feat(projects): Adds project thumbs and descriptions

lib/project.js

@@ -1,12 +1,16 @@
+const { Buffer } = require('buffer');
 const path = require('path');
 const fs = require('fs');
+const https = require('https');
 const marked = require('marked');
 const yaml = require('js-yaml');
+const { JSDOM } = require('jsdom');
+const sharp = require('sharp');
 const { getReadmeFileName } = require('./common');
 const pkg = require('../package.json');
 
 
-const { readFile } = fs.promises;
+const { stat, readFile, writeFile } = fs.promises;
 
 
 const getProjectTitle = ([token]) => {
@@ -130,6 +134,89 @@ const getLearningObjectives = async (dir, opts) => {
 };
 
 
+const getSummary = (tokens) => {
+  const headingIdx = tokens.findIndex(token => (
+    token.type === 'heading'
+    && token.depth === 2
+    && /(resumen|resumo)/i.test(token.text)
+  ));
+
+  if (headingIdx === -1 || tokens[headingIdx + 1].type !== 'paragraph') {
+    return null;
+  }
+
+  return marked.parse(tokens[headingIdx + 1].text);
+};
+
+
+const fetchImage = src => new Promise((resolve, reject) => {
+  https.get(src, (resp) => {
+    if (resp.statusCode !== 200) {
+      return reject(new Error(`HTTP error ${resp.statusCode}`));
+    }
+
+    let buffer;
+    resp.on('error', reject);
+    resp.on('data', (chunk) => {
+      buffer = (typeof buffer === 'undefined')
+        ? chunk
+        : Buffer.concat([buffer, chunk]);
+    });
+    return resp.on('end', () => resolve(buffer));
+  });
+});
+
+
+const getCoverImage = (tokens) => {
+  const firstTokenWithImg = tokens.find(token => (
+    token.type === 'paragraph'
+    && (
+      /!\[.+\]\(.+\)/g.test(token.text)
+      || /<img /g.test(token.text)
+    )
+  ));
+
+  if (!firstTokenWithImg) {
+    return null;
+  }
+
+  const html = marked.parse(firstTokenWithImg.text);
+  const { window } = new JSDOM(html);
+  return window.document.querySelector('img').src;
+};
+
+
+const getImages = (dir, tokens) => {
+  const cover = getCoverImage(tokens);
+  const thumbFile = path.join(dir, 'thumb.png');
+
+  const createThumb = async (src) => {
+    const buffer = await fetchImage(src);
+    const data = await sharp(buffer).resize(395).toBuffer();
+    await writeFile(thumbFile, data, { encoding: 'base64' });
+    return data;
+  };
+
+  return stat(thumbFile)
+    .then(() => readFile(thumbFile, 'base64'))
+    .catch((err) => {
+      if (err.code !== 'ENOENT') {
+        throw err;
+      }
+      // does not exist!
+      return !cover ? null : createThumb(cover);
+    })
+    .then(data => ({
+      cover,
+      thumb: (
+        data
+          ? `data:image/png;base64,${data.toString('base64')}`
+          : null
+      ),
+    }));
+};
+
+
 module.exports = (dir, { Project }, opts = {}) => {
   const readme = path.join(dir, getReadmeFileName(opts.locale));
   const basename = path.basename(dir);
@@ -170,7 +257,9 @@ module.exports = (dir, { Project }, opts = {}) => {
       title: getProjectTitle(tokens),
       locale: opts.locale,
       track: opts.track,
+      summary: getSummary(tokens),
       learningObjectives: await getLearningObjectives(dir, opts),
+      ...(await getImages(dir, tokens)),
     }))
     .then((json) => {
       const project = new Project(json);