return `<div class="code-line">
                <span class="code-line-number" data-pseudo-content=${++lineNumber}></span>
                <span class="code-line-content">${lineContent}</span>
              </div>`
    }).join('');

    return `<pre class="code"><code class="code-block">${contentBlock}</code></pre>`;
  }
});


  //get directory post
fs.readdir(`./src/post/article`, (err, posts) => {

  //if error in getting
  if (err) { throw err; }

  //create array to store list of post
  let postList = {};

  //create an array to store the tags which will make up our nav
  let nav = [];

  //map through each post and pull out the data
  posts.map(post => {
    const fileName = post;

    //get yaml front matter from each post file
    fs.readFile(`./src/post/article/${fileName}`, 'utf8', (err, data) => {

      //if error in getting
      if (err) { throw err; }

      //pull yaml front matter
      const content = fm(data);
      const postData = content.attributes;

      //parse markdown and store the html
      postData.body = md.render(content.body);

      //get file name and remove extension
      postData.filename = fileName.replace(/\.[^/.]+$/, "");

      //push new post object onto list array
      postList[fileName] = postData;

      //add post tags array to nav array to get filtered (no dupes)
      nav = nav.concat(postData.tags).reduce((a, b) => {
        if (a.indexOf(b) < 0 ) { a.push(b); }
        return a;
      },[]);

      //create json file with post data.
      writeFile(
        'tmp/data/post.json',
        JSON.stringify(postList, null, 2)
      );

      //create json file with post data.
      writeFile(
        'docs/static/data/post.json',
        JSON.stringify(postList, null, 2),
        chalk.red.bold(`SAVED TO POST.JSON: ${postData.filename}`)
      );
    });
  });
});